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HomeMy WebLinkAbout01-18-2018 Hearing Examiner Agenda Packet HEARING EXAMINER January 18, 2018 5:30 p.m. City Council Chambers 25 West Main Street I. Case No: PLT17-0001 / VAR17-0002 – North Ridgeview Estates Applicant(s) Property Owner: Jeff Potter, Auburn Ridgeview, LLC Request: Preliminary Plat - subdivide approximately 30 acres into 30 single-family residential lots on a site Zoned R-1, Residential Zone, One Dwelling Unit Per Acre. Project Location: East side of 124th Ave. SE, approximately 600 ft. South of SE 282nd St. Parcel Number(s): 332205-9103, 332205-9115, 332205-9154 AGENDA BILL APPROVAL FORM Agenda Subject: PLT17-0001, VAR17-0002, DEV17-0003, Preliminary Plat of North Ridgeview Estates and Variance to Development Standards (setbacks) Date: January 8, 2018 Department: Community Development & Public Works, Planning Services Division Attachments: (See exhibit listing at the end of this report) Budget Impact: N/A Administrative Recommendation: Hearing Examiner to conduct a public hearing and approve the requested preliminary plat and variance, with conditions. Background Information: APPLICANT: Jeff Potter PROPERTY OWNER: Jeff Potter Auburn Ridgeview, LLC Auburn Ridgeview, LLC 27203 216th Ave, SE #5 27203 216th Ave, SE #5 Maple Valley, WA 98038 Maple Valley, WA 98038 REQUEST: File Nos. PLT17-0001, VAR17-0002, DEV17-0003: Preliminary plat application to subdivide 29.7 acres into 30 single -family residential lots. The site is zoned R-1, Residential, which allows 1 lot per acre. The site is also located within the “Urban Separator Overlay”, which requires 50% of the site to be set aside as open space, and the lots to be clustered and maintain at least 8,000 sq. ft. of lot area; the proposed lots range in size from 10,115 sq. ft. to 21,490 sq. ft. with an average lot size of 13,235 sq. ft. A variance to the zoning development standards for setbacks has also been requested to be lessened to coincide with the proposed lot sizes, rather than the standard setbacks of the R-1, Residential zoning district. A plat modification has also been requested from the clustering requirements of the “Urban Separator Overlay”. Four Deviation requests have also been requested relating to engineering standards. LOCATION: East side of 124th Ave. SE, approximately 600 ft. south of SE 282nd St., King Co. Parcel Nos. 332205-9103, 332205-9115, and 332205-9154. Reviewed by Council & Committees: Arts Commission COUNCIL COMMITTEES: Airport Finance Hearing Examiner Municipal Serv. Human Services Planning & CD Park Board Public Works Planning Comm. Other Reviewed by Departments & Divisions: Building M&O Cemetery Mayor Finance Parks Fire Planning Legal Police Public Works Human Resources Information Services Action: Committee Approval: Yes No Council Approval: Yes No Call for Public Hearing ___/___/____ Referred to Until ___/___/____ Tabled Until _ _/___/__ _ Councilmember: Staff: Gouk Meeting Date: January 18, 2018 Item Number: North Ridgeview Estates Plat Hearing Examiner Packet Page 1 of 422 Agenda Subject: PLT17-0001, VAR17-0002, DEV17-0003, Preliminary Plat of North Ridgeview Estates and Variance to Development Standards (setbacks) Date: January 8, 2018 Page 2 of 29 Summary of Staff Recommendations: Preliminary Plat Staff recommends the preliminary plat be approved, with conditions. Plat Modification Staff recommends the plat modification request to clustering lots in groups of 8 be approved, with no conditions. Variance Staff recommends the Variance request for reduced setbacks be approved, with no conditions. Deviation Requests The City Engineer recommends conditional approval of the four Deviation requests. North Ridgeview Estates Plat Hearing Examiner Packet Page 2 of 422 Agenda Subject: PLT17-0001, VAR17-0002, DEV17-0003, Preliminary Plat of North Ridgeview Estates and Variance to Development Standards (setbacks) Date: January 8, 2018 Page 3 of 29 Subject Property and Adjacent Property Comprehensive Plan Designation, Zoning Classification and Current Land Use: Comprehensive Plan Designation Zoning Classification Current Land Use Project Site Single Family with Urban Separator Overlay R-1 Residential Zone – One Dwelling Unit per Acre with Urban Separator Overlay Vacant North Single Family with Urban Separator Overlay R-1 / Urban Separator Single-Family Residences / Vacant South Single Family and Institutional with Urban Separator Overlay R-1 and P-1 Public Use / Urban Separator Single-Family Residences / Auburn Mountain View High School East Single Family with Urban Separator Overlay R-1 / Urban Separator Single-Family Residences / Vacant West Single Family with Urban Separator Overlay R-1 / Urban Separator 124th Ave. SE / Single-Family Residences Excerpted Zoning Map: North Ridgeview Estates Plat Hearing Examiner Packet Page 3 of 422 Agenda Subject: PLT17-0001, VAR17-0002, DEV17-0003, Preliminary Plat of North Ridgeview Estates and Variance to Development Standards (setbacks) Date: January 8, 2018 Page 4 of 29 Excerpted Comp Plan Map: Aerial Vicinity Map: North Ridgeview Estates Plat Hearing Examiner Packet Page 4 of 422 Agenda Subject: PLT17-0001, VAR17-0002, DEV17-0003, Preliminary Plat of North Ridgeview Estates and Variance to Development Standards (setbacks) Date: January 8, 2018 Page 5 of 29 I. SEPA STATUS: A Determination of Non-Significance (DNS) was issued under City File No. SEP17-0001 on December 7, 2017, see Exhibit 4. The comment period ended December 22, 2017 and the appeal period ended January 5, 2018. Three written comments were received, see Exhibit 5. No appeal of the SEPA decision was received. II. FINDINGS OF FACT: General Background and Information 1. Jeff Potter, of Auburn Ridgeview, LLC, property owner and Applicant (“Applicant”), submitted a Preliminary Plat application, a Variance application, and an associated SEPA application on January 12, 2017 to subdivide approximately 29.7 acres (“Site”) into 30 single-family residential lots (“Project”). 2. The Site is located on the east side of 124th Ave. SE, approximately 600 ft. south of SE 282nd St. and southeast of the 3-way intersection of 124th Ave. SE and SE 284th St, see Vicinity Map, above. The Site is located within the City of Auburn’s corporate limits, and referenced by King County Tax Assessor Parcel Nos. (APN) 332205-9103, 332205-9115, and 332205-9154. 3. The Site is currently vacant, less the two unused barns that are on the Site. 4. The Site has a squared-geometric shape, as shown and dimensioned here: 5. The Site will take access from 124th Ave. SE, a Minor Arterial, which borders the west side. The plat will construct a full new roadway (“Road A”) through the Site to the southeast corner of the site, situating Road A for future extension to 132nd Ave. SE. Lots 1 through 11 and 20 through 23 will take direct access off of Road A, a new “Residential Collector” classification street; Lots 12 through 19 will take access from a cul-de-sac (“Road B”) a “Local Residential” street, with Lots 14 and 15 using a shared driveway proposed as a private tract (“Tract L”); and, Lots 24 through 30 will take access from another cul-de-sac (“Road C”), a “Local Residential” street. N North Ridgeview Estates Plat Hearing Examiner Packet Page 5 of 422 Agenda Subject: PLT17-0001, VAR17-0002, DEV17-0003, Preliminary Plat of North Ridgeview Estates and Variance to Development Standards (setbacks) Date: January 8, 2018 Page 6 of 29 6. The Site is zoned R-1 Residential which has a minimum and maximum (base) density of one (1) unit per acre; the site is approximately 29.7 acres, which for density calculations is rounded up to 30 lots. The Comprehensive Plan Land Use Designation of the Site is “Single Family”. The Site is also located within the boundaries of the “Urban Separator Overlay”. 7. There are 3 Category III wetlands, ranging in size from approximately 1,000 sq. ft. up to approximately 1 acre are located on the Site and will be placed in 3 separate tracts on the final plat map. These tracts will also include the applicable 25-ft. minimum wetland buffer to the on-site wetlands. A draft Critical Area Mitigation Plan (enhancement plan) for the wetlands and wetland buffers is shown on Exhibit 12. By City critical area regulations, the enhancement of the wetlands, themselves, is not required, but is shown on the plans. The Applicant is required by City regulations to enhance the buffers. The Applicant is aware that enhancement of the wetland in addition to the buffer will be beneficial environmentally and likely reduce the amount of maintenance and monitoring that is required. A final enhancement plan will be reviewed with the future submittal of the Public Facility Extension (FAC) (civil) plans for the Project. 8. The Site is located within Groundwater Protection Zone 4, the least stringent classification and requires implementation of best management practices (BMPs) for water resource protection per ACC 16.10.120(E)(2). 9. The Site is not located within any shoreline designation. 10. The Site is not located in the regulatory floodplain per Federal Emergency Management Agency (FEMA) maps. 11. No state or federal candidate threatened or endangered plant or animal species or habitat has been identified on the Site. 12. The Site is located within the boundaries of, and will be served by, King Count y Water District No. 111 for public water. 13. The Site is located within the boundaries of, and will be served by, Soos Creek Sewer and Water District for public sewer. 14. A combined Notice of Application, Notice of Public Hearing, and Determination of Non-significance, was issued on December 7, 2017 (Exhibit 4). The notices were posted at the Site, mailed to adjacent property owners within 300 ft. of the Site, and published in The Seattle Times newspaper. The City received three comment letters on the project (Exhibit 5). One letter from the Muckleshoot Indian Fisheries division reported on the status of on-site critical areas; one from a neighbor to the north with concerns about the amount of water in the stream/wetland areas; and, one comment regarding the provision of sidewalks on 124th Ave. SE. The City did respond to these comment letters; although the Muckleshoot comment has been addressed in this Staff Report (stormwater quality entering the stream to the north). Preliminary Plat Findings 1. As stated in ‘Findings of Fact’ No. 6, above, the Site is located in the R-1, Residential zoning district and also within the “Urban Separator Overlay”. The Urban Separator Overlay was adopted by the City from King County when the City annexed Lea Hill in 2008 that has its origin in King County countywide planning policies. Properties within the Urban Separator Overlay are required to lower intensity of development by utilizing both lot averaging and clustering when subdividing. The lot averaging requirement is taken from ACC 18.21.030 (emphasis added): North Ridgeview Estates Plat Hearing Examiner Packet Page 6 of 422 Agenda Subject: PLT17-0001, VAR17-0002, DEV17-0003, Preliminary Plat of North Ridgeview Estates and Variance to Development Standards (setbacks) Date: January 8, 2018 Page 7 of 29 “18.21.030 Urban separator overlay. A. Purpose. The purpose of this section is to provide for additional development standards to address the area designated as urban separator in the city’s comprehensive plan, as prescribed in the interlocal agreement between the city and King County approved under city of Auburn Resolution No. 4113 and identified on the city of Auburn comprehensive land use map. Unless otherwise provided for in this section, all other provisions and requirements of this title shall apply to properties within the urban separator overlay. B. Development Standards. For property located within a designated urban separator, lot averaging shall be required. The regulations of ACC 18.21.010(F) shall apply in situations where lot averaging is used. C. All marijuana related businesses and marijuana cooperatives are prohibited land uses within the urban separator overlay.“ 2. The regulations for lot averaging can be found in ACC 18.21.010(F). The regulations are as follows (in italics) followed by Staff’s analysis: “F. Lot Averaging – R-1 Zone. It may be possible to subdivide land in the R-1 zone into lots smaller than 35,000 square feet if the property has a significant amount of nonbuildable land due to steep slopes, wetlands or similar features that would be in the public’s best interest to maintain. The following regulations shall apply in situations where lot averaging is permitted or required: Staff Analysis: The Project is required to provide 14.85 acres as Open Space; 15.33 acres are proposed (51.6%). The following nine (9) Open Space tracts are proposed:  Tract A – Located along the western boundary of the Project, westerly of the Tract E ‘Drainage Facility’. This Tract contains “Wetland A”, the wetland buffer, and some existing native vegetation (grasses and some trees).  Tract B – This small tract is located to the east of Tract E. This tract contains “Wetland B” and the wetland buffer.  Tract C – Located along the northern property line, in the northwest portion of the Site. This tract contains “Wetland C” and the wetland buffer.  Tract D – This large tract composes the remainder of the open space north and east of Road A. This tract is mainly existing native vegetation (grasses and a few trees) and will also include a 12-ft. gravel City sewer maintenance road that will double as a pedestrian trail as well as stormwater low impact development (LID) facilities for the future residences (e.g. dry wells, dispersion trenches).  Tract F – Located south of Road A. this tract contains existing native vegetation (grass and trees) and a barn that will be demolished. Extensive grading along the north portion of this tract will be done in order to construct Road A.  Tract H – Located west of Road A, between Road A and the City of Kent water reservoir tank (Parcel No. 332205-9177). This tract contains existing native vegetation (grasses and trees) as well as a stormwater LID facility for Lot 30.  Tract I – Located between the rear of Lot 28 and the City of Kent water reservoir tank. This tract is encumbered by an existing landscape easement that was put in place for the City of Kent water tank; however, it does not appear th at the landscape easement was ever utilized as the water tank was relocated to the interior of Parcel 332205-9177. A stormwater LID facility for Lot 28 is proposed to be used on this Tract and there will be access to the Tract from Road C for maintenance.  Tract J – This small tract is located south of Road A and east of Lot 24. There is some existing vegetation. North Ridgeview Estates Plat Hearing Examiner Packet Page 7 of 422 Agenda Subject: PLT17-0001, VAR17-0002, DEV17-0003, Preliminary Plat of North Ridgeview Estates and Variance to Development Standards (setbacks) Date: January 8, 2018 Page 8 of 29 Tract K – This small tract is located east of Road A and south of Road B. There is some existing native vegetation. There are no applicable Auburn City Code (ACC) sections that apply to this project that provide a specific definition of open space, however, ACC 17.26.030(D)(8) does provide some guidance on open space elements. Any areas within the proposed open space tracts that are disturbed during construction of the plat, or the single-family residences, will be required to be restored to a similar or more enhanced state. “2. The number of allowable lots in a subdivision shall be determined by multiplying the total number of acres in the subdivision by one. Any fraction shall be rounded to the nearest whole number with one-half being rounded up.” Staff Analysis: The Site is approximately 29.7 acres in size which, rounded, up equals 30 lots. “3. The minimum size of any lot shall be 8,000 square feet. For lots less than 35,000 square feet, the minimum lot width shall be consistent with the requirements of the R -5 zone (Chapter 18.07 ACC). All other applicable development standards related to the R-1 zone will continue to apply.” Staff Analysis: The average lot size is 13,235 sq. ft. with the smallest proposed lot at 10,115 sq. ft. and the largest lot at 21,490 sq. ft. The required lot width of the R-5 zone is 50 ft.; all lots are able to meet this requirement (lot width is defined as measuring at a midpoint between the front and rear lot lines (ACC 18.04.560(B), definition of “lot width”)). The Applicant has requested a Variance from the required zoning setback development standards of the R-1 zone, to use setback standards of the R-5 zoning district that are more appropriate to implementation of clustering provisions. “4. Lots within the subdivision shall be clustered so as to provide for continuity of open space within the subdivision and, where possible, with adjoining parcels.” Staff Analysis: The Applicant has requested a Plat Modification (allowed per Chapter 17.18 ACC) to this requirement. For further analysis see ‘Plat Modification Findings’ and ‘Plat Modification Conclusions’, below. “5. Each lot within a subdivision shall illustrate a building area within which the house, accessory structures, and parking areas shall be constructed. The building area shall be exclusive of setbacks, nonbuildable areas or any required buffers from the nonbuildable areas. Any preliminary plat, final plat or short plat shall illustrate the building area for each lot. Any future construction will be limited to the identified building area.” Staff Analysis: Buildable areas for the future single-family residences and driveways/parking areas have been shown on the Preliminary Plat maps, reference Sheets 4-5 on Exhibit 6. “6. A native growth protection easement or similar device, which may include provisions for the limited removal of vegetation and passive use of the easement, that perpetually protects the nonbuildable areas must be recorded with the final plat or short plat.” Staff Analysis: All open space (including wetlands and wetland buffers) will be located within tracts upon recording of the final plat; to be owned and maintained by the Homeowner’s North Ridgeview Estates Plat Hearing Examiner Packet Page 8 of 422 Agenda Subject: PLT17-0001, VAR17-0002, DEV17-0003, Preliminary Plat of North Ridgeview Estates and Variance to Development Standards (setbacks) Date: January 8, 2018 Page 9 of 29 Association (“HOA”). The City will require growth protection easement or other appropriate restrictions to ensure preservation of open space. 3. Per ACC 17.26.020 and ACC 17.26.030(A), proposed subdivisions zoned R-1, and located wholly or partially within the Urban Separator Overlay, are subject to the ‘Cluster Subdivision’ requirements of Chapter 17.26 ACC. The requirements are as follows (in italics) followed by Staff’s analysis: “A. All subdivisions and short subdivisions in the R-1 zoning district shall be required to be clustered pursuant to this section when the property is located wholly or partially within an urban separator as designated on the city of Auburn comprehensive land use plan map. B. Cluster subdivisions and short subdivisions shall be subject to the development standards outlined in Chapter 18.07 ACC, as modified by Chapter 18.21 ACC. These standards include, but are not limited to, minimum lot size, width, yards, setbacks, parking, landscaping, signage, etc. C. Applicants for cluster subdivisions shall demonstrate compliance to all applicable design standards and construction standards for the city of Auburn.” Staff Analysis: As the Site is located wholly within the Urban Separator Overlay, the proposed preliminary plat has been designed to meet the requirements of cluster subdivisions. The development standards have been analyzed in ‘Findings of Fact’ No. 2, above. Except as discussed in the ‘Deviation Findings’ and ‘Deviation Conclusions’, below, the proposed subdivision will meet applicable engineering design and construction standards. “D. The provisions of this title, as well as other applicable portions of the Auburn City Code, shall apply unless specifically exempted. In addition, the following standards shall apply to clustered subdivisions or short subdivisions: 1. Location. The cluster residential development shall be required in the R-1 zoning district within urban separator areas.” Staff Analysis: The Site is located in the R-1 zone and located within the Urban Separator Overlay. “2. Permitted Uses. Permitted uses in cluster residential developments shall be consistent with Chapter 18.07 ACC, as modified by Chapter 18.21 ACC. In no case shall zero lot line development be permitted in a cluster subdivision.” Staff Analysis: Single-family residences are proposed for the lots being created, which are a Permitted use. Any other/future uses would be subject to the use regulations in effect at that time (e.g. home occupations). “3. Minimum Area. No minimum area is established for a cluster residential development.” Staff Analysis: The Project is approximately 29.7 acres in size. “4. Permitted Density. The maximum number of dwelling units permitted in a cluster development shall be no greater than the number of dwelling units allowed pursuant to Chapter 18.07 ACC, as modified by Chapter 18.21 ACC.” Staff Analysis: As stated in ‘Findings of Fact’ No. 2, above, the Site is approximately 29.7 acres in size which, which when rounded, up as allowed by the density standards, equals 30 lots. North Ridgeview Estates Plat Hearing Examiner Packet Page 9 of 422 Agenda Subject: PLT17-0001, VAR17-0002, DEV17-0003, Preliminary Plat of North Ridgeview Estates and Variance to Development Standards (setbacks) Date: January 8, 2018 Page 10 of 29 “5. Lot Size. The lot area of individual building lots within a cluster subdivision or short subdivision shall be no less than that provided for in Chapter 18.07 ACC, as modified by Chapter 18.21 ACC. New lots created by any subdivision or short subdivision action shall be clustered in groups not exceeding eight units. There may be more than one cluster per project. Separation between cluster groups shall be a minimum of 120 feet.” Staff Analysis: The Applicant has requested a Plat Modification (allowed per Chapter 17.18 ACC) to this cluster requirement. For further analysis see ‘Plat Modification’, below. “6. Lot Width. The lot width for individual building lots in a cluster subdivision or short subdivision shall be no less than that provided for in Chapter 18.07 ACC, as modified by Chapter 18.21 ACC.” Staff Analysis: As stated in ‘Findings of Fact’ No. 2, above, all of the proposed lots within the subdivision are able to meet the 50-ft. lot width requirement. “7. Other Development Standards. Development standards other than lot size and lot w idth shall be the same as are required by Chapter 18.07 ACC, as modified by Chapter 18.21 ACC.” Staff Analysis: As stated in ‘Findings of Fact’ No. 2, above, the Applicant has requested a Variance from the required setbacks of the R-1 zone, to instead use the required setbacks applicable to the R-5 zone. “8. Common Open Space. a. Amount Required. The common open space in a cluster subdivision or short subdivision shall be a minimum of 50 percent of the parcel, and may include cr itical areas and their buffers.” Staff Analysis: As stated in ‘Findings of Fact’ No. 2, above, the Project proposes 51.6%, or 15.33 acres, of open space within the subdivision. Note that in this instance the word “parcel” as used in this criterion is being used interchangeably to refer to the set of multiple parcels that comprise the Site. “b. Nonconstrained Areas Defined. For purposes of this section, the nonconstrained area of the parcel is defined as all areas of the parcel, minus critical areas, as defined in Chapter 16.10 ACC as currently and hereinafter amended, and buffers. c. Buildable Area. After accounting for the 50 percent open space requirement, the remainder of the nonconstrained area of the parcel shall be the buildable area of the parcel. d. Layout of Common Open Space. The common open space tracts created by clustering shall be located and configured in the manner that best connects and increases protective buffers for environmentally sensitive areas, connects and protects area wildlife habitat, creates connectivity between the open space provided by the clustering and other adjacent open spaces as well as existing or planned public parks and trails, and maintains scenic vistas.” Staff Analysis: The largest expanse of open space is located in the northern portion of the Site; this area is also where the critical areas (wetlands) and their associated buffers are located, as well as the stormwater facility (pond). This area of the Site will also continue the connectivity with the properties to the north, which contains Soosette Creek, a known fish- North Ridgeview Estates Plat Hearing Examiner Packet Page 10 of 422 Agenda Subject: PLT17-0001, VAR17-0002, DEV17-0003, Preliminary Plat of North Ridgeview Estates and Variance to Development Standards (setbacks) Date: January 8, 2018 Page 11 of 29 bearing stream, is located. The other open space tracts have been distributed throughout the Project to help provide a spacious feel to the subdivision. “e. Future Development Prohibited. Future development of the common open space shall be prohibited. Except as specified on recorded documents creating the common open space, all common open space resulting from lot clustering shall not be altered or disturbed in a manner that degrades adjacent environmentally sensitive areas, rural areas, agricultural areas, or resource lands; impairs scenic vistas and the connectivity between the open space provided by the clustered development and adjacent open spaces; degrades w ildlife habitat; or impairs the recreational benefits enjoyed by the residents of the development.” Staff Analysis: All open space tracts will be required by the City to be permanently protected from development by indicating as such through restrictions on the final plat map and contained within the CC&R’s. This requirement is proposed as a condition. f. Conveyance of Common Open Space. Such common open spaces shall be conveyed to residents of the development, conveyed to a homeowners’ association for the benefit of the residents of the development, or conveyed to the city with the city’s consent and approval. Staff Analysis: The open space tracts will be owned and maintained by the future Homeowner’s Association. Plat Modification Findings 1. The Applicant has requested a plat modification from the following Code section regarding clustering of the lots within the Project: “ACC 17.26.030(D) 5. Lot Size. The lot area of individual building lots within a cluster subdivision or short subdivision shall be no less than that provided for in Chapter 18.07 ACC, as modified by Chapter 18.21 ACC. New lots created by any subdivision or short subdivision action shall be clustered in groups not exceeding eight units. There may be more than one cluster per project. Separation between cluster groups shall be a minimum of 120 feet.” The Applicant has prepared a written statement addressing this plat modification, see Exhibit 13. 2. Per ACC 17.18 ‘Modifications for Formal Subdivisions’, the Hearing Examiner may approve a modification of any standard or specification established or referenced by ACC 17.14 ‘Improvement Requirements – Subdivisions’. ACC 17.14.090 then lists the requirements for lots (i.e. size, shape, etc.) and references the cluster subdivision regulations of Chapter 17.26 ACC and the lot size requirements of ACC Title 18 ‘Zoning’; the Hearing Examiner therefore may approve a plat modification request for the clustering requirements upon making the findings of fact listed in ACC 17.18.030. See ‘Plat Modifications’ under ‘Conclusions’, below. North Ridgeview Estates Plat Hearing Examiner Packet Page 11 of 422 Agenda Subject: PLT17-0001, VAR17-0002, DEV17-0003, Preliminary Plat of North Ridgeview Estates and Variance to Development Standards (setbacks) Date: January 8, 2018 Page 12 of 29 Variance Findings 1. The Applicant has requested a Variance for setbacks from the following Code section regarding setbacks within the Project: “ACC 18.21.010(F) 3. The minimum size of any lot shall be 8,000 square feet. For lots less than 35,000 squ are feet, the minimum lot width shall be consistent with the requirements of the R -5 zone (Chapter 18.07 ACC). All other applicable development standards relat ed to the R-1 zone will continue to apply.” The Applicant has prepared a written statement supporting the Variance Criteria found in ACC 18.70.010(A), see Exhibit 14. The Applicant seeks to utilize the setbacks that apply to the R-5 zone. 2. Per ACC 18.70.010(A), variance requests from the requirements of ACC Title 18 ‘Zoning’ are to be heard and decided upon by the Hearing Examiner. The Hearing Examiner may approve with or without conditions. 3. The Valley Regional Fire Authority (“VRFA”) provided a written comment in regards to the request for 5-ft. side setbacks for the Project. The VRFA comments are as follows: “Review Comments: The review comments are to address the request for variance to the side yard setbacks of five feet. Fire Exposure: Five foot side yard setbacks create a fire exposure issues for neighbors on either side of the residence. Radiant heat will travel from the house on fire and ignite the siding of the neighboring residential structure without direct flame contact. Embers can also be carried on the air currents to the neighboring residences. This plat has steep slopes that create a path of travel for fire up hill to the next house. We have had houses in Lakeland Hills that have caught on fire due to being exposed to the neighbor’s house fire that had the five foot setbacks. Fire Rescue: Five foot side setbacks and fences on the property lines do not allow for ground ladder rescue or ladder access to any of the windows on the sides of these structures. Conditions: VRFA will recommend the setback variance with the condition that all residential structures install residential fire sprinkler systems.” Staff Analysis: Staff would like to point out that a majority of the City’s single-family residences are located within the R-5 and R-7 zoning districts which allow for 5-ft. side yard setbacks. The minimum lot size in the R-5 zone is 8,000 sq. ft. and the minimum lot size in the R-7 zone is 4,300 sq. ft.; the lots proposed in this Project are in the range of 10,115 sq. ft. to 21,490 sq. ft. Staff does not recommend all lots to be required to have residential fire sprinkler systems. North Ridgeview Estates Plat Hearing Examiner Packet Page 12 of 422 Agenda Subject: PLT17-0001, VAR17-0002, DEV17-0003, Preliminary Plat of North Ridgeview Estates and Variance to Development Standards (setbacks) Date: January 8, 2018 Page 13 of 29 Deviation Findings 1. Four deviation requests from the City of Auburn Engineering and Des ign Standards were requested by the Applicant, as follows: 1) to have a dead-end road longer than 800 ft.; 2) a reduction in the road centerline radius; 3) a reduction in the sag vertical curve length; and to, 4) allow a reduction in the minimum fire flow requirements. 2. The first request is to have Road A as a dead-end road longer than 800 ft. The proposal is to have Road A approximately 1,900 ft. in length as a dead-end public street. The City has required this “Residential Collector” to be built and will eventually be extended to the east to connect with 132nd Ave. SE. A temporary turnaround easement will be provided near the east terminus of Road A for emergency vehicles. 3. The second request is to have the road centerline radius for Road A be reduced fro m 544 ft. to 350 ft. as long as a design speed of 30 MPH is used for the sight distance requirements (as opposed to the standard of 35 MPH). 4. The third request is to have the sag vertical curve length for Road A reduced from 425 ft. to 100 ft. as long as additional lighting is provided at the intersection of Road A and 124th Ave. SE. 5. The fourth request is to have a reduction in the required fire flow from 1,500 gpm for 2-hours to 1,200 gpm for 2-hours. 6. Deviations from the Engineering and Design Standard s are subject to approval of the Hearing Examiner per ACC 17.18.010(A) which states (emphasis added): “A. The hearing examiner may approve a modification of any standard or specification established or referenced by Chapter 17.14 ACC or established or referenced in the city’s design standards or construction standards, upon making the findings of fact in ACC 17.18.030; provided, that the hearing examiner shall obtain the concurrence of the city engineer for any requests to modify any city of Auburn design or construction standard.” 7. The City Engineer has reviewed each of the four Deviation requests and conditionally recommend approval. See the City Engineer’s written recommendation, Reference Exhibit 15. III. CONCLUSIONS: Preliminary Plat Conclusions Staff recommends approval of the Preliminary Plat, with conditions. Per ACC 14.03.030, a preliminary plat is a Type III Decision which are quasi-judicial final decisions made by the Hearing Examiner. ACC 17.10.070 lists the approval criteria for a preliminary plat; the criteria are as follows (in italics) followed by Staff’s analysis: A. Adequate provisions are made for the public health, safety and general welfare and for open spaces, drainage ways, streets, alleys, other public ways, water supplies, sanitary wastes, par ks, playgrounds and schools; Staff Analysis: No adverse impacts to the public health, safety and general welfare are anticipated from the proposed subdivision. Staff offers the following analysis of each of the other items listed in this criterion: North Ridgeview Estates Plat Hearing Examiner Packet Page 13 of 422 Agenda Subject: PLT17-0001, VAR17-0002, DEV17-0003, Preliminary Plat of North Ridgeview Estates and Variance to Development Standards (setbacks) Date: January 8, 2018 Page 14 of 29 Open Spaces: As discussed at length in the ‘Findings of Fact’, above, the Project is providing over 15 acres of open space within the Site. The Urban Separator requirement for providing 50% open space is being met. Drainage Ways: No drainage ways appear to be located on the Site. A fish-bearing stream, Soosette Creek, is located to the off-site north of the site and 3 wetlands are present on the site. The stormwater from the Project will be evaluated and treated as necessary to meet the Department of Ecology Stormwater Management Manual for Western Washington (SWMM) and Auburn Supplements (e.g. adequate pre-treatment for stormwater entering Soosette Creek). Streets, Alleys, other Public Ways: The City’s Comprehensive Transportation Plan, Functional Roadway Classification Map, shows a future “Residential Connector” street extending through the Site, connecting 124th Ave. SE to 132nd Ave. SE. The Project will provide a segment of this Residential Collector, Road A, extending from 124th Ave. SE to the southeast corner of the Project, setting up the roadway for future extension when development occurs to the east. Two other Local Residential streets (cul-de-sacs), Road B and Road C, are provided off of Road A to provide access for Lots 12-19, and Lots 24-30, respectively. Lots 1-11 and 20-23 will take direct access from Road A. Lots 14 and 15 will utilize a joint-use-driveway off of Road B. No improvements to 124th Ave. SE are required with the exception of intersection improvements at the new intersection with Road A and dedication of 6 ft. of right-of-way (ROW). All roadways will be constructed to meet applicable engineering design and construction standards such as storm drainage, lighting, sidewalks, etc. With construction of the new roadways the City’s Transportation Division finds that there will be no decrease in the road network level of service (LOS). In addition, each new residence will be required to pay the Traffic Impact Fee in place at time of building permit issuance. There is an existing private driveway to the south of proposed Road A that will be removed and replaced, connecting to Road A across from Lot 11. The proposed replacement driveway will be 20-ft. wide and paved and placed within a new tract, Tract G. This driveway serves two existing uses, the Gurudwara Sacha Marg Sahib Temple (located on Parcel No. 332205-9017) and an existing City of Kent Water Reservoir Tank (Parcel No. 332205-9177). Relocation of the access point for these two uses will require them to be assigned new addresses off of the new Road A. This readdressing will occur along with the assignment of addresses for the Project during the final plat stage. Three Deviations have been requested for Road A, which the City Engineer has conditionally recommended for approval; see ‘Deviation Conclusions’, below. Public Water: The Site is served by Water District No. 111 and will provide adequate water for the Project. An off-site water extension from 132nd Ave. SE was required to serve the Project; this extension has since been completed in SE 285th St. (a private road), stubbing the water main to the eastern boundary of the Site. A Deviation to the fire flow requirements has been requested, as the Project is not located within the City of Auburn Water boundaries, and been recommended for conditional approval from the City Engineer; see ‘Deviation Conclusions’, below. Water District No. 111 has provided a certificate that they can provide 1,200 gpm for 2 hours. Public Sanitary Sewer: The Site is served by Soos Creek Sewer and Water District (for sewer only) and will provide adequate sanitary sewer service to the proposed subdivision. Parks, Playgrounds: No parks or playgrounds are proposed for the Project, and none are required; as there are not greater than 50 lots being created (ACC 17.14.100). Park Impact Fees will pay the applicable fee in place at the time of building permit issuance (currently $3,500.00 per unit). North Ridgeview Estates Plat Hearing Examiner Packet Page 14 of 422 Agenda Subject: PLT17-0001, VAR17-0002, DEV17-0003, Preliminary Plat of North Ridgeview Estates and Variance to Development Standards (setbacks) Date: January 8, 2018 Page 15 of 29 Schools: The Site is located within the Kent School District boundaries. Per the Applicant, students within the Project will attend: 1) Pine Tree or Horizon Elementary schools; 2) Mattson or Cedar Heights Middle schools; and, 3) Kentlake High School. Per the Applicant’s conversations with the Kent School District, a bus stop will be (re)established at or near the new intersection of 124th Ave. SE and Road A as outside of the Project, there are no safe walking routes for students to get to the schools. Reference the “School Access Analysis”, Exhibit 8. Note that the Kent School District was provided email notice on December 7, 2017 of the Project and no response was received. Staff therefore finds the Project meets this criterion, as conditioned herein. B. Conformance of the proposed subdivision to the general purposes of the comprehensive plan; Staff Analysis: The Project is consistent with the general purposes of the Comprehensive Plan. Specifically the Project is consistent with or implements the following objectives, goals, and policies: Land Use Policies: LU-2 As the market and utility availability enable denser development to occur, standards should be developed to maximize density while preserving open space and critical areas . The proposed subdivision is setting aside 50% of the Site as open space which includes critica l areas (wetlands/wetland buffers). LU-5 New residential development should contribute to the creation, enhancement and improvement of the transportation system, health and human services, emergency services, school system, and park system. This may be accomplished through the development of level of service standards, mitigation fees, impact fees, or construction contributions . The Project will be constructing a new segment of a Residential Collector street that will eventually connect two Minor Arterials (124th Ave. SE and 132nd Ave SE.) LU-6 Cluster development is the preferred form of residential development in all residential designations with the goal of preserving natural areas, critical areas, and areas that support low impact development. Where clustering accomplishes these objectives, it should not come at the expense of lost development potential. Variances to lot size, lot dimensions, building height, and other bulk or dimensional standards should be utilized in order to incentivize and promote preservation. The Project is making use of clustering, preserving open space and critical areas, while also providing 30 single-family residential lots. The Applicant has requested a Variance to setbacks as the Project is allowed to meet the R-5 lot size of 8,000 sq. ft., but also required to meet the R-1 setbacks; setbacks in this instance would be considered under “…other…dimensional standards…”. Capital Facilities Objective 1.1. To ensure that new development does not out-pace the City's ability to provide and maintain adequate public facilities and services, by allowing new development to occur only when and where adequate facilities exist or will be provided, and by encouraging development types and locations which can support the public services they require Policies: CF-1 Lands designated for urban growth by this Plan shall have an urban level of public facilities (sewer, water, storm drainage, and parks) prior to or concurrent with development. North Ridgeview Estates Plat Hearing Examiner Packet Page 15 of 422 Agenda Subject: PLT17-0001, VAR17-0002, DEV17-0003, Preliminary Plat of North Ridgeview Estates and Variance to Development Standards (setbacks) Date: January 8, 2018 Page 16 of 29 CF-2 Encourage development where new public facilities can be provided in an efficient manner. CF-4 If adequate facilities are currently unavailable and public funds are not committed to provide such facilities, developers must provide such facilities at their own expense in order to develop. CF-7 The City shall encourage and approve development only where adequate public services including police protection, fire and emergency medical services, education, parks and other recreational facilities, solid waste collection, and other governmental services are available or will be made available at acceptable levels of service prior to project occupancy or use. The Project is providing adequate public facilities: public water from Water District No. 111; public sewer from Soos Creek Sewer and Water District; providing stormwater management on-site including LID facilities; providing open space throughout the development; and, paying park, school, and other applicable impact fees. Objective 1.2. To ensure that new developments are supported by an adequate level of public services through an effective system of public facilities. Policies: CF-10 Public facilities shall be provided in accord with the guidance of the Capital Facilities Plan or, as may be appropriate a system plan for each type of facility designed to serve at an adequate level of service the locations and intensities of uses specified in this comprehensive plan. CF-11 No new development shall be permitted unless the facilities specified in each facility plan are available or can be provided at a level adequate to support the development. The adequacy of facilities shall be determined by the following: 1. An adopted system plan; 2. Policy guidance as provided in the City Capital Facilities Plan; 3. Appropriate engineering design standards as specified in applicable City Plans, Codes, and manuals as approved by the City Engineer; 4. Environmental review standards (adequacy includes the absence of an unacceptable adverse impact on a public facility system). 5. Case by case evaluation of the impacts of a proposed development on the public facility systems: first to determine the minimum amount of facilities necessary to support the development and second to determine a proportionate share of the system to be developed or financially guaranteed before approving the development. CF-12 No new development shall be approved which is not supported by a minimum of facilities to support the development and which does not provide for a proportionate share of related system needs. The proposed subdivision is providing adequate public facilities and will be designed to meet all applicable codes and standards applicable for development. Objective 1.6. To ensure that collection, conveyance, storage and discharge of storm drainage is provided in a sufficient and environmentally responsible manner, in order to meet the needs of the existing community and provide for its planned growth. Policies: CF-37 The City shall require developers to construct storm drainage improvements directly serving the development, including any necessary off-site improvements. North Ridgeview Estates Plat Hearing Examiner Packet Page 16 of 422 Agenda Subject: PLT17-0001, VAR17-0002, DEV17-0003, Preliminary Plat of North Ridgeview Estates and Variance to Development Standards (setbacks) Date: January 8, 2018 Page 17 of 29 The Project will provide adequate facilities for stormwater. Individual LID systems will be provided for each lot and a detention facility (pond) will be constructed for the remainder of the subdivision. The detention facility will be designed to ensure proper flow rates are provided to the existing wetlands as well as adequate treatment as the stormwater will also reach Soosette Creek to the north of the site. Staff therefore finds the Project meets this criterion, as conditioned herein. C. Conformance of the proposed subdivision to the general purposes of any other applicable policies or plans which have been adopted by the city council; Staff Analysis: The preceding analysis for Criterion B demonstrates the Project’s consistency with the City of Auburn Capital Facilities Plan, Comprehensive Storm Drainage Plan, and the Parks, Recreation and Open Space Plan. The Project is also consistent with the general purposes of the Comprehensive Transportation Plan. Specifically, the Project is consistent with the following Plan elements: Connect-01: An efficient transportation system seeks to spread vehicle movements over a series of planned streets. The goal of the system is to encourage connectivity while preventing unacceptably high traffic volumes on any one street. Ample alternatives should exist to accommodate access for emergency vehicles. For these reasons the City will continue to plan a series of collectors and arterials designed to national standards to provide efficient service to the community. GMA-01: Require developments to construct or finance transportation improvements and/or implement strategies that mitigate the impacts of new development concurrent with (withi n 6 years of) development, as required by the Growth Management Act. Funding-01: Require developments or redevelopments to construct transportation infrastructure systems needed to serve new developments. Funding-03: Improvements that serve new developments will be constructed as a part of the development process. All costs will be borne by the developer when the development is served by the proposed transportation improvements. In some instances, the City may choose to participate in this construction if improvements serve more than adjacent developments. ROW-01: The acquisition and preservation of right-of-way is a key component of maintaining a viable transportation system. Methods used to acquire and preserve right -of-way include: - Requiring dedication of right-of-way as a condition of development; - Purchasing right-of-way at fair market value; and - Acquiring development rights and easements from property owners. Street-07: The Functional Roadway Classifications Map shall serve as the adopted standard for identifying classified streets in the City of Auburn and the potential annexation areas. Ped-03: Require developers to incorporate pedestrian facilities into new development and redevelopment in conformance with the Auburn City Code. As analyzed in Criterion A, above, and within the ‘Preliminary Plat Findings’, above, the Project is required to construct a new Residential Collector street through the Site. This is a requirement of the Comprehensive Transportation Plan’s Functional Classifications Map. In addition two other roadways, Road B and Road C, will connect to Road A within the Project. Road B and Road C (cul-de-sacs) are North Ridgeview Estates Plat Hearing Examiner Packet Page 17 of 422 Agenda Subject: PLT17-0001, VAR17-0002, DEV17-0003, Preliminary Plat of North Ridgeview Estates and Variance to Development Standards (setbacks) Date: January 8, 2018 Page 18 of 29 both classified as Local Residential streets and will be constructed as such. The Developer is fully responsible for constructing everything within the Project site including all roadways. All roadways will include all necessary facilities including, but not limited to, storm drainage, lighting, and sidewalks. Three Deviations to Road A have been requested by the Applicant. These Deviations have been reviewed by the City Engineer and recommended to be conditionally approved; see ‘Deviation Conclusions’, below, and Exhibit 15. Per Chapter 12.64A ACC ‘Required Public Improvements’ no improvements to 124th Ave. SE are required as a new public street is being constructed to an existing public street (as opposed to an “access point” which for instance would be a driveway). No off-site improvements to the City’s road network are required. Staff therefore finds the Project meets this criterion, as conditioned herein. D. Conformance of the proposed subdivision to the general purposes of this title, as enumerated in ACC 17.02.030: Staff Analysis: The proposed subdivision meets the general purposes of Title 18 ACC ‘Land Adjustments and Subdivisions’. The enumerated list found in ACC 17.02.030 is a follows (in italics) including Staff’s analysis for each item. “The purpose of this title is to regulate the division of land lying within the corporate limits of the city, and to promote the public health, safety and general welfare and prevent or abate public nuisances in accordance with standards established by the state and the city, and to: A. Prevent the overcrowding of land; The Project is providing 15 acres of open space on 29.7-acre Site and clustering the lots (as much as feasible) which would not be considered overcrowding of the land. B. Promote safe and convenient travel by the public on streets and highways; The Project is constructing a new Residential Collector through the Site which will eventually connect 124th Ave. SE and 132nd Ave. SE and therefore is providing a means of safe and convenient travel. C. Promote the effective use of land; The Site is located within the R-1 zoning district and overlain by the Urban Separator Overlay and is required to set aside 50% of the site as open space. Based on the density for the R-1 zone, 1 unit per acre, the Project is effectively developing the Site by maximizi ng the number of residential units that are allowed. D. Provide for adequate light and air; The Project will provide adequate light and air through the applicable setback and lot coverage development standards. E. Facilitate adequate provision for water, sewerage, storm drainage, parks and recreational areas, sites for schools and school grounds, and other public requirements; North Ridgeview Estates Plat Hearing Examiner Packet Page 18 of 422 Agenda Subject: PLT17-0001, VAR17-0002, DEV17-0003, Preliminary Plat of North Ridgeview Estates and Variance to Development Standards (setbacks) Date: January 8, 2018 Page 19 of 29 The Project is providing: pubic water from Water District No. 111; public sewer from Soos Creek Sewer and Water District; adequate storm drainage provisions by meeting the SWMM and Auburn Supplement; parks and recreational areas by paying Park Impact Fees and providing open space within the Project; payment of applicable School Impact Fees (Kent School District); and, other public requirements such as roads and fire protection. F. Identify, preserve, and utilize native soils and/or vegetation for the purposes of reducing storm water discharges, promoting groundwater infiltration, and implementing the use of storm water low impact development techniques; The Project will be preserving native soils and vegetation by setting aside 50% of the site as open space and utilizing LID techniques for the future homes and a combined detention/wetpool for the detention facility (pond). G. Provide for proper ingress and egress; The Project will provide proper ingress and egress for each individual future home and a connection to the public road network via Road A to 124th Ave. SE. H. Provide for the expeditious review and approval of proposed land divisions which comply with this title, the Auburn zoning ordinance, other city plans, policies and land use controls, and Chapter 58.17 RCW; The Project has moved expeditiously through the public review process with the City and Applicant working with each other to help the Project proceed. I. Adequately provide for the housing and commercial needs of the citizens of the state and city; The Project will eventually provide for 30 new single-family residences to serve future populations. J. Require uniform monumenting of land divisions and conveyance by accurate legal description; Upon final plat map review, the Project will be required to meet all applicable survey requirements. K. Implement the goals, objectives and policies of the Auburn Comprehensive Plan.” As analyzed in Criteria B and C, above, the Project successfully implements the Comprehensive Plan. Staff therefore finds the Project meets this criterion, as conditioned herein. E. Conformance of the proposed subdivision to the Auburn zoning ordinance and any other applicable planning or engineering standards and specifications as adopted by the city, or as modified and approved as part of a previously approved PUD; Staff Analysis: As analyzed in the ‘Preliminary Plat Findings’, above, the Project is able to meet applicable zoning and engineering standards, if the requested Variance, Plat Modification, and Deviations, are approved with this Preliminary Plat. North Ridgeview Estates Plat Hearing Examiner Packet Page 19 of 422 Agenda Subject: PLT17-0001, VAR17-0002, DEV17-0003, Preliminary Plat of North Ridgeview Estates and Variance to Development Standards (setbacks) Date: January 8, 2018 Page 20 of 29 The future residences will be required to meet the development standards, such as setbacks, that are approved along with this final plat. In the event the Variance for setbacks is not approved, the residences would need to meet the R-1 setbacks. If the Plat Modification request is not approved, the Applicant would need to substantially redesign the proposed subdivision. The Deviation requests for Road A are recommended for approval by the City Engineer. All other engineering standards and specifications will be reviewed for consistency upon submittal of the FAC. The Site is not part of a planned unit development (PUD). Staff therefore finds that the Project is able to meet this criterion, as conditioned herein. F. The potential environmental impacts of the proposed subdivision are mitigated such that the preliminary plat will not have an unacceptable adverse effect upon the quality of the environment; Staff Analysis: There are 3 wetlands on the site which will be permanently protected by being placed in tracts upon approval of the final plat , including the required 25-ft. wetland buffers. The wetlands and their buffers are proposed for enhancement, only the buffers are required to be enhanced as they have been previously disturbed (mowed), per ACC 16.10.090(A). The proposed storm drainage facility (pond) has been preliminarily reviewed for providing proper hydrology to these wetlands. Reference the Preliminary Stormwater Site Plan, Section 5.0-G (Exhibit 10), Critical Areas Report (Exhibit 11), and Wetland Hydraulic Support letter (Exhibit 10). A fish-bearing steam, Soosette Creek, is located north of the site and appears to be hydrologically connected to the Site via the on-site wetlands. As such, the stormwater will be treated as required by the SWMM, as conditioned herein. The northern portion of the site slopes down from south to north with slopes in the ranges of 10-20%. With implementation and observance of BMPs and the proposed plat conditions, the Project will not have significant adverse impacts. Staff therefore finds the Project meets this criterion, as conditioned herein. G. Adequate provisions are made so the preliminary plat will prevent or abate public nuisances; Staff Analysis: Adequate provisions are made so the proposed Project will prevent or abate public nuisances. As the Site is mainly undeveloped, there are no active code violation cases for the site and no known public nuisances. There has been some past issues with vagrants occupying the two barns on-site, which will be demolished. In the future, the proposed construction of the Project will be reviewed as part of the FAC, Grading, Storm, and Building Permit applications and plans to be submitted by the Applicant. With construction consistent with subsequent City approvals, the creation of public nuisances will be prevented . Staff therefore finds the Project meets this criterion, as conditioned herein. H. Lot configuration, street and utility layouts, and building envelopes shall be designed in a manner that identifies, preserves, and utilizes native soils and/or vegetation that are integrated into a low impact development facility, consistent with the city’s adopted storm water management manual. North Ridgeview Estates Plat Hearing Examiner Packet Page 20 of 422 Agenda Subject: PLT17-0001, VAR17-0002, DEV17-0003, Preliminary Plat of North Ridgeview Estates and Variance to Development Standards (setbacks) Date: January 8, 2018 Page 21 of 29 Staff Analysis: The proposed subdivision has been designed to retain native soils and vegetation to the most feasible extent possible. As stated above, 15 acres of open space are being provid ed and most of the soils and vegetation in these areas will be either retained or restored. LI D facilities for the lots are proposed; LID is not feasible for the other developed areas (e.g. roads) due to the soil types, slopes, and groundwater elevations. A Preliminary Stormwater Site Plan (SSP) has been prepared and reviewed by the City; a final SSP will be submitted for review along with the FAC. Staff therefore finds the Project meets this criterion, as conditioned herein. Plat Modification Conclusions Staff recommends approval of the Plat Modification, with no conditions. Per ACC 17.18 ‘Modifications of Standards and Specifications’, the Hearing Examiner may approve a modification of any standard or specification established or referenced by ACC 17.14 ‘Improvement Requirements – Subdivisions’. ACC 17.14.090 then lists the requirements for lots (i.e. size, shape, etc.) and references the cluster subdivision regulations of Chapter 17.26 ACC and the lot size requirements of ACC Title 18 ‘Zoning’; the Hearing Examiner therefore may approve a plat modification request for the clustering requirements upon making the findings of fact listed in ACC 17.18.030. The Applicant has requested a plat modification from the following Code section regarding clustering of the lots within the Project: “ACC 17.26.030(D) 5. Lot Size. The lot area of individual building lots within a cluster subdivision or short subdivision shall be no less than that provided for in Chapter 18.07 ACC, as modified by Chapter 18.21 ACC. New lots created by any subdivision or short subdivision action shall be clustered in groups not exceeding eight units. There may be more than one cluster per project. Separation between cluster groups shall be a minimum of 120 feet.” The Applicant has prepared a written statement addressing this plat modification and its conformance with approval criteria, see Exhibit 13. ACC 17.18.030 lists the findings that the Hearing Examiner must make for a plat modification; the criteria are as follows (in italics) followed by Staff’s analysis: A. Such modification is necessary because of special circumstances related to the size, shape, topography, location or surroundings of the subject property, to provide the owner with development rights and privileges permitted to other properties in the vicinity and in the zoning district in which the subject property is located; Staff Analysis: The property itself is a special circumstance being that it is the first proposal to utilize the cluster subdivision requirements; which are required as the Site is located within the R-1 zone and within the Urban Separator Overlay. The Site itself has special circumstances such as the critical areas in the northern portion and the fact that a new Residential Collector street is required, essentially bisecting the site. The design of the Residential Collector posed challenges due to the slope and underlying soils and groundwater levels. Approving this plat modification request would provide the Applicant with similar privileges to other properties with the same zoning and overlay applied as those properties would not likely need to include an extension of a collector roadway through them. Staff therefore finds the Project meets this criterion. North Ridgeview Estates Plat Hearing Examiner Packet Page 21 of 422 Agenda Subject: PLT17-0001, VAR17-0002, DEV17-0003, Preliminary Plat of North Ridgeview Estates and Variance to Development Standards (setbacks) Date: January 8, 2018 Page 22 of 29 B. That, because of such special circumstances, the development of the property in strict conformity with the provisions of this title will not allow a reasonable and harmonious use of the property; Staff Analysis: If the plat modification request was denied, the feasibility of the Project would be minimal due to the Residential Collector being required through the Site. By approving the plat modification request, it would allow the Site to be developed as a residential subdivision—which is the preferred use of the Site. Staff therefore finds the Project meets this criterion. C. That the modification, if granted, will not alter the character of the neighborhood, or be detr imental to surrounding properties in which the property is located; Staff Analysis: Properties surrounding the Site, with the exception of the high school to the south, are residential. The proposed subdivision will be compatible with, and complement, the surrounding neighborhood. Staff therefore finds the Project meets this criterion. D. Such modification will not be materially detrimental to the implementation of the policies and objectives of the comprehensive land use, transportation and utility comp rehensive plans of the city; Staff Analysis: Approval of the plat modification request will not have any detrimental effects on any of the City’s comprehensive plans, as analyzed under ‘Preliminary Plat Conclusions’, above. The plat modification, in fact, is implementing the Comprehensive Transportation Plan by facilitating construction of the new Residential Collector roadway. Staff therefore finds the Project meets this criterion. E. Literal interpretation of the provisions of this title would deprive the applicant of rights commonly enjoyed by other properties in the same zoning district; Staff Analysis: As analyzed under Criterion A, above, the plat modification request is necessary due to the Residential Collector roadway being required to be const ructed through the Site. Per the Functional Roadway Classification map, no other properties within the R-1 zone / Urban Separator Overlay show a new roadway through the middle of them. Future extension of the Residential Collector to the east will go along the south property lines of the properties to the east, eventually merging with SE 288th St. and connecting to 132nd Ave. SE. Staff therefore finds the Project meets this criterion. F. The approval of the modification will be consistent with the purpose of this title; Staff Analysis: The purpose of Title 17 ACC ‘Land Adjustments and Divisions’ is shown and analyzed in Criterion D, above, under ‘Preliminary Plat Conclusions’. The approval of this plat modification request is found to be consistent with the purposes of this title. Staff therefore finds the Project meets this criterion. G. The modification cannot lessen the requirements of the zoning ordinance. Any such modi fication must be processed as a variance pursuant to ACC 18.70.010. North Ridgeview Estates Plat Hearing Examiner Packet Page 22 of 422 Agenda Subject: PLT17-0001, VAR17-0002, DEV17-0003, Preliminary Plat of North Ridgeview Estates and Variance to Development Standards (setbacks) Date: January 8, 2018 Page 23 of 29 Staff Analysis: The plat modification request is not modifying any requirements of Title 18 ACC ‘Zoning’. Staff therefore finds the Project meets this criterion. Variance Conclusions Staff recommends approval of the Variance, with no condition s. The Applicant has requested a Variance from the following Code section regarding setbacks within the Project: “ACC 18.21.010(F) 3. The minimum size of any lot shall be 8,000 square feet. For lots less than 35,000 square feet, the minimum lot width shall be consistent with the requirements of the R-5 zone (Chapter 18.07 ACC). All other applicable development standards related to the R-1 zone will continue to apply.” The Variance request is to utilize the setbacks of the R-5 zone, as the lot size requirements of the R-5 zone are allowed per this Code section. According to the Applicant, applying the R-1 setbacks (which are for 35,000 sq.-ft. minimum lot sizes) to an R-5 sized lot (8,000 sq.-ft. minimum lot size) would severely limit the development potential of the Site and the proposed lots within the Project. The Applicant has prepared a written statement the Variance Criteria found in ACC 18.70.010(A), see Exhibit 14. Per ACC 14.03.030, Variances are a Type III Decision which is a quasi-judicial final decision made by the Hearing Examiner ACC 18.70.010(A), ‘Variances’, specifies that the Hearing Examiner may approve or modify and approve an application for a Variance if the application satisfies all of the approval criteria specified in ACC 18.70.010(A)(1) thru (10). Following is a staff analysis of this Variance application’s compliance with each criterion; the criteria are as follows (in italics) followed by Staff’s analysis: 1. That there are unique physical conditions including narrowness or shallowness of lot size or shape, or exceptional topographical or other physical conditions peculiar to and inherent in the particular lot; and that, as a result of such unique physical conditions, practical difficulties or unnecessary hardships arise in complying with provisions of this title. Staff Analysis: The unique physical characteristics of the property are as follows: - A new Residential Collector is required to be extended through the Site, essentially bisecting the Site; - Due to the topography of the site and the underlying soils and groundwater, design of the Residential Collector requires extensive grading and limits the areas for stormwater management; - 50% of the site is required to be set-aside as open space which restricts the development area to the other 50%; and, - The northern portion of the site includes three wetlands that appear to extend to the properties to the north where there is a fish-bearing stream (Soosette Creek). Due to these physical encumbrances on the Site, the Development potential of the Site would be severely limited if a reduction in the setbacks was not approved. North Ridgeview Estates Plat Hearing Examiner Packet Page 23 of 422 Agenda Subject: PLT17-0001, VAR17-0002, DEV17-0003, Preliminary Plat of North Ridgeview Estates and Variance to Development Standards (setbacks) Date: January 8, 2018 Page 24 of 29 Staff therefore finds the Project meets this criterion. 2. That, because of such physical conditions, the development of the lot in strict conformity with the provisions of this title will not allow a reasonable and harmonious use of such lot. Staff Analysis: The applicable development standards for the R-1 and R-5 zone are as follows: Development Standard R-1 R-5 Minimum Avg. Lot Area 35,000 SF 8,000 SF Minimum Lot Area 35,000 SF 6,000 SF Minimum Lot Width 125 Ft. 50 Ft. Minimum Setbacks Front, House 35 Ft. 10 Ft. Front, Garage 20 Ft. 20 Ft. Side, Interior 10 Ft. 5 Ft. Side, Street 20 Ft. 10 Ft. Rear 35 Ft. 20 Ft. The lot averaging requirements that apply to the Urban Separator Overlay set the minimum lot size at 8,000 sq. ft. and the dimension requirements consistent with the R-5 zone. By requiring the setbacks of the R-1 zone on what is essentially an R-5 lot, a harmonious use of the lot would be difficult to achieve as it would leave a very limited building envelope for the homes. Staff therefore finds the Project meets this criterion. 3. That the variance, if granted, will not alter the character of the neighborhood, or be detrimental to surrounding properties in which the lot is located. For nonconforming single-family homes, this finding is determined to be met if the features of the proposed variance are consistent with other comparable features within 500 feet of the proposal. Staff Analysis: There are no indications that a reduction in setbacks for the Project would be detrimental to the neighborhood or surrounding properties. The surrounding residenti al properties are a mix of homes on several-acre properties down to 3,900 sq.-ft. lots about 1/3 of a mile to the south (“The Bridges” development in the island of Kent surrounded by the City of Auburn). Staff therefore finds the Project meets this criterion. 4. That the special circumstances and conditions associated with the variance are not a result of the actions of the applicant or previous owners. Staff Analysis: The special circumstances and conditions associated with the Variance are a result of the Applicant proposing a subdivision; however, the property is zoned for residential development and therefore a subdivision proposal is expected. The other special circumstances have been discussed in Criteria 1 through 3, above; specifically, the Project is required to construct a new Residential Collector street through the Site, and, due to existing naturally occurring circumstances , extensive grading is required for the roadway, and 50% of the site is required to be set aside as open space. Staff therefore finds the Project meets this criterion. 5. Literal interpretation of the provisions of this title would deprive the applicant of rights commonly enjoyed by other properties in the same zoning district. North Ridgeview Estates Plat Hearing Examiner Packet Page 24 of 422 Agenda Subject: PLT17-0001, VAR17-0002, DEV17-0003, Preliminary Plat of North Ridgeview Estates and Variance to Development Standards (setbacks) Date: January 8, 2018 Page 25 of 29 Staff Analysis: As analyzed in Criteria 1 through 4, above, compliance with the setbacks of the R-1 zone on a R-5 sized lots would deprive the Applicant of development rights that are, or could be, enjoyed by other properties that are zoned R-1 and located wholly or partially within the Urban Separator Overlay. Staff therefore finds the Project meets this criterion. 6. The approval of the variance will be consistent with the purpose of this title and the zoning district in which the property is located. Staff Analysis: Approval of the setback Variance would not be inconsistent with the purpose of Title 18 ACC ‘Zoning’ as the proposed lots are much smaller than the 35,000 sq.-ft. requirement of the R-1 zone and the request to use R-5 setbacks is consistent with the lot sizes proposed. The intent of the R-1 zoning district is “…to provide areas for estate-type residential development on large lots. This zone would normally be located in the areas particularly suited for such development.” This intent, however, seems to be inconsistent with the requirements of the Urban Separator Overlay which requires both lot averaging and clustering, where the minimum lot size is 8,000 sq. ft. The requirement to provide for 50% of open space does perhaps help offset the smaller lot sizes and help give the feel of an “estate-type residential development”. Allowing these smaller lot sizes, however, should also allow the use of lesser setbacks. Staff therefore finds the Project meets this criterion. 7. The variance will not allow an increase in the number of dwelling units permitted by the zoning district. Staff Analysis: The Variance for setbacks does not impact the number of units. Staff therefore finds the Project meets this criterion. 8. The authorization of such variance will not adversely affect the comprehensive plan. Staff Analysis: There is nothing apparent in the Comprehensive Plan that speaks to setbacks in the R-1 or Urban Separator, and therefore, the Variance request will not adversely affect the Comprehensive Plan. Per the “Urban Separator” overlay designation in the Comprehensive Plan Land Use Element, cluster subdivisions are required for subdivision proposals. Staff therefore finds the Project meets this criterion. 9. The variance shall not allow a land use which is not permitted under the zoning district in which the property is located. Staff Analysis: The Variance request for reduced setbacks has no impact on the uses proposed within the Project, that being said the Project is for single-family residential which are a Permitted use. Staff therefore finds the Project meets this criterion. 10. The variance shall not change any regulations or conditions established by surface mining permits, administrative use permits, conditional use permits or contract rezones authorized by the city council. Staff Analysis: The Site is not encumbered by any Surface Mining Permits, Administrative Use Permits, Conditional Use Permits, or Contract Rezones. North Ridgeview Estates Plat Hearing Examiner Packet Page 25 of 422 Agenda Subject: PLT17-0001, VAR17-0002, DEV17-0003, Preliminary Plat of North Ridgeview Estates and Variance to Development Standards (setbacks) Date: January 8, 2018 Page 26 of 29 Staff therefore finds the Project meets this criterion. Deviation Conclusions The City Engineer has reviewed the requested Deviations and conditionally recommended approval of all four. Per ACC 17.18 ‘Modifications of Standards and Specifications’, the Hearing Examiner may approve a modification of any standard or specification established or referenced by ACC 17.14 ‘Improvement Requirements – Subdivisions’. Further, the City Engineer shall make a recommendation to the Hearing Examiner on any modifications requested from the City of Auburn Engineering Design Standards (“COADS”). This process is referred to as a “Deviation” per Section 1.06 of the COADS. Four Deviations were requested: 1. Request for a dead-end road longer than 800-feet; 2. Request to reduce to the road centerline radius from 544-feet to 350-feet; 3. Request to reduce the sag vertical curve length from 425-feet to 100-feet; and, 4. Request for a reduction in the minimum fire flow requirements from 1,500 gpm for 2-hours to 1,200 gpm for 2-hours. See Exhibit 15 for the City Engineer’s written evaluation and recommendation of the Deviation requests. IV. STAFF RECOMMENDATION: Staff recommends approval of the Preliminary Plat, Plat Modification, Variance, and Deviations, based upon compliance with the project description and materials provided with the applications and subject to the ‘Conditions of Approval’ set forth below. Any deviations from the project description, exhibits, timing, or conditions must be reviewed and approved by the City of Auburn for conformity with this approval. Any change from these may require administrative or Hearing Examiner approval of changes to the permit and/or environmental review. Staff reserves the right to supplement the record of the case to respond to matters and information raised subsequent to the writing of this report V. CONDITIONS OF APPROVAL: 1. The Site is in Groundwater Protection Zone 4. All approvals and permits related to the Project and issued by the City shall be consistent with best management practices (BMPs) per ACC 16.10.120(E)(2). 2. A final wetland buffer enhancement (mitigation) plan for the three on-site wetlands shall be prepared and submitted with the civil (FAC) plans and consistent with Chapter 16.10 ACC. The wetlands and their associated 25-ft. buffers shall be placed in separate tracts on which development is prohibited, and protected by execution of an easement dedicated to the City. The easement shall grant the City access to on-site mitigation areas for the purposes of monitoring, maintaining, preserving, and enhancing the on-site wetlands and associated buffer areas, but not the obligation to. The location and limitations associated with the wetlands and their buffers shall be shown on the face the final plat. North Ridgeview Estates Plat Hearing Examiner Packet Page 26 of 422 Agenda Subject: PLT17-0001, VAR17-0002, DEV17-0003, Preliminary Plat of North Ridgeview Estates and Variance to Development Standards (setbacks) Date: January 8, 2018 Page 27 of 29 3. Civil Site Plan Improvement (FAC) approval will not be provided by the City of Auburn until approval for the construction drawings is obtained from King County Water District No. 111 (for public water) and Soos Creek Sewer and Water District (for public sewer). The Applicant shall provide approved plans from the noted jurisdictions to the City of Auburn once obtained. 4. The proposed 20-ft. wide asphalt driveway (Tract G) to the Gurudwara Sacha Marg Sahib Temple and City of Kent Water Tanks parcels shall be marked with “No Parking – Fire Lane”. Posting shall be in accordance with ACC and City of Auburn Engineering Design Standards. 5. Per ACC 12.12.030, property owners are responsible for maintaining right-of-way landscaping where they abut the public street. The proposed plat will have right-of-way landscaping where no lots have frontage; therefore, the Homeowner’s Association shall be responsible for the landscape maintenance in these areas. The landscape maintenance shall be consistent with the requirements of the ACC. 6. All areas within the proposed open space tracts that are disturbed shall be restored to a state similar to, or better than, what was existing prior to the disturbance. 7. The Homeowner’s Association shall be responsible for maintenance of all open space areas within the proposed tracts. A note shall be placed on the final plat stating as such, as well as a restriction for no modifications to the open spaces without approval from the City of Auburn. The maintenance responsibility shall also be addressed in the CC&R’s. 8. The proposed gravel trail / sewer maintenance road shown on Tract D shall be delineated on the final plat map and a note placed stating the right for pedestrian use. The Homeowner’s Association shall be responsible for maintenance of said trail. The maintenance responsibility shall also be addressed in the CC&R’s. 9. The following note, or functional equivalent, as determined by the City Engineer, shall be provided on the final plat: WHEN IT BECOMES NECESSARY, AS PART OF A SUBDIVISION, TO INSTALL A TEMPORARY CUL-DE-SAC PER CITY OF AUBURN DESIGN STANDARDS, THE PORTION OF THE TEMPORARY CUL-DE-SAC ENCROACHING ON THE ADJACENT PRIVATE PROPERTY SHALL BE PLACED IN A TEMPORARY EASEMENT DEDICATED TO THE CITY OF AUBURN. THE TEMPORARY EASEMENT SHOWN ON THE LOTS IS HEREBY RESERVED, GRANTED AND CONVEYED TO THE CITY OF AUBURN FOR TEMPORY PUBLIC ROADWAY PURPOSE, UPON THE RECORDING OFTHIS PLAT. THE CITY OF AUBURN IS HEREBY RESPONSIBLE FOR THE MAINTENANCE OF THE TEMPORARY PUBLIC ROADWAY FACILITIES WITHIN SAID EASEMENT. UPON THE CONSTRUCTION OF AN EXTENSION OF THE STREET, AND WHEN DETERMINED BY THE CITY OF AUBURN THAT THE TEMPORARY CUL-DE-SAC IS NO LONGER REQUIRED, IT SHALL BETHE RESPONSIBILITY OF THE DEVELOPER THAT IS EXTENDING THE PUBLIC STREET IMPROVEMENTS, TO REMOVE THE TEMPORARY CUL-DE-SAC AT THEIR EXPENSE. IN CONJUNCTION WITH TEMPORARY CUL-DE-SAC REMOVAL, THE DEVELOPER SHALL ALSO FINISH CONSTRUCTION OF THE PUBLIC STREET WITHIN THE TEMPORARY CUL- DE-SAC AREA IN ACCORDANCE WITH THE CITY OF AUBURN DESIGN STANDARDS APPLICABLE TO THE STREET CLASSIFICATION, AS WELL AS ANY PRIVATE IMPROVEMENTS AND PROPERTY RESTORATION THAT MAY BE NECESSARY ON ADJACENT LOT(S) AFFECTED BY THE REMOVAL OF THE TEMPORARY CUL-DE-SAC.THE TEMPORARY EASEMENT SHALL AUTOMATICALLY TERMINATE UPON REMOVAL OF THE TEMPORARY CUL-DE-SAC IMPROVEMENTS, AS APPROVED BY THE CITY OF AUBURN. North Ridgeview Estates Plat Hearing Examiner Packet Page 27 of 422 Agenda Subject: PLT17-0001, VAR17-0002, DEV17-0003, Preliminary Plat of North Ridgeview Estates and Variance to Development Standards (setbacks) Date: January 8, 2018 Page 28 of 29 10. Prior to City approval of the construction plans under the Facilities Extension Agreement (FAC), the plans shall show that appropriate portions of public streets shall be posted no parking on the appropriate portions of the streets due to its road width or presence of medians. Also, the cul-de-sacs shall be posted “No Parking” around their entire perimeter. Posting shall be in accordance with ACC and City of Auburn Engineering Design Standards. 11. Prior to City approval of the construction plans under the Facilities Extension Agreement (FAC), the Applicant shall provide documentation of application to the Washington State Department of Ecology (WSDOE) for a General Storm Permit, as required for all projects over one (1) acre in size. 12. A note shall be placed on the Final Plat indicating that the North Ridgeview Estates Homeowner’s Association and its heirs and successors shall maintain those portions of the tracts containing stormwater ponds and specifically the portions located outside the fenced pond boundaries, or if no fence is provided, outside the 10-year stormwater surface elevation, as determined by the City Engineer. Additionally, the Covenants, Conditions, and Restrictions (CC&Rs) to be reviewed by the City shall also address this maintenance responsibility. 13. If groundwater is encountered during construction in the proposed detention pond that appears that it will impact the live storage capacity of the detention pond, the City of Auburn will stop construction and require redesign of the facility as necessary to account for observed groundwater. Depending on the groundwater seepage rates encountered, elevation observed, the time of year, or other possible factors involved, construction may not commence again until an updated pond design is approved by the City of Auburn. 14. Clearing and grading shall be limited to between April 1st and October 31st unless the geologic hazard report specifically addresses measures necessary to perform clearing and grading during other portions of the year. 15. There shall be limited use of retaining walls so as to minimize the disturbance or alteration of existing natural slope areas, and are preferred over graded slopes. 16. Low impact development (LID) stormwater facilities are proposed throughout the Project in common areas including but not limited to dispersion trenches, drywells, and perforated downspout drains. An Operation and Maintenance Manual shall be prepared by the Design Engineer and utilized by the North Ridgeview Estates Homeowner’s Association. A Stormwater Maintenance and Easement Agreement will be on the final plat to maintain the LID facilities. 17. Interior side slopes of the proposed detention pond shall not be steeper than 3H:1V regardless of a fence being provided. 18. The preliminary plat materials currently show basic stormwater treatment for the proposed project. The plat shall provide stormwater phosphorus treatment per Volume V, Section 3.3 of the current Stormwater Management Manual for Western Washington because the receiving water (Soosette Creek) is listed is a waterbody reported under Section 305(b)/303(d) of the Clean Water Act. 19. The Plat Modification request for clustering, as required by ACC 17.26.030(D), is approved with no conditions. 20. The Variance request for reduced setbacks is approved, with no conditions. The applicable setbacks to the plat shall be consistent with the R-5 zoning district and a note shall be placed on the final plat stating as such. North Ridgeview Estates Plat Hearing Examiner Packet Page 28 of 422 Agenda Subject: PLT17-0001, VAR17-0002, DEV17-0003, Preliminary Plat of North Ridgeview Estates and Variance to Development Standards (setbacks) Date: January 8, 2018 Page 29 of 29 21. The Deviation request for a dead-end road longer than 800-feet is a deviation the City Engineer can support and recommend the Hearing Examiner approves due to the existing development patterns and future plans to extend a public road through the adjacent parcel. “No outlet” signage shall be provided at the intersection of the new road (Road A) and 124th Ave. SE. 22. The Deviation request to reduce to the road centerline radius from 544 ft. to 350 ft. is a deviation the City Engineer can support and recommend the Hearing Examiner approves as long as a design speed of 30 MPH is used for the sight distance requirements. 23. The Deviation request to reduce the sag vertical curve length from 425 ft. to 100 ft. is a deviation the City Engineer can support and recommend the Hearing Examiner approves as long as fixed/additional lighting is provided at the intersection with 124th Ave. SE. 24. The Deviation request to reduce the fire flow requirements from 1,500 gpm for 2 hours to 1,200 gpm for 2 hours is a deviation the City Engineer and Valley Regional Fire Authority can support and recommend the Hearing Examiner approves. The minimum required in the 2015 International Fire Code is 1,000 gpm for 1 hour. VI. EXHIBIT LIST: Exhibit 1. Staff Report Exhibit 2. Vicinity Map Exhibit 3. Land Use Application Forms Exhibit 4. SEPA DNS, Notice of Application, and Notice of Public Hearing, SEPA Checklist, and Noticing Documents Exhibit 5. Written Comments Received Exhibit 6. Preliminary Civil Plans, prepared by Barghausen Consulting Engineers, 11/2/2017 Exhibit 7. Traffic Impact Analysis (less the following sections which are available upon request: “Site Plans/Figures”, “Level of Service Calculations”, and “Peak Hour Counts” (pages 12-28)), prepared by Geralyn Reinart, PE, 3/2017 Exhibit 8. School Access Analysis Exhibit 9. Geotechnical Report and Comment Responses, prepared by Earth Solutions NW, multiple prepare dates Exhibit 10. Preliminary Stormwater Site Plan, prepared by Barghausen Consulting Engineers, 11/16/2017 (less the following section which are available upon request: “Basin Reconnaissance Report”, “Inventory Report”, modeling calculation sheets, geotechnical report, and critical areas report); and, Wetland Hydrologic Support, prepared by Sewall Wetland Consultants, 11/15/2017 Exhibit 11. Critical Areas Report, prepared by Sewall Wetland Consultants, 4/26/2017 Exhibit 12. Preliminary Wetland and Buffer Mitigation Plans, prepared by Sewall Wetland Consultants, 5/4/2017 Exhibit 13. Plat Modification Request Written Statement Exhibit 14. Variance Request Written Statement Exhibit 15. Deviation Requests – City Engineer Recommendation, 1/8/2018 North Ridgeview Estates Plat Hearing Examiner Packet Page 29 of 422 -This page left intentionally blank- North Ridgeview Estates Plat Hearing Examiner Packet Page 30 of 422 EXHIBIT 2 VICINITY MAP North Ridgeview Estates Plat Hearing Examiner Packet Page 31 of 422 -This page left intentionally blank- North Ridgeview Estates Plat Hearing Examiner Packet Page 32 of 422 0.5 NAD_1983_StatePlane_Washington_North_FIPS_4601_Feet Miles0.50.30 Vicinity Map 1/8/2018Printed Date: Map Created by City of Auburn eGIS Imagery Date: May 2015 Information shown is for general reference purposes only and does not necessarily represent exact geographic or cartographic data as mapped. The City of Auburn makes no warranty as to its accuracy. North Ridgeview Estates Plat Hearing Examiner Packet Page 33 of 422 -This page left intentionally blank- North Ridgeview Estates Plat Hearing Examiner Packet Page 34 of 422 EXHIBIT 3 LAND USE APPLICATION FORMS North Ridgeview Estates Plat Hearing Examiner Packet Page 35 of 422 -This page left intentionally blank- North Ridgeview Estates Plat Hearing Examiner Packet Page 36 of 422 North Ridgeview Estates PlatHearing Examiner Packet Page 37 of 422 North Ridgeview Preliminary Plat NARRATIVE January 12, 2017 Overview: A 30 lot subdivision on 29.7 acres within the R-1 zone with an Urban Separator Overlay. The lots will be served by public streets, water & sewer. The project will include 50% open space, a drainage facility, wetlands and a city required residential collector road. Pre-application meetings: Our first Pre-Application meeting for this project took place on May 6, 2015. Our second Pre-Application meeting took place August 31, 2016. Notes from both of these meetings are attached as part of our Preliminary Plat Submittal Package. Property: The property consists of three legal parcels all within the current City of Auburn limits. These parcels include 332205-9105 (6.88 acres), 332205-9115 (20.74 acres) and 3322059154 (2.07 acres) for a total of 29.69 acres or 1,293,315 square feet based on a Boundary & Topographic Survey conducted by Barghausen Consulting Engineers in May of 2016. These three parcels fall in the Urban Separator Overlay Zone. Existing Conditions: The site is located along the east side of 124th Ave SE and predominantly vacant except for three buildings, a vacant barn located completely on parcel 332205-9115, a dilapidated vacant mobile home on parcel 332205-9103, and a vacant barn on portions of 332205-9154 and 332205-9115. The predominant vegetation on the parcels is grasses and the majority of the tree coverage has been removed due to the years of agricultural use of the property. Surrounding Uses: The site is surrounded mostly by existing single family homes except for the southernmost part of the property which borders the Auburn Mountain View High School track and football field. The parcels also border the City of Kent’s water tower facility on parcel number 332205-9177. North Ridgeview Estates Plat Hearing Examiner Packet Page 38 of 422 North Ridgeview Estates PlatHearing Examiner Packet Page 39 of 422 Topography: The site is at its lowest elevations along Northwest and Northeast corners and rises to the south. The highest elevations are located in the southern portions of the property. The steepest slopes on site are in the 20% range therefore there are no “steep slope sensitive Areas”. The total elevation gain from the lowest point (392’) on site to the highest point(460’) on site is 68’. Access: The site includes approximately 1035 feet of frontage along 124th Ave. Our access point will come from 124th Ave SE just north of the current access at SE 286th Pl. There is currently an access/driveway at just south of this location at SE 286th Pl which serves the site, a church, and an existing City of Kent water tank on the adjacent parcel. The access to the Church and City of Kent Water Tower will be reconfigured to take access directly off of our proposed Road A. The current church and water tower driveway will be barricaded as to allow no further access off of 124th. We have entered into agreements with the Church and City of Kent to allow for the new access configuration. Zoning: The site is zoned R1 which allows residential densities of up to 1 unit per acre. These 3 parcels are in the Urban Separator Overlay which requires Lot Clustering. The maximum density for this 29.69 acres is 30 lots, as determined by City Staff during our first Pre-Application Meeting. The minimum lot size is 8,000 square feet and the minimum width is 35 feet per City of Auburn code 18.21.10 B. This acreage is based on a Boundary & Topographic Survey conducted by Barghausen Consulting Engineers in May of 2016. Please see attached survey. Proposed Use: We are proposing 30 single family residential lots with a minimum average width of 80+’ and a minimum depth of 115’, but not less than 8,000 square feet, all served off of a public road. This plat will include one drainage facility at the northwest corner (at the lowest elevation) and at least 50% open space per the Clustering requirement. We are providing over 50% Open Space. These open space tracts include three wetland tracts, and gently rolling grasslands. Roads: The site plan includes a public road – a residential collector (Road “A”) for access to the lots as well as two cul de sacs. This City of Auburn required residential collector road is proposed with a 55’ wide Right of Way and will include curbs, gutters, sidewalks and landscape strips per the City Road Standards. Although Road A is intended to meet the City requirement to ultimately connect to 132nd Ave SE (by others), the City has offered leniency in the design of the road so that the site can be served. North Ridgeview Estates Plat Hearing Examiner Packet Page 40 of 422 Wetlands: There are three wetlands located on the north portion of the sites. Please see the attached wetlands report prepared by Sewall Wetland Consulting, Inc. Open Space Requirement: The Urban Separator Overlay requires 50% open space, therefore we are required to provide 14.85 acres of open space. We are providing 15.54 acres of open space. This includes three wetland tracts as well as six open space tracts. Please see attached site plan. Storm Drainage: The proposed Detention and Water Quality Facility will be located in the northwest corner of the property since that is the lowest elevation of the property. The pond facility is proposed to discharge through two dispersal trenches via a flow splitter near the north property line. This will provide hydrology to the existing wetland system to the north. A typical enclosed system of conveyance pipes and catch basins will be included in the roadways. Soils: Soils testing was conducted by Earth Solutions Northwest and the soils consist predominantly of Glacial till and outwash deposits, therefore we expect some seasonal limitations for some construction activity, but there will be no other limitations for this proposed use. Please see attached soils report for more detail. Water: The proposed lots will be served by public water from Water District #111. Please see the attached Water Availability Certificate from Water District #111. Sewer: The proposed lots will be served by public sewer from Soos Creek Sewer District. Please see the attached Sewer Availability Certificate from Soos Creek Sewer District. Offsite easements have been obtained from the six affected homeowners who live on SE 285th St to the east of the site, which is where sewer will need to be extended from. These agreements have been recorded on title for each of the six homeowners. Schools: This project is unique in the fact that the homes will reside within the City of Auburn, but also lie within the Kent School District boundary. Currently the majority of the homes are within the Pine Tree Elementary School boundary with a smaller portion of the homes being within the Horizon Elementary School boundary. The same goes for Middle School with the majority attending Mattson Middle School with a smaller North Ridgeview Estates Plat Hearing Examiner Packet Page 41 of 422 portion falling within the Cedar Heights Middle School Boundary. The whole site is within the Kentlake High School Boundary. Please see our attached Schools Analysis Report. SEPA Application: Our SEPA Application will run concurrently with our Preliminary Plat Application. Please see attached SEPA Checklist. Variance Request: Our Variance Application will also run concurrently with our Preliminary Plat Application. We are formally requesting that front, side and backyard setbacks be adjusted from the R1 zone to the R5 zone setbacks, primarily based on the reduced lot sizes and extensive open space requirement. Please see attached Variance Request. Deviations/Deferral Requests: Our Deviation/Deferral Request will also run concurrently with our Preliminary Plat Application. We are requesting the following Deviations/Deferrals: 1. Cul de sac length 2. Secondary access requirement 3. Maximum number of homes on a dead end street 4. Minimum horizontal radii Please see attached list of enclosures and number of copies submitted. This concludes our summary. Jeff Potter Director of Land Development Integrity Land, LLC enc. North Ridgeview Estates Plat Hearing Examiner Packet Page 42 of 422 Enclosures: Preliminary Plat Copies Document 10 Application Form 1 Letter of Authorization 10 Concurrent Applications 1 Land Surveyor's Certificate 10 Legal Description 2 Title Report 10 Preliminary Subdivision Application Submittal Checklist 10 SEPA checklist 6 Traffic Impact Analysis 6 School Access Analysis 6 Preliminary Storm Report 6 Critical Areas Report 6 Soils Analysis Report 10 Sewer Availability 10 Water Availability 1 Pre-Application Meeting Notes 10 Site Distance 10 Preliminary Plat Drawing and Plans 10 Narrative 1 Digital Copy (CD) Variance Copies Document 10 Variance Application 10 Variance Concurrent Applications 10 Letter of Authorization 10 Written Statement 10 Site Plan 10 Vicinity Map 1 Digital Copy (CD) North Ridgeview Estates Plat Hearing Examiner Packet Page 43 of 422 North Ridgeview Estates PlatHearing Examiner Packet Page 44 of 422 -This page left intentionally blank- North Ridgeview Estates Plat Hearing Examiner Packet Page 45 of 422 North Ridgeview Estates PlatHearing Examiner Packet Page 46 of 422 EXHIBIT 4 SEPA DNS, NOTICE OF APPLICATION, AND NOTICE OF PUBLIC HEARING, SEPA CHECKLIST, AND NOTICING DOCUMENTS North Ridgeview Estates Plat Hearing Examiner Packet Page 47 of 422 -This page left intentionally blank- North Ridgeview Estates Plat Hearing Examiner Packet Page 48 of 422 NOTICE OF APPLICATION (NOA) NOTICE OF PUBLIC HEARING (NOH) and DETERMINATION OF NON-SIGNIFICANCE (DNS) North Ridgeview Estates 30-Lot Preliminary Plat SEP17-0001 / PLT17-0001 / VAR17-0002 The City of Auburn is issuing a Notice of Application (NOA), Notice of Public Hearing (NOH), and Determination of Non-Significance (DNS) for the following described project. The permit applications and listed studies may be reviewed at the Auburn Community Development & Public Works Department at 1 E Main St., 2nd Floor, Customer Service Center, Auburn, WA 98001. Proposal: Preliminary plat application to subdivide 29.7 acres into 30 single-family residential lots. The site is zoned R-1, Residential, which allows 1 lot per acre. The site is also located within the Urban Separator Overlay, which requires 50% of the site to be set aside as open space, and the lots to be clustered and maintain at least 8,000 sq. ft. of lot area; the proposed lots range in size from 10,115 sq. ft. to 21,490 sq. ft. with an average lot size of 13,235 sq. ft. A variance to the development standards for setbacks has also been requested to align with the proposed lot sizes, as opposed to the standard setbacks for 1 acre lots. A plat modification has also been requested from the clustering requirements of the Urban Separator Overlay. Location: The project site is located on the west side of 124th Ave. SE, approximately 600 ft. south of SE 282nd St., see Vicinity Map below. King Co. Parcel Nos. 332205-9103, 332205-9115, and 332205-9154. Notice of Application: December 8, 2017 Application Complete: February 8, 2017 Permit Application: January 12, 2017 File Nos. SEP17-0001 PLT17-0001 VAR17-0002 Applicant: Jeff Potter Auburn Ridgeview, LLC 27203 216th Ave, SE #5 Maple Valley, WA 98038 Property Owner: Same as Applicant Studies/Plans Submitted With Application: Preliminary Civil Plans Traffic Impact Analysis School Access Analysis Geotechnical Report Preliminary Stormwater Site Plan Critical Areas Report Preliminary Wetland and Buffer Mitigation Plans Other Permits, Plans, and Approvals Needed: Public Facility Extension (FAC) / Grading Permit(s) North Ridgeview Estates Plat Hearing Examiner Packet Page 49 of 422 NOTICE OF APPLICATION, NOTICE OF PUBLIC HEARING, and DETERMINATION OF NON-SIGNIFICANCE SEP17-0001 / PLT17-0001 / VAR17-0002 (Continued) Page 2 of 4 Statement of Consistency and List of Applicable Development Regulations: This proposal is subject to and shall be consistent with the Auburn City Code, Comprehensive Plan, and Public Works Design and Construction Standards. Lead Agency: City of Auburn The lead agency for this proposal has determined that it does not have probable significant adverse impact on the environment. An environmental impact statement (EIS) is not required under RCW 43.21C.030(2)(c). This decision was made after review of a completed environmental checklist and other information on file with the lead agency. This information is available to the public on request. Public Comment Period: This may be your only opportunity to comment on the environmental impact of the proposal. All persons may comment on this application. This DNS is issued under WAC 197-11-340(2); the lead agency will not act on this proposal for 15 days from the date issued below. Comments must be in writing and submitted by 5:00 p.m. on December 22, 2017 to the mailing address of 25 W Main St., Auburn, WA, 98001 or to the email address below. Any person wishing to become a party of record, shall include in their comments that they wish to receive notice of and participate in any hearings, if relevant, and request a copy of decisions once made. Any person aggrieved of the City's determination may file an appeal with the Auburn City Clerk at 25 West Main Street, Auburn, WA 98001- 4998 within 14 days of the close of the comment period, or by 5:00 p.m. on January 5, 2018. Public Hearing: The Hearing Examiner will conduct a public hearing on the Preliminary Plat and Variance in the City Council Chambers, 25 W. Main St., Auburn, WA, 98001, on January 18, 2018 at 5:30 p.m. Any interested person is invited to appear and express comments or opinions on the proposed project. Written comments may be emailed to the contact person below, mailed attention to the contact person below to 25 W. Main St., Auburn WA, 98001, or submitted at the public hearing. For citizens with speech, sight, or hearing disabilities wishing to review documents pertaining to this hearing should contact the person below within 10 calendar days prior to the hearing. Each request will be considered individually according to the type of request, the availability of resources, and the financial ability of the City to provide the requested services or equipment. For questions regarding this project, please contact Thaniel Gouk, Senior Planner, at tgouk@auburnwa.gov or 253-804-5031. RESPONSIBLE OFFICIAL: Jeff Tate POSITION/TITLE: Assistant Director, Community Dev. & Public Works Dept. ADDRESS: 25 West Main Street Auburn, Washington 98001 253-931-3090 DATE ISSUED: SIGNATURE: Note: This determination does not constitute approval of the proposal. Approval of the proposal can only be made by the legislative or administrative body vested with that authority. The proposal is required to meet all applicable regulations. [Signature on File] December 7, 2017 North Ridgeview Estates Plat Hearing Examiner Packet Page 50 of 422 NOTICE OF APPLICATION, NOTICE OF PUBLIC HEARING, and DETERMINATION OF NON-SIGNIFICANCE SEP17-0001 / PLT17-0001 / VAR17-0002 (Continued) Page 3 of 4 Vicinity Map North Ridgeview Estates Plat Hearing Examiner Packet Page 51 of 422 NOTICE OF APPLICATION, NOTICE OF PUBLIC HEARING, and DETERMINATION OF NON-SIGNIFICANCE SEP17-0001 / PLT17-0001 / VAR17-0002 (Continued) Page 4 of 4 Proposed Preliminary Plat Layout North Ridgeview Estates Plat Hearing Examiner Packet Page 52 of 422 North Ridgeview Estates PlatHearing Examiner Packet Page 53 of 422 Environmental Checklist (Continued) TO BE COMPLETED BY APPLICANT 2 12.Location of the proposal. Give sufficient information for a person to understand the precise location of your proposed project, including a street address, if any, and section, township, and range, if known. If a proposal would occur over a range of area, provide the range or boundaries of the site(s). Provide a legal description, site plan, vicinity map, and topographic map, if reasonably available. While you should submit any plans required by the agency, you are not required to duplicate maps or detailed plans submitted with any permit applications related to this checklist. ENVIRONMENTAL ELEMENTS 1.Earth A. General description of the site (circle one): Flat, rolling, hilly, steep slopes, mountainous, other. B. What is the steepest slope on the site (approximate percent slope)? C. What general types of soils are found on the site (for example, clay, sand, gravel, peat, muck)? If you know the classification of agricultural soils, specify them and note any prime farmland. D. Are there surface indications or history of unstable soils in the immediate vicinity? If so, describe. E. Describe the purpose, type, and approximate quantities of any filling or grading proposed. Indicate source of F. Could erosion occur as a result of clearing, construction, or use? If so, generally describe. G. About what percent of the site will be covered with impervious surfaces after project construction (for example, asphalt or buildings)? H. Proposed measures to reduce or control erosion, or other impacts to the earth. 2.Air A. What types of emissions to the air would result from the proposal (i.e., dust, automobile, odors, industrial wood smoke) during construction and when the project is completed? If any, generally describe and give approximate quantities if know. 124th Ave SE & SE 284th St Auburn, WA Parcels: 332205-9103 -9115, -9154 SE-33-22-5 Please see attached maps, site plan & vicinity map Use of BMP's during plat grading for streets, drainage facilities and lots. Also use of City required erosion control measures, including rip rap construction entrance, silt fencing, temporary ponds(as needed), berming and on site inspections & management. During plat construction there will be minimal emissions created from the use of construction equipment and associated dust as is typical for plat construction. Once plat is completed there are no atypical emissions to the air from the future residential uses. ____ The steepest slopes are in the 20% range. The soils on this site are primarily Glacial till and outwash deposits. Please see the attached Soils Report created by Earth Solutions Northwest. Due to the onsite stable soils & the use of BMP's, erosion is highly unlikely. Once the streets and drainage facilities are constructed and homes built, erosion will not occur, due to the use of an enclosed drainage system and landscaping. fill. Mass grading for the streets, drainage facility and lots is expected. We expect a possibility of 10,000 - 20,000 cy of imbalance on this project. We expect approximately 15-20% of the site will be impervious once the future homes are completed (under separate building permits). Please see attached response and Earth Solutions NW Supplemental Infiltration Evaluation and Reponse to City of Auburn Comments letter dated April 6, 2017. North Ridgeview Estates Plat Hearing Examiner Packet Page 54 of 422 North Ridgeview Estates PlatHearing Examiner Packet Page 55 of 422 North Ridgeview Estates PlatHearing Examiner Packet Page 56 of 422 North Ridgeview Estates PlatHearing Examiner Packet Page 57 of 422 North Ridgeview Estates PlatHearing Examiner Packet Page 58 of 422 North Ridgeview Estates PlatHearing Examiner Packet Page 59 of 422 North Ridgeview Estates PlatHearing Examiner Packet Page 60 of 422 North Ridgeview Estates PlatHearing Examiner Packet Page 61 of 422 North Ridgeview Estates PlatHearing Examiner Packet Page 62 of 422 FINAL STAFF EVALUATION FOR ENVIRONMENTAL CHECKLIST (SEP17-0001) Date: December 7, 2017 Project: Preliminary Plat of North Ridgeview Estates Applicant: Jeff Potter Auburn Ridgeview, LLC 27203 216th Ave, SE #5 Maple Valley, WA 98038 Property Owner Same as Applicant Location: West side of 124th Ave. SE, approximately 600 ft. south of SE 282nd St.. Parcel No. King Co. Parcel Nos. 332205-9103, 332205-9115, and 332205-9154. Parcel Size: 29.7 Acres Proposal: Preliminary plat application to subdivide 29.7 acres into 30 single-family residential lots. The site is zoned R-1, Residential, which allows 1 lot per acre. The site is also located within the Urban Separator Overlay, which requires 50% of the site to be set aside as open space, and the lots to be clustered and maintain at least 8,000 sq. ft. of lot area; the proposed lots range in size from 10,115 sq. ft. to 21,490 sq. ft. with an average lot size of 13,235 sq. ft. A variance to the development standards for setbacks has also been requested to align with the proposed lot sizes, as opposed to the standard setbacks for 1 acre lots. A plat modification has also been requested from the clustering requirements of the Urban Separator Overlay. Existing Zoning: R-1 with Urban Separator Overlay Existing Comprehensive Plan Designation: Single Family A.BACKGROUND: Pursuant to WAC 197-11-340(2), the City of Auburn is required to send any Determination of Non-Significance (DNS) which may result from this environmental review, along with the checklist, to the Washington State Department of Ecology (DOE), U.S. Army Corps of Engineers, or other agencies with jurisdiction, affected tribes, and interested parties. Therefore, the City will not act on this proposal for fifteen days after the issuance of the DNS. North Ridgeview Estates Plat Hearing Examiner Packet Page 63 of 422 Final Staff Evaluation for Environmental Checklist – SEP17-0001 (Continued) Page 2 of 4 8. Other Environmental Information: Other environmental information prepared or will be prepared directly related to this proposal includes:  Preliminary Civil Plans  Traffic Impact Analysis  School Access Analysis  Geotechnical Report  Preliminary Stormwater Site Plan  Critical Areas Report  Preliminary Wetland and Buffer Mitigation Plans 10. Other Approvals/Permits Needed:  Public Facility Extension (FAC) / Grading Permit(s) B. ENVIRONMENTAL ELEMENTS: 1. Earth: Concur with checklist. The northern half of the project site slopes down to the north with 20% slopes in some areas. The southern, uphill, portion of the site gently slopes from the south to north with slopes ranging from approximately 2% to 10%. Mass grading will be required to construct the required residential collector through the site and the proposed lots on the north side of the street. 2. Air: Concur with checklist. Short term impacts on air quality, such as an increase in local suspended particulate levels, would occur during construction activity associated with the project. To minimize short term impacts to air quality, contract specifications will require the development and implementation of dust and emission control measures such as watering and sweeping and turning off equipment and vehicles when not in use, as consistent with the City’s Construction Standards. 3. Water: A. Surface: Concur with checklist. There are three wetlands in the northern portion of the site. Stormwater from the development has been studied and will ensure the vitality of the wetlands remains. In addition, buffer enhancements will be required with the development. A stream known as “Westside Soos Creek” is located off-site to the north. B. Ground: Concur with checklist. Stormwater will be managed on-site, consistent with applicable state and local standards. Areas of the site have been identified as having seepage; the Geotechnical Report identifies these areas and provides the requirements for development. C. Runoff/Storm water: Concur with checklist. North Ridgeview Estates Plat Hearing Examiner Packet Page 64 of 422 Final Staff Evaluation for Environmental Checklist – SEP17-0001 (Continued) Page 3 of 4 Stormwater will be managed on-site, consistent with applicable state and local standards. The project is located within Ground Water Protection Zone 4 and will be subject to ACC 16.10.120(E)(2). D. Proposed Measures to Reduce or Control Surface, Ground, and Runoff Water Impacts: Concur with checklist. Best Management Practices (BMPs) will be employed during and after construction to control any impacts to ground/surface/storm water. 3. Plants: Concur with checklist. No threatened or endangered species are known to be on or near the site. There are several trees on the site that will try to be retained, however, may need to be removed depending on final grading plans. The development is required to set aside 50% of the site as open space which will retain some native vegetation, a buffer enhancement plan for the wetlands will be implemented, and the stormwater tract will provide plantings. 6. Animals: Concur with checklist. Also, to note, there is a stream to the north with mapped priority habitat around it. 7. Energy and Natural Resources: Concur with checklist. Impacts to energy and natural resources will be consistent with what is expected for a typical residential subdivision. The homes will comply with applicable building and energy codes. 8. Environmental Health: Concur with checklist. No environmental health hazards above normal construction activities are expected and risk reduction measures consistent with the City’s Construction Standards will be implemented and followed. 9. Noise: Concur with checklist. 10. Land and Shoreline Use: Concur with checklist. The site is zoned R-1 with an Urban Separator Overlay which requires 50% of the site to be set aside as open space. 11. Housing: Concur with checklist. 12. Aesthetics: Concur with checklist. 13. Light and Glare: Concur with checklist. Lighting typical of a typical single-family neighborhood is expected. Street lighting will also be provided including some additional lighting at the intersection of the new residential collector with 124th Ave. SE to compensate for reduced sight distance. 14. Recreation: Concur with checklist. North Ridgeview Estates Plat Hearing Examiner Packet Page 65 of 422 Final Staff Evaluation for Environmental Checklist – SEP17-0001 (Continued) Page 4 of 4 The dedication of park land is not triggered with the proposed development; park impact fees will be paid for each residential unit upon building permit issuance. Passive recreation area will be provided for throughout the plat with the preserved open space. 15.Historic and Cultural Preservation: Concur with checklist. No historic or culturally sensitive places or objects are present on the site, nor would any be affected by this project. 16.Transportation: Concur with checklist. A new residential collector will be constructed to extend through the site from 124th Ave. SE and will eventually connect to 132nd Ave SE, to the east. Transit is available within 1.1 miles. of the site. Traffic impact fees will be paid for each residential unit upon building permit issuance. 17.Public Services: Concur with checklist. 18.Utilities: Concur with checklist. All necessary utilities will be provided to the project site. The off-site water main extension (Water District #111) has already been completed stubbing the main to the eastern perimeter of the site from 132nd Ave. SE. along SE 285th St. C.CONCLUSIONS: The proposal can be found to not have a probable significant adverse impact on the environment. The City reserves the right to review any future revision or alterations to the site or to the proposal in order to determine the environmental significance or non-significance of the project at that point in time. Prepared by: Thaniel Gouk, Senior Planner, Community Development and Public Works Department, City of Auburn North Ridgeview Estates Plat Hearing Examiner Packet Page 66 of 422 1 Thaniel Gouk From:Thaniel Gouk Sent:Thursday, December 7, 2017 12:43 PM To:'gretchen.kaehler@dahp.wa.gov'; 'RalphM@pscleanair.org'; 'James.H.Carsner@usace.army.mil'; 'Larry.Fisher@dfw.wa.gov'; 'maint.roads@kingcounty.gov'; 'Karen.walter@muckleshoot.nsn.us'; 'pazookR@wsdot.wa.gov'; 'Gary.Kriedt@kingcounty.gov'; 'sepacenter@dnr.wa.gov'; 'paan461@ecy.wa.gov'; 'sepaunit@ecy.wa.gov'; 'laura.murphy@muckleshoot.nsn.us'; 'Grant.Timentwa@muckleshoot.nsn.us'; 'dhoffman@mbaks.com'; 'mindy@wecprotects.org'; 'rob.ryan@wa.usda.gov'; 'shirlee.tan@kingcounty.gov'; 'cblansfield@auburn.wednet.edu'; 'tim@futurewise.org'; 'Steve.Bleifuhs@kingcounty.gov'; 'josh.baldi@kingcounty.gov'; 'randy.sandin@kingcounty.gov'; 'Valerie.Garza@kingcounty.gov'; 'laila.mcclinton@kingcounty.gov'; 'jeff.payne@pse.com'; 'canderson@kentwa.gov'; 'Ralph.Fortunato@kent.K12.WA.US'; 'perry.weinberg@soundtransit.org'; 'greed@kentwa.gov'; 'mgagliardo@cascadewater.org'; 'customerservice@wd111.com'; 'rspeer@sooscreek.com'; 'Rybolt.S@portseattle.org' Cc:Steven Sturza Subject:SEP17-0001 - North Ridgeview Estates Preliminary Plat (PLT17-0001, VAR17-0002) Attachments:SEP17-0001 PLT17-0001 VAR17-0002 NOA_NOH_DNS.PDF; PLT17-0001 SEP17-0001 SEPA Checklist 09192017.pdf; PLT17-0001 SEP17-0001 SEPA Checklist Geotch Supp 04062017.pdf Please see the attached SEPA DNS and Notice of Application for a proposed 30-Lot preliminary plat. Contact me if you have any questions. Thanks, Thaniel Gouk | Senior Planner 253-804-5031 North Ridgeview Estates Plat Hearing Examiner Packet Page 67 of 422 SEP17-0001 PLT17-0001 VAR17-0002 Mailing ListOWNER NAME OWNER ADDRESS2 OWNER ADDRESS OWNER CITY OWNER STATE OWNER ZIPCODE KENT SCHOOL DISTRICT 12033 SE 256TH ST KENT WA 98031 MOHAZZABFAR ESKANDAR 12040 98TH AVE NE STE #201 KIRKLAND WA 98034 GILL PARMINDER K 12206 SE 307TH PL AUBURN WA 98092 RIEMER DIETRICH E RIEMER ROSEMARIE R 12221 SE 284TH ST AUBURN WA 98092 LAUDERMILK STEVEN P 12411 SE 282ND ST AUBURN WA 98092 YERXA RILEY W+MARY E 12412 SE 288TH PL AUBURN WA 98002 CALDIERA JOYCE 12422 SE 288TH PL AUBURN WA 98092 CREVELING DANIEL & KELLY 12423 SE 288TH PL AUBURN WA 98092 COX TRAVIS J AND BONNI E 12430 SE 288TH PL AUBURN WA 98092 SACHA MARG LLC 12431 SE 286TH PL AUBURN WA 98092 GASTON RICKY L 12431 SE 288TH PL AUBURN WA 98002 LEWIS JOHN C+SUSAN J 12440 SE 288TH PL AUBURN WA 98092 LOWE VAN A & CHARMAYNE 12441 SE 288TH PL AUBURN WA 98092 HUGHES GLADYS 12450 SE 288TH PL AUBURN WA 98092 YOUNG JOSHUA D+VANESSA J 12458 SE 288TH PL AUBURN WA 98092 CARRANZA JUAN M+BERENICE AR 12459 SE 288TH PL AUBURN WA 98092 DHALIWAL GURDEV S+RAJINDER 12578 WELLS PLACE SURREY BC V3V 6N4 ENGELHARDT ARNOLD E 12623 SE 282ND ST AUBURN WA 98092 CEDERWALL PAUL D+DEBBIE L 12818 SE 285TH ST KENT WA 98031 DAKAN PETER B+CAROL S 12821 SE 285TH ST AUBURN WA 98092 DULANEY ALLISON+TIMOTHY SUL 12903 SE 285TH ST AUBURN WA 98092 MUSKELLY THURSTON E+CHERYL 12931 SE 288TH PL AUBURN WA 98092 KIM KI J+OKJOO 12932 SE 288TH PL AUBURN WA 98092 WENDT MICHAEL R+KEISHA 12937 SE 288TH PL AUBURN WA 98092 GUILD JEFFERY R 12938 SE 288TH PL AUBURN WA 98092 JOSEPH REENA 12944 SE 288TH PL AUBURN WA 98092 BURROWS TIMOTHY S+ANDREA J 12950 SE 288TH PL AUBURN WA 98092 BANKS GERALD L 211 L ST SE AUBURN WA 98002 KENT CITY OF 220 4TH AVE S KENT WA 98032 WILLIAMS THOMAS L+MARY A 28624 124TH AVE SE KENT WA 98031 SOIKE KIRBY L 28706 124TH AVE SE AUBURN WA 98092 HORN PATRICIA R 28718 124TH SE AUBURN WA 98092 COLLA BARBARA ANN 3700 CALIFORNIA AVE SW #7 SEATTLE WA 98116 WEN LIMIN 5210 NE 8TH PL RENTON WA 98059 AUBURN SCHOOL DIST #408 915 4TH ST NE AUBURN WA 98002 BLECHEN EDGAR M+LAURA A PO BOX 50492 BELLEVUE WA 98015 North Ridgeview Estates Plat Hearing Examiner Packet Page 68 of 422 EXHIBIT 5 WRITTEN COMMENTS RECEIVED North Ridgeview Estates Plat Hearing Examiner Packet Page 69 of 422 -This page left intentionally blank- North Ridgeview Estates Plat Hearing Examiner Packet Page 70 of 422 1 Thaniel Gouk From:Karen Walter <KWalter@muckleshoot.nsn.us> Sent:Wednesday, December 20, 2017 6:27 PM To:Thaniel Gouk Subject:RE: SEP17-0001 - North Ridgeview Estates Preliminary Plat (PLT17-0001, VAR17-0002) Attachments:coho spawn mortality western US urban watersheds_bioinfiltration prevents lethal stormwater impacts_2016.pdf; Landscape Ecotoxicology of Coho Salmon Spawner Mortality in Urban watersheds.pdf Thaniel, Thank you again for sending the link to the requested documents for the proposed North Ridgeview Estates Plat referenced above. We have reviewed this information and offer the following comments in the interest of protecting and restoring the Tribe’s treaty-protected fisheries resources: Stormwater treatment The project is proposing to use “basic” treatment methods to treat stormwater from this project which will discharge into wetlands that are connected to the Westside Soos Creek stream, a tributary to Soos Creek. King County’s IMAP for this stream indicates that it is a Class 2 stream with salmonids. The stream flows into Soosette Creek, a known-salmon bearing stream in the Soos Creek watershed. The Soos Creek watershed is important in supporting the Tribe’s fisheries. As such, treated stormwater discharged from this project has the potential to adversely affect salmon, particularly coho salmon, due to metals and oils commonly found in stormwater (see attachments). Therefore, the project should modified its treatment approach and provide “enhanced” treatment of stormwater generated from this project to reduce oils and metals in stormwater. We appreciate the opportunity to review this proposal and look forward to the City/applicants’ responses to these concerns. Please let me know if you have any questions. Best regards, Karen Walter Watersheds and Land Use Team Leader Muckleshoot Indian Tribe Fisheries Division Habitat Program Phillip Starr Building 39015-A 172nd Ave SE Auburn, WA 98092 253-876-3116 From: Thaniel Gouk [mailto:tgouk@auburnwa.gov] Sent: Thursday, December 07, 2017 12:43 PM To: 'gretchen.kaehler@dahp.wa.gov'; 'RalphM@pscleanair.org'; 'James.H.Carsner@usace.army.mil'; 'Larry.Fisher@dfw.wa.gov'; 'maint.roads@kingcounty.gov'; Karen Walter; 'pazookR@wsdot.wa.gov'; 'Gary.Kriedt@kingcounty.gov'; 'sepacenter@dnr.wa.gov'; 'paan461@ecy.wa.gov'; 'sepaunit@ecy.wa.gov'; Laura Murphy; Grant Timentwa; 'dhoffman@mbaks.com'; 'mindy@wecprotects.org'; 'rob.ryan@wa.usda.gov'; 'shirlee.tan@kingcounty.gov'; 'cblansfield@auburn.wednet.edu'; 'tim@futurewise.org'; 'Steve.Bleifuhs@kingcounty.gov'; 'josh.baldi@kingcounty.gov'; 'randy.sandin@kingcounty.gov'; 'Valerie.Garza@kingcounty.gov'; 'laila.mcclinton@kingcounty.gov'; 'jeff.payne@pse.com'; 'canderson@kentwa.gov'; 'Ralph.Fortunato@kent.K12.WA.US'; 'perry.weinberg@soundtransit.org'; 'greed@kentwa.gov'; 'mgagliardo@cascadewater.org'; 'customerservice@wd111.com'; 'rspeer@sooscreek.com'; 'Rybolt.S@portseattle.org' Cc: Steven Sturza Subject: SEP17-0001 - North Ridgeview Estates Preliminary Plat (PLT17-0001, VAR17-0002) Please see the attached SEPA DNS and Notice of Application for a proposed 30-Lot preliminary plat. North Ridgeview Estates Plat Hearing Examiner Packet Page 71 of 422 2 Contact me if you have any questions. Thanks, Thaniel Gouk | Senior Planner 253-804-5031 The information contained in this electronic communication is personal, privileged and/or confidential information intended only for the use of the individual(s) or entity(ies) to which it has been addressed. If you read this communication and are not the intended recipient, you are hereby notified that any dissemination, distribution or copying of this communication, other than delivery to the intend ed recipient is strictly prohibited. If you have received this communication in error, please immediately notify the sender by reply e-mail. Thank you. North Ridgeview Estates Plat Hearing Examiner Packet Page 72 of 422 Coho salmon spawner mortality in western US urban watersheds: bioinfiltration prevents lethal storm water impacts Julann A. Spromberg 1, David H. Baldwin 2, Steven E. Damm 3, Jenifer K. McIntyre 4, Michael Huff 5, Catherine A. Sloan 2, Bernadita F. Anulacion 2, Jay W. Davis 3 and Nathaniel L. Scholz 2* 1Ocean Associates, Under Contract to Northwest Fisheries Science Center, National Marine Fisheries Service, NOAA, 2725 Montlake Blvd. E., Seattle, WA 98112, USA; 2Environmental and Fisheries Science Division, Northwest Fisheries Science Center, National Marine Fisheries Service, NOAA, 2725 Montlake Blvd. E., Seattle, WA 98112, USA;3U.S. Fish and Wildlife Service, Washington Fish and Wildlife Office, 510 Desmond Dr. S.E., Lacey, WA 98503, USA;4Puyallup Research and Extension Center, Washington State University, 2606 W. Pioneer Ave., Puyallup, WA 98371, USA; and 5Suquamish Tribe, PO Box 498, 18490, Suquamish Way, Suquamish, WA 98392, USA Summary 1.Adult coho salmon Oncorhynchus kisutch return each autumn to freshwater spawning habitats throughout western North America. The migration coincides with increasing seasonal rainfall, which in turn increases storm water run-off, particularly in urban watersheds with extensive impervious land cover. Previous field assessments in urban stream networks have shown that adult coho are dying prematurely at high rates (>50%). Despite significant man- agement concerns for the long-term conservation of threatened wild coho populations, a cau- sal role for toxic run-off in the mortality syndrome has not been demonstrated. 2.We exposed otherwise healthy coho spawners to: (i) artificial storm water containing mix- tures of metals and petroleum hydrocarbons, at or above concentrations previously measured in urban run-off; (ii) undiluted storm water collected from a high traffic volume urban arterial road (i.e. highway run-off); and (iii) highway run-off that was first pre-treated via bioinfiltra- tion through experimental soil columns to remove pollutants. 3.We find that mixtures of metals and petroleum hydrocarbons –conventional toxic con- stituents in urban storm water –are not sufficient to cause the spawner mortality syndrome. By contrast, untreated highway run-off collected during nine distinct storm events was univer- sally lethal to adult coho relative to unexposed controls. Lastly, the mortality syndrome was prevented when highway run-off was pretreated by soil infiltration, a conventional green storm water infrastructure technology. 4.Our results are the first direct evidence that: (i) toxic run-off is killing adult coho in urban watersheds, and (ii) inexpensive mitigation measures can improve water quality and promote salmon survival. 5.Synthesis and applications. Coho salmon, an iconic species with exceptional economic and cultural significance, are an ecological sentinel for the harmful effects of untreated urban run- off. Wild coho populations cannot withstand the high rates of mortality that are now regularly occurring in urban spawning habitats. Green storm water infrastructure or similar pollution prevention methods should be incorporated to the maximal extent practicable, at the watershed scale, for all future development and redevelopment projects, particularly those involving transportation infrastructure. Key-words:habitat restoration, non-point source pollution, Pacific salmon, run-off, storm water, urban ecology, urban streams *Correspondence author. E-mail: nathaniel.scholz@noaa.gov ©2015 The Authors. Journal of Applied Ecology ©2015 British Ecological Society. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. Journal of Applied Ecology 2016,53,398–407 doi: 10.1111/1365-2664.12534 North Ridgeview Estates Plat Hearing Examiner Packet Page 73 of 422 Introduction In recent decades, non-point source run-off has become the leading pollution threat to aquatic habitats in the USA and similarly developed countries. In highly built watersheds, the transport of toxic chemical contaminants via storm water contributes to the well documented ‘urban stream syndrome’, as evidenced by various indica- tors of biological and ecological degradation (Walsh et al. 2005). These include declines in species abundance, species diversity and the proliferation of non-native, pollution- tolerant taxa. Nevertheless, field assessments in urban watersheds rarely report fish kills or similar acute mortality events for aquatic life. A notable exception is the recurring die-off of adult coho salmon that return from the ocean to spawn each year in large metropolitan areas of northern Califor- nia, western Oregon and Washington in the USA, and southern British Columbia in Canada. The coho mortality phenomenon has been studied most extensively in lowland streams of the greater Seattle area of Puget Sound. Coho begin the freshwater phase of their spawning migration with the onset of autumn rainfall. Typically within days of arriving at stream reaches suitable for spawning, affected fish become stricken with symptoms that progress from a loss of orientation (surface swimming) to a loss of equilibrium and death on a time-scale of a few hours (Videos S1 and S2, Supporting information; Scholz et al. 2011). Year-to-year mortality rates within and across urban watersheds are typically high (~50–90%), as mea- sured by the proportion of unspawned females for an entire annual run (Scholz et al.2011). As might be expected, initial modelling indicates that such high mortality rates at the critical spawner life stages pose a significant extinction risk for wild coho populations (Spromberg & Scholz 2011). Coho distinct population seg- ments, or evolutionarily significant units (ESUs; Waples 1991), are comprised of metapopulations that span large river basins with varying degrees of urban and suburban land use (e.g. Pess et al.2002; Bilby & Mollot 2008). This population structure and the highly migratory life histories of salmonids have generally constrained ecotoxicological studies (Ross et al.2013). Nevertheless, if urban run-off is killing adult coho, ongoing regional development pressures may present an important obstacle to the recovery of coho ESUs, including those designated as threated (Lower Columbia River) or a species of concern (Puget Sound) under the US Endangered Species Act. To date, the evidence linking urban storm water run-off and coho spawner mortality has been indirect. The uni- form nature of the symptoms, over many years and across many streams, is consistent with a common and prevalent form of toxicity. A forensic investigation spanning nearly a decade ruled out several other potential causes, includ- ing conventional water quality parameters (e.g. dissolved oxygen, temperature), habitat availability, poor spawner condition and disease (Scholz et al.2011). Moreover, an initial geospatial land cover analysis found a significant positive association between the severity of the coho die- off phenomenon and the extent of impervious surface within a watershed (Feist et al.2011). The aim of the present study was to explore the connec- tion between water quality and coho mortality more directly by experimentally exposing freshwater-phase spawners to both artificial and actual highway run-off. Although urban storm water is chemically complex, field collected samples consistently contain motor vehicle- derived mixtures of metals and polycyclic aromatic hydro- carbons (PAHs), many of which are toxic to salmon at other life stages (e.g. copper, McIntyre et al.2012; Sandahl et al.2007; PAHs, Meador et al.2006; Heintz et al.2000). If the mortality syndrome could be repro- duced with an environmentally realistic mixture of metals and PAHs, it would then be possible to identify the causal agents by removing different components of the mixture. To account for the possibility that some other contami- nant(s) may be causal, we also exposed adult coho to storm water collected from a dense urban arterial road (i.e. highway run-off). Lastly, we exposed adult coho to highway run-off which was pre-treated with a conven- tional green storm water infrastructure (GSI) technology (bioinfiltration through soil columns) to remove pollu- tants, with the aim of lessening or eliminating any overtly harmful impacts of unmitigated storm water. Materials and methods ANIMALS Adult coho salmon were collected at the Suquamish Tribe’s Gro- vers Creek Hatchery near Poulsbo, Washington. Hatchery coho are an appropriate surrogate for wild coho given that field obser- vations have documented the mortality syndrome in spawners of both wild and hatchery origins (Scholz et al.2011). At Grovers Creek, returning coho migrate <4 km in freshwater from Miller Bay in Puget Sound to a hatchery pond via a fish ladder. The pond was seined on Monday, Wednesday and Friday of each week, and thus the fish were in the pond for a maximum of 72 h prior to capture. The coho were strays from a net-pen operation designed to provide a terminal fishery to the south of Miller Bay. When available, females were used for the controlled storm water exposures. For trials with an insufficient number of females, males were also included, as the urban mortality syndrome affects males and females alike (Scholz et al.2011). Only fish exhibiting normal behaviour and with no obvious signs of trauma, disease or poor condition were included. One set of exposures was con- ducted on a given day. Each individual coho spawner was placed in a holding tube con- structed of PVC, of either 15 2 9 76 2 cm (diameter 9 length) or 20 3 9 106 7 cm with 1 1-cm-thick polyethylene gates fitted into slots at either end. Ventilation was provided by six 2 5-cm-diameter holes on either side of the anterior (head) end of each tube and five 1 75-cm-diameter holes in each gate. A ventilation hose attached to a pump (for 2011–12, a Flotec Tempest 1/6 HP, 4 5m3 h 1 (Flotec Water, Delavan, WI, USA); for 2013–14, a Lifegard Aquatics Quiet One 3000, 3 1m3 h 1 (Lifegard Aquatics, Cerritos, CA, ©2015 The Authors. Journal of Applied Ecology ©2015 British Ecological Society,Journal of Applied Ecology,53, 398–407 Toxic urban run-off and salmon survival 399 North Ridgeview Estates Plat Hearing Examiner Packet Page 74 of 422 USA)) submerged in the polyethylene tank supplied a minimum of 4 L min 1 flow through the forward gate and over each fish in an anterior–posterior direction. For each trial, four separate coho holding tubes were placed in a large polyethylene tank containing 440 L of clean well water, artificial storm water, highway run-off, or run-off pretreated with soil infiltration. Adult coho were exposed for 4–48 h depending on the treatment (see below). Aeration was provided with air stones attached to an air pump (Coralife 05146 Model SL-38 Super Luft Air Pump, Central Aquatics-Coralife, Franklin, WI, USA). Exposure waters were maintained at temperatures below 14 °C by flow-through (2011) and Aqua Logic Cyclone Drop- In Titanium Chillers (2012). Smaller ventilation pumps that pro- duced less heat were used in 2013–14, and thus, chillers were not needed. EXPOSURES TO ARTIFICIAL STORM WATER In the autumn of 2011, returning adult coho were exposed to artificial storm water containing mixtures of PAHs and metals. The mixtures were comprised of individual compounds at concen- trations at or above those measured during autumn storm events in Seattle-area urban streams (Seattle Public Utilities 2007), or at levels representative of urban storm water run-off more generally (Stein, Tiefenthaler & Schiff 2006; Gobel, Dierkes & Coldewey 2007; Tiefenthaler, Stein & Schiff 2008). The PAH profile of urban run-off is compositionally similar to that of crude oil, par- ticularly for toxic three- and four-ring compounds (McIntyre et al.2014). The exception is a lack of dissolved pyrene and fluo- ranthene in crude oil (Incardona et al.2009). Thus, the PAH por- tion of the mixture was generated from a water-accommodated fraction (WAF) of Alaska North Slope crude oil, to which pyro- genic pyrene and fluoranthene were added (Table S1). The WAFs were prepared in a 3-speed commercial blender with a 3 8-L stainless steel container (Waring CB15; Waring Commercial, Tor- rington, CT, USA), following a protocol developed to yield fine oil droplets and bioavailable PAHs in the dissolved phase (Incardona et al.2013). In brief, the stainless steel container was cleaned with acetone and dichloromethane, the rubber lid was lined with dichloromethane-rinsed heavy-duty aluminium foil, and the container was filled with 1 L of deionized water. The vol- ume of crude oil added to the WAF (1 mL) was intended to pro- duce a final maximum phenanthrene exposure concentration of 0 384 lgL 1 (Stein, Tiefenthaler & Schiff 2006). Pyrene and fluo- ranthene were then added to coequal final target exposure con- centrations of 0 584 lgL 1. Water and oil were blended for 30 s on the lowest speed four times. The oil–water mixture was then poured into a 1-L separatory funnel and allowed to sit for 1 h. With care to leave the surface slick undisturbed, 789 3 mL at the bottom were then drawn off and added to the exposure chamber. The metals fraction of the PAHs/metals mixture consisted of cadmium, nickel, lead, copper and zinc (anhydrous CdCl2, NiCl2, PbCl2,CuCl2 and ZnCl2; Sigma-Aldrich, St. Louis, MO, USA, >98% purity) added to clean well water at nominal concentra- tions (Table S1) that were in the upper range of metal detections in urban streams (Stein, Tiefenthaler & Schiff 2006; Gobel, Dierkes & Coldewey 2007; Seattle Public Utilities 2007; Tiefen- thaler, Stein & Schiff 2008). Moreover, the concentrations of met- als in urban run-off are transiently elevated during the first flush interval (Kayhanian et al.2012). To capture this exposure scenar- io, experiments in the autumn of 2012 used relatively higher nominal concentrations of metals only (Table S1). Temperature and dissolved oxygen were monitored and maintained at physio- logical ranges for adult salmon, and water samples were collected for analytical verification of exposure concentrations. EXPOSURES TO HIGHWAY RUN-OFF Storm water was collected from the downspouts of an elevated urban principal arterial road in Seattle, WA. The downspouts receive run-off from the on-ramp to a four-lane (70 m wide) highway over which approximately 60 000 motor vehicles travel each day (WA DOT 2013a). The highway, paved with Portland cement concrete (WA DOT 2013b), is a conventional urban impervious surface. All of the flow to the downspouts originated from precipitation falling on the active arterial road. The captured run-off was transported to the hatchery facility in either covered glass carboys or in a stainless steel tank. The holding interval prior to exposures varied with the timing and intensity of autumn storm events, but did not exceed 72 h. While some collec- tions took place after an extended antecedent dry interval and therefore included the first flush for a given storm, others spanned periods of intermittent rainfall. Daily and cumulative rainfall for each autumn season is shown in Fig. 1, with each storm water col- lection interval superimposed (solid rectangular boxes). Collected run-off was used for one exposure only. Temperature, pH and dis- solved oxygen were measured at the outset of each exposure, and water samples were collected for chemical analyses to quantify con- centrations of metals and PAHs (2012–13 but not 2014 storms). After exposures, the run-off was transported to a Kitsap County Wastewater Pump Station for disposal. EXPOSURES TO FILTERED RUN-OFF In the autumn of 2013, four 200-L bioretention columns were con- structed and plumbed with outflow drains following conventional guidelines for green storm water infrastructure (WA DOE 2012). The filtration columns were composed of a 30 5-cm drainage layer of gravel aggregate overlain by 61 cm of bioretention soil media (60% sand: 40% compost) and topped with 5 cm of mulched bark. In the autumn of 2014, the bioretention columns were emptied and fresh media installed. In each year, the bioretention media were conditioned by passing seven pore volumes (660 L) of clean well water from the hatchery facility through each column at a rate of 2 L min 1: equivalent to 2 months of summer rainfall on a con- tributing area 20 times the size of the treatment area. Urban high- way run-off was collected as described above, and the homogenized volume was evenly divided to flow through one of the four bioretention columns at a rate of 2 L min 1, with the out- flows from the four columns recombined into a single post-treat- ment exposure volume. Adult coho spawners were exposed to either untreated urban storm water or the same run-off post- filtration for 4–24 h. Water quality was measured, and samples were collected for chemical analyses as described above. OBSERVATIONS OF SYMPTOMATIC FISH Hallmark characteristics of the adult coho spawner mortality syn- drome include a progression from lethargy to a loss of orienta- tion, a loss of equilibrium, followed by death (Scholz et al.2011). Individual fish were examined for these symptoms during and after each exposure. Fish were moved from the large exposure ©2015 The Authors. Journal of Applied Ecology ©2015 British Ecological Society,Journal of Applied Ecology,53, 398–407 400 J. A. Spromberg et al. North Ridgeview Estates Plat Hearing Examiner Packet Page 75 of 422 tank and released from their holding tubes into an observation tank containing clean well water at a minimum depth of 50 cm. Swimming ability and evasiveness (responses to light and gentle prodding) were recorded over a 1- to 3-min observation interval. For the trials using artificial storm water, symptomology was assessed at 24 h and then again at the end of the exposure. Coho exposed to highway run-off were visually examined at 2, 4 and 24 h. Live fish at 2 and 4 h were returned to their holding tubes and exposure chambers for the remainder of the trial. WATER QUALITY ANALYSES Conventional water quality parameters, including pH, dissolved oxygen, alkalinity, total suspended solids, N-ammonia, nutrients and organic carbon, were measured for selected trails using stan- dard instrumentation or by outside laboratories using US EPA- approved methods (Analytical Resources Inc., Tukwila, WA, USA or Am Test Inc., Kirkland, WA, USA). Total and dissolved concentrations of cadmium, copper, nickel, lead and zinc were determined by inductively coupled plasma mass spectrometry (ICP-MS) by Frontier Global Sciences (Bothell, WA, USA; EPA method 1638) or Am Test Inc. (EPA method 200.8). Briefly, sam- ples were preserved in 1% (v/v) nitric acid (total metals) or passed through a 0 45-lm filter (dissolved metals) and then oven- digested prior to analysis by ICP-MS. Duplicate samples and lab- oratory blanks were included to ensure quality control. Selected water samples for PAH determinations were preserved with 10% dichloromethane and stored at 4 °C in amber glass bottles until analysis at the NOAA Northwest Fisheries Science Center by gas chromatography/mass spectrometry (GC-MS) with additional selected ion monitoring for alkyl-PAHs (Sloan et al.2014). TISSUE SAMPLING AND ANALYSES At the conclusion of each exposure, fish length, weight, reproduc- tive status and origin (i.e. hatchery or wild spawned) were assessed. To confirm the bioavailability of PAHs in exposure waters, bile was screened for PAH metabolites in a subset of 2011 and 2012 trials with both artificial storm water and highway run-off. Fish were killed, and bile was collected from the gall bladder and stored in amber glass vials at 20 °C until analysis for PAH metabolites using high-performance liquid chromatogra- phy with fluorescence detection (Krahn et al.1986; da Silva et al. 2006). The concentrations of fluorescent PAH metabolites in bile are determined using naphthalene (NPH), phenanthrene (PHN) and benzo[a]pyrene (BaP) as external standards and converting the relative fluorescence response of bile to NPH, PHN and BaP equivalents, and reported as ng g 1 bile or ng mg 1 biliary pro- tein. Coho gills were sampled to confirm uptake of metals in selected 2011 and 2012 artificial and collected storm water exposures. Tis- sues were excised with Teflon or titanium scissors and plastic for- ceps, placed in plastic Whirl-paks, and stored at 80 °C. Metals analyses were determined by inductively coupled mass spec- troscopy (ICP-MS) at the Trace Elements Research Laboratory (TERL; College Station, TX, USA) using standard methods (TERL Method Codes 001, 006). Briefly, gill tissues were wet digested with nitric acid, freeze-dried, and homogenized by ball- milling in plastic containers. Samples were ionized in high- temperature argon plasma, and positively charged ions were sepa- rated on the basis of their mass : charge ratios by a quadrupole mass spectrometer. Student’s t-tests assessed differences in the tis- sue concentrations between exposures and their respective paired control. Results ADULT COHO RESPONSES ACROSS TREATMENTS Coho spawners exposed for 24 h to mixtures of PAHs and metals at concentrations slightly higher than those previously measured in urban run-off were asymptomatic Fig. 1.The presence or absence of the pre- spawn mortality syndrome in adult coho salmon exposed to unfiltered highway run- off (E) or clean well water (C). Paired exposures spanned three consecutive autumn spawning seasons, 2012–14. Shown in each panel are daily rainfall (shaded bars), cumulative rainfall (dotted lines), highway run-off collection intervals for each separate exposure event (black rectangles) and the presence or absence of symptomatic (or dead) fish in each individ- ual treatment (4–24 h duration; see Mate- rials and methods). Symptoms included lethargy, loss of orientation or loss of equilibrium. ©2015 The Authors. Journal of Applied Ecology ©2015 British Ecological Society,Journal of Applied Ecology,53, 398–407 Toxic urban run-off and salmon survival 401 North Ridgeview Estates Plat Hearing Examiner Packet Page 76 of 422 –that is behaviourally indistinguishable from controls exposed to clean well water (Table 1). Although there was some mortality across the four independent trials (n =4 of 30 fish total), this was not significantly different by treatment (Fisher exact tests, two-tailed,P ≥0 21) and was therefore apparently attributable to handling stress. Extending the exposures to 48 h did not increase the inci- dence of mortality or symptomology (n =4 of 22 fish total, two control and two exposed). Increasing the con- centrations of metals fivefold or 10-fold in metal-only mixtures was also insufficient to elicit the symptoms of the pre-spawn mortality syndrome (Table 2). As with the PAHs/metals mixture, there was a small but insignificant amount of mortality across treatments (n =2 of 38 fish; Fisher exact tests, two-tailed,P =1). Although the artificial storm water preparations were designed to have a similar composition to highway run- off for many PAHs and metals, the effects on coho spawners were very different. Whereas the artificial mix- tures did not elicit the distress characteristic of the mortal- ity syndrome, coho exposed to the unfiltered highway run-off rapidly became symptomatic. For every discrete rainfall collection interval (n =9; 2012–2014), all of the exposed fish were either symptomatic or dead within 4 h (Fig. 1, Table 3). Those that survived the initial 4-h expo- sure were dead by 24 h. All of the paired control coho in clean well water survived, showing no behavioural symp- toms at 4 or 24 h (Fig. 1, Table 3). Each exposure showed a statistically significant difference in mortality (Fisher exact tests, two-tailed,P =0 006). Examples of asymptomatic control fish and symptomatic, run-off- exposed spawners are shown in Video S3. For the purpose of comparing symptoms, digital movies of affected coho in Seattle-area urban watersheds are shown in Videos S1 and S2. Thus, despite the event-to-event variation in rain- fall duration and intensity, and a corresponding variation in water chemistry (conventionals, metals and PAHs, Tables S2, S3 and S5), urban run-off was 100% lethal to otherwise healthy adult coho salmon. The contribution of handling stress was evidently minimal, as the survival rate for controls across treatments in 2012–2014 was 100%. The constructed bioretention columns effectively treated the highway run-off in terms of both toxic chemical expo- sure and salmon spawner survival. Although the focal (measured) contaminants were not completely removed by infiltration, the overall improvement in water quality was sufficient to completely prevent the lethal effects and sub- lethal symptomology caused by untreated storm water. All of the adult coho exposed to filtered run-off survived and showed no behavioural symptoms at either 4 or 24 h (100% survival,n =20; Table 3; Video S3). Thus, urban storm water contains an as-yet unidentified chemical com- ponent(s) that, while lethal to salmon spawners, can be removed using inexpensive bioinfiltration. MEASURED LEVELS OF METALS, PAHS AND CONVENTIONAL WATER QUALITY PARAMETERS ACROSS TREATMENTS The chemical properties of highway run-off were evaluated for the six distinct collection events in the autumn of 2012 Table 1.Adult coho salmon spawner mortality following a 24-h exposure to either clean well water (unexposed) or a mixture of polycyclic aromatic hydrocarbons (PAHs) and metals. Shown in parentheses are the numbers of symptomatic or dead fish as a proportion of the total numbers of spawners in each exposure. The PAH/metal exposures were based on measured levels in urban creeks during storm events (see Materials and methods). Relative to environmental samples, the artificial mixture con- tained higher concentrations of both total PAHs and metals. Each exposure was conducted on a separate day Exposure (h) Mortality Unexposed PAHs/Metals mixture 24 25% (1/4) 0% (0/4) 24 33% (1/3) 0% (0/3) 24 0% (0/4) 50% (2/4) 24 0% (0/4) 0% (0/4) Table 2.Exposures to relatively high levels of metals in artificial mixtures are not sufficient to elicit the coho spawner mortality syndrome. Similar to unexposed controls, nearly all of the adults survived exposures to mixtures of metals (Cd, Cu, Pb, Ni, Zn) that were fivefold (Low) or 10-fold (High) higher than measured concentrations in urban creeks where coho mortality syndrome was observed. Shown in parentheses are the numbers of symp- tomatic or dead fish as a proportion of the total numbers of spawners in each exposure. Each exposure was conducted on a separate day Exposure (h) Mortality Unexposed Low metals High metals 24 0% (0/4) 0% (0/4) 24 0% (0/4) 0% (0/3) 24 0% (0/4) 0% (0/4) 24 25% (1/4) 25% (1/4) 24 0% (0/3) 0% (0/4) Table 3.Proportion of adult coho displaying the spawner mortal- ity syndrome after placement in clean well water (unexposed) or highway run-off that was either unfiltered or filtered through an experimental soil bioretention system (during 2013 and 2014). Shown in parentheses are the numbers of symptomatic or dead fish as a fraction of the total number of coho in each treatment. Each exposure was conducted on a separate day Exposure (h) Mortality Unexposed Unfiltered Filtered 4 0% (0/4) 100% (4/4) 0% (0/4) 24 0% (0/4) 100% (4/4) 0% (0/4) 24 0% (0/4) 100% (4/4) 0% (0/4) 24 0% (0/4) 100% (4/4) 0% (0/4) 24 0% (0/4) 100% (4/4) 0% (0/4) ©2015 The Authors. Journal of Applied Ecology ©2015 British Ecological Society,Journal of Applied Ecology,53, 398–407 402 J. A. Spromberg et al. North Ridgeview Estates Plat Hearing Examiner Packet Page 77 of 422 and 2013. As expected, conventional water quality parameters varied across storm water collections, as did concentrations of PAHs and metals. The analytical results are shown in Tables S2, S3 and S5. As expected, suspended solids (TSS: 23–220 mg L 1) and organic matter (DOC: 8–92 mg L 1) were elevated in urban run-off relative to control water (TSS <1 1mgL 1, DOC <1 8mgL 1). In contrast, run-off had lower Mg (t(8)=6 072,P <0 001), alkalinity (t(8)=6 201,P <0 001) and phosphate (t(8)=3 547,P =0 008). The pH values for run-off were circumneutral (6 12–7 47) and consistently lower than those for control water (t(8)=2 691,P =0 027). Other conven- tional chemistry parameters were not significantly different among treatments, including Ca (t(8)=0 121,P =0 907) and hardness (t(8)=1 159, P =0 280). At the outset of exposures, dissolved oxygen levels ranged from 8 1to107mgO2 L 1 and were main- tained above 6 5mgL 1 with additional aeration as needed. Collected highway run-off had a more pyrogenic (or combustion-driven) PAH profile relative to the artificial storm water mixtures, as evidenced by a relative enrich- ment of higher molecular weight (5- and 6-ring) com- pounds and fewer low molecular weight (2- and 3-ring) compounds (Fig. 2). Bile PAH metabolites were not sig- nificantly different between fish exposed to control well water or storm water run-off after a 4-h exposure (Fig. 3). Although the measured concentrations of PAH metabo- lites in the bile of fish exposed for 24 h to the PAHs/met- als mixture were elevated relative to paired controls, the difference was not significant (Student’s t-test;P =0 1, 0 14, 0 11 for phenanthrene, benzo-a-pyrene and naph- thalene metabolites, respectively). This indicates that low-level PAH exposures typical of urban run-off do not produce large increases in measurable bile metabolites, consistent with bile PAH metabolite measurements from symptomatic coho previously collected during field sur- veys of urban spawning habitats (Scholz et al.2011). Notably, in 2012, the levels of 2- and 3-ring PAHs in the control exposure water were unexpectedly elevated rel- ative to all other control treatments (Fig. 2, arrow). This was attributed to the recent drilling of a new well at the Suquamish hatchery facility. Measured PAH levels in the well water declined sharply over a time span of 2 weeks (Fig. 2), and adult coho controls that were exposed dur- ing the interval did not exhibit behavioural symptoms (Fig. 1). Whereas the levels of dissolved-phase Cd and Pb were generally lower in collected run-off relative to all of the artificial storm water mixtures (Fig. 2), Cu and Ni in run- off spanned the range of these two metals in the environ- mentally relevant mixture. Zinc levels in run-off were Fig. 2.Dissolved metal (left column) and dissolved polycyclic aromatic hydrocarbon (right column) concentrations summarized by ring number for adult exposures to well water controls, polycyclic aromatic hydro- carbons (PAHs)/metal mixtures, highway run-off and filtered run-off. Closed sym- bols indicate dead or symptomatic individ- uals were observed in the exposure. Lines connect paired highway run-off and fil- tered run-off from the same collection. Control points are the mean of samples collected each year. The number of mean values below the reporting limits (i.e. non- detects) is indicated by # ND. ©2015 The Authors. Journal of Applied Ecology ©2015 British Ecological Society,Journal of Applied Ecology,53, 398–407 Toxic urban run-off and salmon survival 403 North Ridgeview Estates Plat Hearing Examiner Packet Page 78 of 422 higher, and within the range of corresponding Zn levels in the high-metal mixture. The concentrations of metals in the gills of storm water-exposed and unexposed coho (4 h) were not significantly different (Student’s t-tests, P >0 05; Fig. 3) and, in both cases, were lower than gill metal levels measured from symptomatic spawners col- lected from the field (Scholz et al.2011). Similarly, expo- sures to the environmentally relevant artificial storm water mixture of PAHs/metals did not produce a signifi- cant accumulation of metals in the gills, with the excep- tion of Ni (Student’s t-test,P =0 017). For the high metals mixture, only gill Cd, Cu and Pb levels were signif- icantly elevated relative to controls (Student’s t-test; P =0 002, 0 018, 0 003 for Cd, Cu and Pb, respectively). Filtering collected highway run-off through the biore- tention columns reduced total PAHs by 94% and total metals by 58%. As expected, removal efficiency varied for different contaminants. For example, the soil columns removed lower molecular weight PAHs less efficiently than higher molecular weight PAHs (e.g. 81–89% for 2–3 ring PAHs vs. 93% removal of 4- to 5-ring PAHs; Table S5). Notably, the medium in the bioretention col- umns was a source (i.e. an exporter) of total Ni to the treated run-off, resulting in a 57% increase over the pre- filtration input (Table S3). All other total metals decreased by an average of 48–88% across the two events in the order of Cd <Pb <Cu <Zn. For each of the met- als, concentrations in the dissolved phase also declined after soil column infiltration (Table S3). In addition to exporting Ni, the bioretention columns were also a source of DOC (post-/pre-filtration increase of 164%), alkalinity (+29%), Ca (+60%), Mg (+372%), ortho-P (+4000%) and increasing hardness (+107%). By contrast, column infiltra- tion reduced the ammonia content of storm water by 92% (Table S2). Discussion We have confirmed that controlled exposures to untreated urban run-off are sufficient to reproduce the coho spaw- ner mortality syndrome. Adult coho became symptomatic and died within a few hours of immersion in collected storm water. Mortality rates were 100% for exposed fish vs. 0% in control fish held in clean well water, and these results were consistent across nine distinct rainfall inter- vals that spanned three consecutive autumn spawning runs. As evidence that one or more toxic chemical con- taminants are causal, pre-treating the highway run-off with soil bioinfiltration completely prevented the acutely lethal impacts on coho spawners. Surprisingly, coho did not develop symptoms in response to artificial mixtures of PAHs and metals, even at concentrations that were higher Fig. 3.Left column shows the relative measured concentrations of metals in adult coho salmon gill tissue for Cd, Cu, Pb, Ni and Zn (lgg 1). Control values are means of control tests run in 2011 and 2012. Closed symbols indicate dead or symp- tomatic individuals observed in the expo- sure. The right column shows bile fluorescent aromatic compounds (FACs) detected at naphthalene (NPH), phenan- threne (PHN), benzo-a-pyrene (BAP) wavelengths shown as protein corrected polycyclic aromatic hydrocarbons (PAH) equivalents (ng mg 1). ©2015 The Authors. Journal of Applied Ecology ©2015 British Ecological Society,Journal of Applied Ecology,53, 398–407 404 J. A. Spromberg et al. North Ridgeview Estates Plat Hearing Examiner Packet Page 79 of 422 than those typically measured in storm water, including the first flush. Urban run-off is chemically complex, with many chemical constituents that are very poorly charac- terized in terms of toxicity to fish. While it may take years of additional assessment to identify precisely which of these agents is killing coho, our initial results suggest that simple GSI technologies hold promise as a means to improve water quality and effectively prevent coho mor- tality in urban spawning habitats. Our finding that road run-off alone is sufficient to induce the spawner mortality syndrome aligns with previ- ous evidence for a positive association between the amount of impervious surface within an urban watershed and the year-to-year severity of coho die-offs (Feist et al. 2011). It appears that other forms of water quality degra- dation are not necessary to produce the phenomenon. Consistent with this, symptomatic spawners do not show evidence of neurotoxic pesticide exposure (Scholz et al. 2011), and adult coho are not unusually vulnerable to low-level mixtures of currently used pesticides (King et al. 2013). The link to impervious run-off also discounts a role for personal care products, pharmaceuticals, and other classes of compounds that are transported to some urban streams via combined sewer overflows in heavy rains. As noted above, urban road run-off contains a complex mixture of chemicals, many of which originate from motor vehicles in the form of exhaust, leaking crankcase oil and the wearing of friction materials (i.e. brake pads) and tyres. We assessed the toxicity of PAH and metal mixtures because these compounds are ubiquitous in storm water and are known to be disruptive to the fish cardiovascular system (PAHs: Brette et al.2014), as well as the respiratory and osmoregulatory functions of the gill (metals: Niyogi & Wood 2004). Although bile and gill tis- sue results suggest that PAHs and some metals are bioavailable to the coho spawners (this study; Scholz et al.2011), artificial mixtures of PAHs and metals did not produce the symptoms of the mortality syndrome. Our results appear to rule out many of the PAHs that are common to urban run-off and crude oil spills (e.g. phenanthrenes). However, there may be a role for the higher molecular weight pyrogenic PAHs found in partic- ulate vehicle exhaust (i.e. soot), other than pyrene or fluo- ranthene. The remaining list of potential causal chemicals is long and includes other organic hydrocarbons such as methylphenols, quinones, thiazoles, thiophenes, furans and quinolines. Given the logistical challenges associated with adult coho exposures –seasonal availability of ani- mals, large volume assays, limited number of fish, etc.–it may be years before the causal agent(s) is identified. Notably from a water resource management perspective, this will likely be a chemical or chemicals for which there are no existing water quality criteria. Biological indicators play an important role in field assessments to document the urban stream syndrome in affected watersheds world-wide. Common examples are benthic indices of biological integrity (B-IBIs), which are used to characterize the health of streams based on the diversity and abundance of macroinvertebrates (Karr 1999). Although poor B-IBI scores are diagnostic of aqua- tic habitat degradation, they do not necessarily differenti- ate between drivers that may be chemical (i.e. pollution) vs. physical or biological. Conversely, biological indica- tors that are specific to toxic run-off may not have directly meaningful implications for individual survival, as a basis for guiding species conservation at the population and community scales. This includes, for example, the upregulation of sensitive and responsive cytochrome p450 enzymes in the livers of fish exposed in situ to certain PAHs and other contaminants that act via the aryl hydro- carbon receptor (van der Oost, Beyer & Vermeulen 2003). Coho spawners, by contrast, appear to be very sensitive ecological indicators, with a response metric that is directly attributable to toxic storm water. Moreover, the implications of widespread and recurring mortality are relatively clear at higher scales (e.g. Spromberg & Scholz 2011). Although the highway run-off used in this study (at the point of discharge) presumably contained higher concentrations of chemical contaminants than surface water conditions in urban spawning habitats, it is evident that run-off in urban waterways is not sufficiently diluted to protect many or most coho from premature death (Scholz et al.2011). By establishing a direct link between non-point source pollution and the mortality syndrome, our findings set the stage for future indicator studies in western North America. This includes, for example, more refined predictive mapping of vulnerable habitats as a function of impervious land cover, at present and with future urban growth scenarios (Feist et al.2011). Coho survival in urban streams can also indicate the success of pollution control programmes, via GSI or other strategies. Intensive control measures will almost certainly be neces- sary, across large spatial scales, to: (i) recover viable coho populations in the built environment, and (ii) prevent the rapid future loss of coho as a consequence of expanding impervious cover in watersheds that are currently produc- tive but primarily non-urban. In the future, it may be possible to narrow the focal list of chemicals by determining more precisely why storm water-exposed coho are dying. The gaping, surface swim- ming and disequilibrium of affected spawners suggest adverse physiological impacts on the gill, the heart, the nervous system or some combination of these. An earlier forensic study found no evidence of physical injury to the gills or other tissues (Scholz et al.2011). An alternative approach would be to screen the target organs of symp- tomatic fish for changes in gene expression, and specifi- cally gene sets that are diagnostic for specific categories of physiological stress (e.g. respiratory uncoupling). If the cause of death is ultimately found to be heart failure, for example, the candidate chemicals could be screened for cardiotoxic potential. It may also be possible to develop alternative exposure methods that reflect different sources of contaminants on roadways. This includes, for example, ©2015 The Authors. Journal of Applied Ecology ©2015 British Ecological Society,Journal of Applied Ecology,53, 398–407 Toxic urban run-off and salmon survival 405 North Ridgeview Estates Plat Hearing Examiner Packet Page 80 of 422 large-volume suspensions of particulate soot from motor vehicle exhaust, dust from brake pad wear or fine parti- cles from tyre wear. Lastly, toxic run-off is likely to represent an increas- ingly important conservation challenge for west coast coho populations in the coming years. Extant population segments are generally at historically low abundances, as evidenced by current US Endangered Species Act threat- ened designations in central and northern California, as well as north-western Oregon and south-western Washing- ton. Land cover change has been extensive in some low- land watersheds where coho spawn, as a consequence of sprawl in recent decades (e.g. Robinson, Newell & Mar- zluff 2005). Over a similar period of time, coho habitat use in areas affected by urbanization has declined sharply (Bilby & Mollot 2008). Resource managers have been aware of the urban pre-spawn mortality syndrome among adult coho since at least the 1980s (Kendra & Willms 1990). However, the extent to which recurring adult die- offs have driven down wild coho numbers in urbanizing watersheds is not presently known. Initial modelling has shown that local populations in urbanizing watersheds cannot withstand the rates of mortality observed in Puget Sound urban stream surveys since 2000 (Spromberg & Scholz 2011). However, in terms of recovery planning, this storm water-related threat has yet to be mapped out for actual coho conservation units at the sub-basin scale. In conclusion, a core objective of GSI is to slow, spread and infiltrate storm water. As anticipated from recent studies (e.g. McIntyre et al.2015), the experimental soil columns used here effectively prevented the acutely lethal toxicity of run-off from a dense urban arterial road. This extends the range of aquatic species and life stages that demonstrably benefit from storm water bioinfiltration. These include the early life stages of zebrafish (McIntyre et al.2014), juvenile coho salmon and their macroinverte- brate prey (McIntyre et al.2015), and adult coho spawn- ers (this study). Bioretention is therefore a promising clean water technology from the standpoint of installation cost, reliability, reproducibility and scalability. However, the science of GSI effectiveness is still relatively young (Ahiablame, Engel & Chaubey 2012), and fundamental questions remain as-yet unanswered, for example how much treatment will be needed, over what spatial scales, to ensure coho salmon survival? Whereas bioretention may work well for small-footprint sites that receive mod- est inputs of storm water, they are but one of many evolv- ing non-point source pollution control and prevention methods that are currently under development (Hughes et al.2014). For the urban watersheds of the future, the coexistence of humans and wild coho will likely hinge on the success of these innovations. Acknowledgements We appreciate the technical assistance of Allisan Beck, Richard Edmunds, Tony Gill, Emma Mudrock, Tiffany Linbo, Kate Macneale, Jana Labenia, Mark Tagal, Frank Sommers, Gina Ylitalo, Daryle Boyd, Barb French, Ann England, Karen Peck, MaryJean Willis, Cathy Laetz, Sylvia Charles, William Alexander, Ben Purser, Corey Oster, Luke Williams and the Kit- sap Poggie Club. This study received agency funding from the NOAA Coastal Storms Program (National Ocean Service, Coastal Services Cen- ter), the U.S. Fish & Wildlife Service, the Puget Sound’s Regional Stormwater Monitoring Programme (RSMP as administered by the WA State Dept. of Ecology), and the U.S. Environmental Protection Agency, Region 10. Lastly, we appreciate the helpful suggestions of two anony- mous reviewers. Findings and conclusions herein are those of the authors and do not necessarily represent the views of the sponsoring organizations. Data accessibility Data generated from this study are included in the text, tables, figures and uploaded online supporting information. References Ahiablame, L.M., Engel, B.A. & Chaubey, I. (2012) Effectiveness of low impact development practices: literature review and suggestions for future research.Water Air and Soil Pollution,223, 4253–4273. Bilby, R.E. & Mollot, L.A. 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(2011) Estimating the future decline of wild coho salmon populations due to early spawner die-offs in urbaniz- ing watersheds of the Pacific Northwest.Integrated Environmental Assessment and Management,7, 648–656. Stein, E.D., Tiefenthaler, L.L. & Schiff, K. (2006) Watershed-based sources of polycyclic aromatic hydrocarbons in urban storm water.En- vironmental Toxicology and Chemistry,25, 373–385. Tiefenthaler, L.L., Stein, E.D. & Schiff, K.C. (2008) Watershed and land use-based sources of trace metals in urban storm water.Environmental Toxicology and Chemistry,27, 277–287. Walsh, C.J., Roy, A.H., Feminella, J.W., Cottingham, P.D., Groffman, P.M. & Morgan, R.P. II (2005) The urban stream syndrome: current knowledge and the search for a cure.Journal of the North American Benthological Society,24, 706–723. Waples, R.S. (1991) Pacific salmon,Oncorhynchus spp., and the definition of “species” under the Endangered Species Act.Marine Fisheries Review,53,11–22. Washington Department of Ecology (2012) Stormwater Management Manual for Western Washington Volume V: Runoff Treatment BMPs. Publication No. 12-10-030, 301 pp. Washington Department of Ecol- ogy, Olympia, Washington, USA. Washington State Department of Transportation (WA DOT) (2013a)2012 Annual Traffic Report, 231 pp. WA DOT, Olympia, Washington, USA. Washington State Department of Transportation (WA DOT) (2013b) State Highway Log Planning Report 2012: SR2 to SR 971, 1781 pp. WA DOT, Olympia, Washington, USA. Received 2 April 2015; accepted 2 September 2015 Handling Editor: Julia Blanchard Supporting Information Additional Supporting Information may be found in the online version of this article. Table S1. Nominal concentrations (lgL 1) for metals and selected polycyclic aromatic hydrocarbons (PAHs) in the PAHs/ metals mixture and the metals-only mixture exposures. Table S2. Measured conventional water chemistry parameters in treatments used in adult coho experiments during 2012–2013. Table S3. Measured metal concentrations in treatments used in adult coho experiments during 2012–2013. Table S4. Abbreviations and polycyclic aromatic hydrocarbon (PAH) analytes, including sums of alkyl PAH isomers measured in water samples. Table S5. Measured parent and alkylated homologue polycyclic aromatic hydrocarbons (PAHs) (lgL 1) in treatments used in adult coho experiments during 2012–2013. Video S1. Video 1 of a symptomatic adult coho spawner in a Seattle-area urban stream. Video S2.Video 2 of a field observation of a symptomatic adult coho in a Seattle-area urban stream. Video S3. Adult coho spawners exposed under controlled experi- mental conditions to either clean well water, unfiltered urban run- off, or run-off treated using bioinfiltration. ©2015 The Authors. Journal of Applied Ecology ©2015 British Ecological Society,Journal of Applied Ecology,53, 398–407 Toxic urban run-off and salmon survival 407 North Ridgeview Estates Plat Hearing Examiner Packet Page 82 of 422 Landscape Ecotoxicology of Coho Salmon Spawner Mortality in Urban Streams Blake E. Feist 1*, Eric R. Buhle 1, Paul Arnold 2, Jay W. Davis 2, Nathaniel L. Scholz 1 1 Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Seattle, Washington, United States of America, 2 Washington Fish and Wildlife Office, United States Fish and Wildlife Service, Lacey, Washington, United States of America Abstract In the Pacific Northwest of the United States, adult coho salmon (Oncorhynchus kisutch) returning from the ocean to spawn in urban basins of the Puget Sound region have been prematurely dying at high rates (up to 90% of the total runs) for more than a decade. The current weight of evidence indicates that coho deaths are caused by toxic chemical contaminants in land-based runoff to urban streams during the fall spawning season. Non-point source pollution in urban landscapes typically originates from discrete urban and residential land use activities. In the present study we conducted a series of spatial analyses to identify correlations between land use and land cover (roadways, impervious surfaces, forests, etc.) and the magnitude of coho mortality in six streams with different drainage basin characteristics. We found that spawner mortality was most closely and positively correlated with the relative proportion of local roads, impervious surfaces, and commercial property within a basin. These and other correlated variables were used to identify unmonitored basins in the greater Seattle metropolitan area where recurrent coho spawner die-offs may be likely. This predictive map indicates a substantial geographic area of vulnerability for the Puget Sound coho population segment, a species of concern under the U.S. Endangered Species Act. Our spatial risk representation has numerous applications for urban growth management, coho conservation, and basin restoration (e.g., avoiding the unintentional creation of ecological traps). Moreover, the approach and tools are transferable to areas supporting coho throughout western North America. Citation:Feist BE, Buhle ER, Arnold P, Davis JW, Scholz NL (2011) Landscape Ecotoxicology of Coho Salmon Spawner Mortality in Urban Streams. PLoS ONE 6(8): e23424. doi:10.1371/journal.pone.0023424 Editor:Howard Browman, Institute of Marine Research, Norway Received January 31, 2011;Accepted July 17, 2011;Published August 17, 2011 This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication. Funding:This work was supported by the National Oceanic and Atmospheric Administration - Coastal Storms Program; U.S. Fish and Wildlife Service - National Contaminants Program; City of Seattle (Seattle Public Utilities); and the U.S. Environmental Protection Agency - Region 10. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests:The authors have declared that no competing interests exist. * E-mail: blake.feist@noaa.gov Introduction In recent decades, human population growth and development have continued to increase along the coastal margins of North America [1]. The associated changes in land cover and human land use have elevated land-based sources of pollution, and toxic stormwater runoff in particular, to become one of the most important threats to the biological integrity of basins, lakes, estuaries, and nearshore marine environments [2]. In the United States, concerns related to non-point source pollution have gained momentum over the past decade (e.g., [3,4]). This has culminated most recently in the designation of ‘‘water quality and sustainable practices on land’’ as one of nine National Priority Objectives for the newly established National Ocean Council, together with ecosystem-based management, marine spatial planning, climate change and ocean acidification, and changing conditions in the Arctic [2]. For toxic runoff, however, the connections between unsustainable practices on land and the decline of ecological resilience in aquatic habits remain poorly understood. In western North America, semelparous anadromous salmonids (Oncorhynchus spp.) typically migrate thousands of kilometers in their lifetimes. They hatch and rear in freshwater, migrate seaward to capitalize on the productivity of the oceans to grow rapidly and reach sexual maturity, and then return to their natal streams to spawn and die. Certain salmonids, including pink (O. gorbuscha) and chum (O. keta) migrate to the ocean relatively soon after hatching. Others, however, such as Chinook (O. tshawytscha), steelhead, (O. mykiss), sockeye (O. nerka), and coho (O. kisutch) may spend one or more years in freshwater lakes, rivers and streams. Because of this extended freshwater residency, juveniles of these species are potentially more vulnerable to anthropogenic modifications of freshwater habitat quality [5]. In contrast to the high mortality experienced by juvenile salmonids, mortality at the adult spawner life stage is relatively low. Familiar natural causes of mortality include predation, disease [6,7,8,9], stranding (following high flows), elevated stream temperatures, and competition – e.g., in habitats with abundant salmon returns and limited spawning substrate. Various human activities such as recreational and commercial fishing, stream dewatering, and the placement of migration barriers can also increase salmon spawner mortality. In general, however, salmon spawner mortality has not been attributed to toxic chemical contaminants in stormwater runoff – a data gap that may be due, in part, to 1) the relative rarity of salmon spawners in urban basins with poor water quality, and 2) the logistical difficulty of implementing toxicity studies on migratory, seawater-to-freshwa- ter transitional adults. The exception is a recently documented phenomenon of returning adult coho salmon dying at high rates in urban and urbanizing streams in lowland Puget Sound region, which includes PLoS ONE | www.plosone.org 1 August 2011 | Volume 6 | Issue 8 | e23424 North Ridgeview Estates Plat Hearing Examiner Packet Page 83 of 422 the greater Seattle metropolitan area [10]. Coho return to small coastal stream networks to spawn each fall. Entry into freshwater is triggered by early autumn rainfall and rising stream flows. Since there had been extensive habitat degradation and loss in these lowlands, many basins were targeted for stream restoration projects in the 1990s. Subsequent surveys to evaluate project effectiveness discovered that many coho salmon were dying in newly-accessible stream reaches before they were able to spawn – i.e., female carcasses were found in good condition (ocean bright colors) with skeins (membrane or sac that contains the eggs within the fish) filled with unspawned eggs [10]. In addition, affected coho from several different urban basins showed a similar progression of symptoms leading up to death, including disorientation, lethargy, loss of equilibrium, mouth gaping, and fin splaying. Systematic daily spawner surveys in recent years (2002–2009) have shown that adult mortality rates in urban streams are consistently high (relative to spawning coho salmon in more pristine areas), ranging from ,25–90% of the total fall runs [10]. Mortality rates of this magnitude likely have important negative consequences for maintaining viable coho populations [11]. Consistent with this, most coho mortalities observed over the past decade were spawners that strayed (did not home to their natal stream reaches) into these restored urban freshwater habitats. The precise underlying cause of recurrent coho die-offs remains under investigation. An initial weight-of-evidence forensic study has systematically ruled out stream temperature, dissolved oxygen, poor overall spawner condition, tissue pathology (e.g., gill), pathogen prevalence or disease, and other factors commonly associated with fish kills in freshwater habitats (Scholz et al., unpublished data). These findings, together with the rapid onset of the syndrome, the nature of the symptoms (e.g., gaping and disequilibrium), and the consistent re-occurrence within and between urban basins over many years together point to toxic stormwater runoff from urban landscapes as the likely cause of coho spawner mortality. Urban runoff and stormwater-influenced combined sewer overflows (CSOs) contain an exceptionally complex mixture of chemical contaminants. Specifically, urban streams are receiving waters for runoff and discharges containing pesticides [12], metals [13], petroleum hydrocarbons [14], plasticizers, flame-retardants, pharmaceuticals, and many other potentially toxic chemicals. The list of possible causal agents is therefore long. The above chemical complexity notwithstanding, there are several reasons to suspect motor vehicles as sources of toxics that are killing returning coho. Vehicles deposit many compounds on road surfaces via exhaust emissions, leaking fluids, and the wearing of tires, brake pads and other friction materials [15]. Emissions contain nitrogen and sulfur dioxide, benzene, formaldehyde, and a large number of polycyclic aromatic hydrocarbons (PAHs). Fluids, including antifreeze and motor oil, contain ethylene and propylene glycol and PAHs. Tire wear releases zinc, lead, and PAHs onto road surfaces [16], and brake pad wear is a major source of copper, zinc, nickel, and chromium [16,17]. Collectively, these contaminants accumulate on streets and other impervious surfaces until they are mobilized by rainfall and transported to aquatic habitats via runoff. Polycyclic aromatic hydrocarbons and metals such as copper are known to be toxic to fish, although acute lethality usually occurs at exposure concentrations that are higher (by orders of magnitude) than those typically detected in urban streams. It is likely that fall stormwater pulses contain higher concentrations than winter and spring due to the potential buildup of contaminants during the relatively dry summer months. Although the adult die-off phenomenon has been observed in all Seattle-area urban streams where coho salmon occur, the overall rate of mortality has varied among basins. In qualitative terms, a higher proportion of returning animals have survived to spawn in basins that have more open space (e.g., parks and woodlands). Conversely, mortality rates have been consistently higher in basins with proportionately greater ‘‘urban’’ land cover and land uses. This raises the possibility of a quantitative relationship between discrete basin characteristics and coho survival and spawning success. Such a relationship would be important for several reasons. First, if coho mortality is significantly correlated with one or more land cover or land use variables, the latter could be used to identify unmonitored lowland basins where coho populations are at greatest risk. Second, it could provide a means to evaluate how future human population growth and development might impact wild coho populations in Puget Sound (and elsewhere) that are currently healthy. Finally, it could narrow the list of potentially causative pollution sources in urban basins, thereby focusing future toxicological studies to identify the specific contaminants involved. In this study we performed a spatial analysis to identify landscape variables that correlate most closely with surveyed rates of coho spawner mortality across six different basins in Puget Sound. The variables included land use and land cover, tax parcel types, roadways, and impervious surfaces. We then used the information from these correlations to generate spatially explicit predictions of recurrent spawner losses in unmonitored basins throughout the four most densely populated counties in the greater Seattle metropolitan area. Materials and Methods Study Sites We characterized habitat conditions within the drainage basins from streams at six sites in the Puget Sound lowlands (Figure 1). We chose these sites because coho spawner mortality has been monitored at these locations for several years (2000–2009; [10]). The sites represent a wide range of anthropogenic alteration, from highly urbanized (e.g., Longfellow Creek) to relatively undisturbed (e.g., Fortson Creek). Fortson Creek is considered a non-urban site, whereas the other five sites are urban streams and have varying degrees of development. The urban streams have all been a focus of varying restoration project efforts aimed at enhancing habitat quality for anadromous Pacific salmon. With the exception of the relatively unaltered Fortson Creek site, all site basins had impervious surface proportions well above the levels (5–10%) commonly associated with the decline of biological integrity in streams [18,19]. Confirmed observation of the coho spawner mortality syndrome (see below) within a stream system was a key factor in study site selection. Importantly, natural production of coho in Seattle-area urban streams is very low. Not unexpectedly, recent modeling has shown that local coho population abundance declines precipitous- ly at rates of spawner mortality documented for these drainages [11]. The adult returns to these streams are thus likely to be animals straying into sink or attractive nuisance habitats. Conversely, the syndrome has not been documented in streams where coho are relatively abundant – i.e., non-urban basins, as confirmed by a full season of daily stream surveys on Fortson Creek. Therefore, to evaluate the phenomenon in relation to land cover, we were constrained to streams where coho are affected, even if adult returns to these basins were low in certain years. Lastly, there is no evidence that the mortality syndrome is related to the origin of the spawners (i.e., hatchery vs. wild fish). For example, artificially propagated coho that return as adults to regional hatchery facilities in non-urban basins are unaffected. Ecotoxicology of Salmon Mortality in Urban Streams PLoS ONE | www.plosone.org 2 August 2011 | Volume 6 | Issue 8 | e23424 North Ridgeview Estates Plat Hearing Examiner Packet Page 84 of 422 Study Subjects Coho salmon in this study were all within the Puget Sound/ Strait of Georgia Evolutionarily Significant Unit (ESU). An ESU is defined as a group of populations that 1) are substantially reproductively isolated from conspecific populations and 2) collectively represent an important component in the evolutionary Figure 1. Six study sites where coho spawner mortality was monitored and landscape conditions were quantified.Main map depicts the Greater Seattle Metropolitan Area in Washington State, which is within the Puget Sound/Georgia Basin of the Pacific Northwest, United States of America (USA). Inset map illustrates location of the study sites within Washington State and the location of Washington State within the USA. For reference, red shading on main map represents the relative intensity of urbanization (light-medium and dense urban [23,24]). Drainage basins depicted in yellow shaded polygons represent the total basin flowing into a given stream reach site. Key for site numbers: 1=Des Moines; 2=Fauntleroy; 3=Fortson; 4=Longfellow; 5=Piper’s; and, 6=Thornton Creek. doi:10.1371/journal.pone.0023424.g001 Ecotoxicology of Salmon Mortality in Urban Streams PLoS ONE | www.plosone.org 3 August 2011 | Volume 6 | Issue 8 | e23424 North Ridgeview Estates Plat Hearing Examiner Packet Page 85 of 422 legacy of the species [20]. Currently, Puget Sound/Strait of Georgia coho are designated a ‘‘species of concern’’ under the U.S. Endangered Species Act [21]. Coho typically spawn in small (lower order) streams in the Puget Sound lowlands in late fall and early winter and their fry emerge from stream substrates from March to May. Fry reside in riverine habitats for 14–18 months, smolt, migrate to marine environments where they grow rapidly and mature (16–20 months), and finally migrate to their natal basins where they spawn and die [22]. The adult spawners from the six study basins were both marked (adipose fin clipped) and unmarked, suggesting a mix of hatchery and wild origins. Coho Spawner Mortality We used existing monitoring data collected as part of daily and weekly spawner surveys in each of the six study locations (Table 1). Data were collected during the fall spawning season from 2000– 2009 by Seattle Public Utilities (SPU), the Wild Fish Conservancy, and the Northwest Fisheries Science Center (NWFSC). Streams were checked every few days in the early fall (usually the first or second week in October, depending on rainfall) until the first adult coho was observed. The streams were then surveyed daily for the duration of the fall run, until the last carcass was documented, typically in the first or second week of December. For several years, biologists working for the City of Seattle (Wild Fish Conservancy) also surveyed many of the same urban streams for coho spawner mortality on a weekly basis. Side-by-side compar- isons of daily and weekly survey data (e.g., for Longfellow Creek in 2005 and 2007) revealed practically no loss of carcasses to scavengers. Accordingly, we included the weekly survey data in our analyses. The entirety of the available spawning habitat within a given urban drainage was surveyed for premature adult coho mortality. For some streams, including Longfellow Creek, mid-stream barriers to upstream migration confined adults to the lower portions of the drainage. This made it possible, in the course of a few hours as part of a daily survey, to inspect all sections of the stream that 1) had a gravel substrate suitable for redds (spawning ‘‘nests’’ built by females), and 2) were focal areas for repeated (year-to-year) redd building during successive spawner runs. Monitoring data were not collected at all sites for all years (Table 1). Mortality among returning coho was quantified only for females on the basis of egg retention – i.e., the number of partially spawned or unspawned female carcasses observed in streams over an entire spawning season. Notably, the total number of returning adults was low for some years and some basins (Table 1). Nevertheless, the aggregate spawner survey data used in this analysis are the most comprehensive currently available. Geospatial Datalayers We used existing geospatial datalayers as our source of potential predictor variables and as a proxy for habitat type and condition. The datalayers were generated by a variety of organizations for planning and analytical purposes, making them suitable for running spatial analyses on habitat. They were also available over the entire spatial domain of our predictive model. We used four geospatial datalayers: Land-cover of the Greater Puget Sound Region [23,24]; impervious and impacted surfaces [25]; property type (compiled from King [26], Kitsap [27], Pierce [28] and Snohomish county [29] tax parcel databases), and roadways (Puget Sound Regional Council; PSRC [30]). The Land-cover of Puget Sound datalayer is the highest quality and most accurate depiction of land use and land cover in the Puget Sound lowlands. The datalayer used 30 m gridded LAND- SAT TM imagery from 2002, which was extensively analyzed and corrected to produce an accurate (83% overall accuracy, [24]) depiction of land use and land cover conditions. To reduce the total number of potential predictor variables, we only used the dense urban (.75%); light to medium urban (,75%); and grass, crops and/or shrubs categories. We also combined the mixed and deciduous forest with the coniferous forest category and named it forests. The impervious and impacted surfaces datalayer was derived from a 2001 LANDSAT TM image with 30 m pixels and an accuracy of 83–91% [25]. This datalayer depicts high to completely impermeable surfaces such as building roofs; concrete or asphalt roads and parking lots; concrete, asphalt or brick sidewalks, pedestrian walkways, and malls; etc. One of the limitations of these two datalayers was that the pixel size of the source LANDSAT TM imagery is 30 m, so smaller Table 1.Coho spawner mortality proportion and cumulative number of female carcasses enumerated (in parentheses) by site (columns) and year (rows). Des Moines Fauntleroy Fortson 1 Longfellow Piper’s Thornton 2000 - 0.25 (12) - 0.74 (135) 0.18 (17) 0.88 (33) 2001 - 0.22 (9) - 0.61 (111) 0.70 (37) 0.82 (11) 2002 - 0.00 (1) 0.01 (114) a 0.86 (57) a 0.60 (10) 080 (5) 2003 - (0) - 0.67 (18) a 0.00 (1) 1.00 (2) 2004 0.63 (30) a (0) - 0.89 (9) a 0.33 (3) 1.00 (1) 2005 - 0.75 (4) - 0.72 (75) a 0.75 (4) 0.50 (8) 2006 - (0) - 1.00 (4) a 1.00 (9) a 1.00 (4) 2007 - 0.75 (4) - 0.73 (41) a 0.20 (5) 0.80 (5) 2008 - - - 0.67 (12) a - 1.00 (2) 2009 - - - 0.78 (36) a -- Overall 0.63 (30) 0.37 (30) 0.01 (114) 0.72 (498) 0.57 (86) 0.83 (71) A dash (-) indicates survey was not conducted for that year/site. aNorthwest Fisheries Science Center (NWFSC) daily surveys, all others were weekly and collected by Seattle Public Utilities (SPU) or the Wild Fish Conservancy [51,52]. 1Non-urban site. doi:10.1371/journal.pone.0023424.t001 Ecotoxicology of Salmon Mortality in Urban Streams PLoS ONE | www.plosone.org 4 August 2011 | Volume 6 | Issue 8 | e23424 North Ridgeview Estates Plat Hearing Examiner Packet Page 86 of 422 features, such as roads and precise land cover boundaries, were not adequately captured. In order to address this deficiency, we analyzed property types and roadways, as they are represented as precise polyline and polygon delineations of the corresponding land cover variables. The boundaries in these geospatial datalayers were derived from precise survey data from major metropolitan areas, collected over many years by King, Kitsap, Pierce and Snohomish Counties. The property types (parcels) datalayer was based on ground surveyed delineations of property, which are used for taxation purposes, with positional accuracy of +/212 m or less [26,27,28,29]. The original number of parcel types described by each county was between 103 and 292. Using the descriptions in the documentation that accompanied the datalayers, we were able to place each of the original parcel types into one of the five following categories: apartments and condominiums; commercial; industrial; parks and open space; and, residential. The roadways datalayer was based on ground surveyed road and street centerlines. Each segment had a corresponding functional classification (FC##) code and width, as defined by the Federal Highway Administration [31] Highway Performance Monitoring System, and the Puget Sound Regional Council [30], respectively. We reduced the original nine functional classification types down to two categories: 1) heavily used roads (rural minor collector [FC08]; urban principal arterial - interstate [FC11]; urban principal arterial - other freeways and expressways [FC12]; urban principal arterial - other [FC14]; urban or rural minor arterial [FC16 or FC06]; urban collector [FC17]); and, 2) urban or rural local access roads (FC09 or FC19). We then calculated the total area (total length of given street centerline segment multiplied by its width) of each street functional classification for each corresponding site basin. Spatial Analyses We defined the area of influence of the surrounding landscape for each site as the total area draining into that site (basin). Drainage basins for each site were generated using the ‘flowaccumulation’ command in Environmental Systems Research Institute (ESRI) ArcGIS (v. 9.3). We used a United States Geological Survey (USGS) 10 m digital elevation model (DEM) as the underlying terrain for generating basins. We then intersected the corresponding basin boundary for each of the six sites with each of the geospatial datalayers and their associated categories using ArcGIS. We quantified each geospatial datalayer and its associated category in a given basin as the fraction or proportion of the total area of the basin occupied by that geospatial datalayer or category. Longfellow Creek stood apart from the other sites in terms of the accuracy of the flow accumulation model because an unknown fraction of stormwater runoff in this drainage is diverted into the municipal sewer system. Therefore, the theoretical basin area, based on the terrain represented in the DEM, was not as representative of the true basin area compared with the other five sites. Statistical Analyses We used generalized linear mixed-effects models (GLMMs; [32,33]) to test the relationships between geospatial variables and coho spawner mortality. The response was binomial (observed number of female spawner mortalities each year, given the total number of female coho that returned to each site) and the models used a logit link function. All models included a random effect of site on the intercept, which accounts for nonindependence of the repeated samples taken at each site. We constructed a set of 139 candidate models by considering all combinations of the 12 predictors taken one, two, three or four at a time, with the restriction that a model could include at most one predictor from each of the four geospatial datalayers (land cover, impervious surfaces, property types, and roadways). We also excluded combinations of predictors that had a pairwise Spearman rank correlation exceeding 0.9 in absolute value. The candidate set included an intercept-only model as a no-effect baseline against which we could assess the predictive power of the geospatial variables. We fitted the models using the Laplace approximation to the marginal likelihood [32] in the lme4 package in R [34,35]. We then used Akaike’s information criterion, corrected for sample size (AICc) to rank the strength of evidence for each candidate model based on the data. Akaike’s information criterion is a weight-of- evidence measure that reflects the balance between a model’s goodness-of-fit to the data and its parsimony (i.e., number of parameters). Lower AICc values indicate greater support, and are reported as differences (DAICc) relative to the best (smallest) value in the candidate set. We computed Akaike weights [36], which represent the relative support for each model, normalized so the weights sum to unity across the candidate set. We used these weights to compute model-averaged estimates and unconditional standard errors (SEs) for the fixed regression coefficients, and we quantified the relative importance of each predictor using variable weights (i.e., the summed Akaike weights of all models that included that predictor; [36]). These model averaging calculations were based on the 95% confidence set of models (i.e., the top- ranked models whose cumulative Akaike weight is 0.95), after re- normalizing the weights. Mapping coho spawner mortality Using the fitted models, we built a map of predicted coho spawner mortality throughout the four counties (King, Kitsap, Pierce and Snohomish) representing much of the Puget Sound lowlands, by applying the GLMM equations to geospatial data from unmonitored basins. We used basins delineated in the National Hydrography Dataset Plus [37] as the underlying mapping unit (300 ha mean, 466 ha SD) and intersected the NHDPlus datalayer with each of the geospatial datalayers used in the statistical analyses. Within the four-county region, we only made spawner mortality predictions in basins where coho salmon presence has been documented, based on current geospatial datalayers generated by the Washington Department of Fish and Wildlife [38]. We then calculated the proportion of each basin that was covered by the selected landscape feature. We generated predicted values of the proportion of mortalities from each model in the 95% confidence set and then model-averaged these values using the normalized Akaike weights [36]. These predictions apply to the average basin in the Puget Sound coho ESU with some given set of habitat conditions, in the sense that the random effect of site was set to zero. To be conservative in representing the precision of the predicted values, we divided the calculated rates of likely coho spawner mortality into three bins:,10%, 10–50%, and .50%. These break points were chosen somewhat arbitrarily to represent low, medium and high spawner mortality rates. Results We found strong associations between land use and land cover attributes and rates of coho spawner mortality. Across the 95% confidence set of fitted models, three variables were particularly important for predicting mortality based on high variable weights: impervious surfaces, local roads, and commercial property type (Table 2 and Figure 2). There was substantial model selection Ecotoxicology of Salmon Mortality in Urban Streams PLoS ONE | www.plosone.org 5 August 2011 | Volume 6 | Issue 8 | e23424 North Ridgeview Estates Plat Hearing Examiner Packet Page 87 of 422 uncertainty, reflected in a large 95% confidence set and large number of models with DAICc,2.0 (37 and 8 of 139 candidate models, respectively; Table 3). In addition, although we excluded highly multicollinear combinations of variables (|r|.0.9), many variables were still strongly correlated, resulting in unstable parameter estimates and large unconditional SE estimates (Table 2). Nonetheless, predictive models that included land use and land cover attributes as predictors were clearly superior to the intercept-only model (DAICc =20.4; Table 3), supporting the association of these variables with coho mortality. While the multicollinearity among potential predictors made causal interpretation of the models difficult, it did not preclude predictions of where coho salmon are likely to be affected along an urbanization gradient. Not surprisingly, the highest predicted mortality rates were clustered around the major metropolitan areas of eastern Puget Sound, contained within Snohomish, King, Kitsap, and Pierce counties (Figure 3). In addition, there is a significantly sized area in Eastern Puget Sound that has considerable proportions of the variables (local roads, impervious surface and commercial parcels) most correlated with substantial mortality rates. It is important to note that these predicted values have substantial associated uncertainty and should therefore be interpreted cautiously; however, it is reasonable to use them for assigning the break points for the low, medium, and high mortality rate categories represented on the map. Discussion Overall, we have used conventional tools in landscape ecology to shed light on an unusually complex ecotoxicological challenge. Our analyses strongly suggest that specific characteristics of basins in the Puget Sound lowlands are linked to the die-offs of coho spawners that have been widely observed in recent years. Across basins, the strength of the association is greatest for impervious surfaces, local roads, and commercial property. We did not evaluate hydrologic or geomorphic basin characteristics as part of our analysis. Nevertheless, our findings support the hypothesis that coho are being killed by as-yet unidentified toxic chemical contaminants that originate from these types of surfaces and are transported to salmon spawning habitats via stormwater runoff. Our results extend a large body of scientific information linking urbanization (broadly defined) and degraded water quality to a loss of biological integrity (sensu Karr [39]) and productivity in freshwater stream networks [18,40,41]. Previous studies have generally related land use and land cover variables to macroin- vertebrate assemblages in streams [42], or to the relative abundance of salmon and other fish (e.g., [22,43,44]). The present analysis is novel because it relates basin characteristics directly to salmon health and survival, versus species presence or absence. Moreover, it offers new insights on the water quality aspects of urban runoff. The focus of most salmon restoration projects is physical characteristics of spawning and rearing habitat [45]. Most salmon specific restoration projects are deemed successful if they simply restore the physical habitat to a suitable state for a given species [46]. Our study suggests that suitable spawning and rearing habitat may not be supportive of coho salmon persistence when the surrounding landscape is urbanized. The linkages between increased impervious coverage within a basin, increased storm- water runoff, altered hydrologic processes, and ecological decline are well established (e.g., [18]). However, stormwater impacts encompass both physical and chemical drivers of decline, and it can be difficult to distinguish between these via in situ assessments because stream invertebrate communities integrate both stressor categories. Coho salmon spawners, by contrast, appear to be promising and specific sentinels for the degraded water quality aspect of urban runoff. Compared to macroinvertebrate sampling and taxa identification, the coho mortality syndrome is relatively easy and inexpensive for non-specialists to monitor in the form of digital video recordings of symptomatic fish, or the presence of unspawned female carcasses in streams. Interestingly, the mortality syndrome appears to be specific to coho salmon. For example, there were temporally overlapping runs of coho and chum salmon (O. keta) in Piper’s Creek in the fall of 2006. Whereas all of the adult coho succumbed to the mortality syndrome, the chum were unaffected, with nearly all surviving to spawn (130 of 135 spawned out female carcasses; Scholz et al., unpublished data). Consistent with this, the survey Table 2.AIC weights, model averaged parameter estimates and unconditional confidence intervals for each variable, ranked by AICc weight. Model AICc Averaged Unconditional Datalayer Variable weight coefficient SE Impervious Impervious surfaces 0.7158 16.8425 14.5376 Roadways Local roads 0.5647 215.6199 68.3331 Property type Commercial 0.5107 7.9375 8.2616 Land cover Dense urban 0.3865 27.7776 16.1614 Property type Apartments & condominiums 0.2409 29.5330 31.1917 Roadways Heavily used roads 0.2019 5.3445 31.5073 Land cover Forest 0.1163 20.7793 6.2249 Land cover Light to medium urban 0.1149 0.3250 2.9751 Land cover Grass, shrubs & crops 0.0993 0.1664 5.4517 Property type Residential 0.0975 0.0738 16.8920 Property type Industrial 0.0547 20.2475 4.7008 Property type Parks & open space 0.0000 0.0000 0.0000 doi:10.1371/journal.pone.0023424.t002 Ecotoxicology of Salmon Mortality in Urban Streams PLoS ONE | www.plosone.org 6 August 2011 | Volume 6 | Issue 8 | e23424 North Ridgeview Estates Plat Hearing Examiner Packet Page 88 of 422 teams have not observed the characteristic symptoms (e.g., surface swimming, gaping) among other fish species that inhabit urban streams such as sticklebacks and cutthroat trout. Not only are coho unusual in this respect, the phenomenon appears to be restricted to the adult life stage. In the fall of 2003, surface flows from Longfellow Creek were diverted through streamside sheds housing aquaria that contained individual juvenile coho from the NWFSC hatchery. The juveniles (n=20) were maintained and observed daily throughout the fall spawner run. Overall juvenile survival was 100%, and the juveniles behaved normally, even on days when symptomatic adults were observed in the nearby stream (Scholz et al., unpublished data). The underlying reasons Figure 2. Female coho spawner mortality as a function of the proportion of each of the top three predictors in a given site basin, at the six study sites.Individual points correspond to specific years for each site. Mortality expressed as proportion of all returning females that died in a given year. Solid circle=Des Moines; hollow circle=Fauntleroy; solid square=Fortson; hollow square=Longfellow; solid triangle=Piper’s; hollow triangle=Thornton Creek. doi:10.1371/journal.pone.0023424.g002 Ecotoxicology of Salmon Mortality in Urban Streams PLoS ONE | www.plosone.org 7 August 2011 | Volume 6 | Issue 8 | e23424 North Ridgeview Estates Plat Hearing Examiner Packet Page 89 of 422 for the syndrome’s surprising uniqueness to adult coho are not yet known. Daily or weekly stream surveys are labor intensive, and for this reason only a subset of urban drainages in Puget Sound have been monitored to date. The GIS-based mapping tool developed for this study can be used to focus future monitoring efforts on basins with a higher likelihood of coho die-offs based on land cover attributes. In addition to the basins we have identified within the range of the Puget Sound/Georgia Basin ESU, this approach could be extrapolated to other geographic areas where coho return to spawn along a gradient of urban growth and development. This includes, for example, coho from the Lower Columbia River ESU, a threatened population segment with a spawner range encom- passing the greater metropolitan area of Portland, Oregon. Overall, future surveys will ground-truth initial model outputs and provide additional data that can be used to improve the predictive accuracy of the mapping tool. Our findings have two near-term applications. First, they identify likely ‘‘hotspots’’ for coho spawner mortality throughout central Puget Sound. Given that recurring adult losses at a rate greater than approximately 10% are likely to substantially reduce local population abundances, the high mortality basins in Figure 3 (10–50% and .50% predicted mortality categories) may represent sink habitats for the Puget Sound/Georgia Basin ESU. This is an important consideration for coho recovery planning at the local, county, and regional scales. Second, our results indicate areas where toxic runoff could potentially undermine stream restoration efforts - specifically, strategies that improve physical and biological habitat conditions (flow, connectivity, channel complexity, ripar- ian function, etc.) as a means to boost coho population productivity. The potential influence of rainfall, including timing, frequency, and individual storm intensity, remains an area of active investigation. Throughout the years of stream surveys, it has been qualitatively evident that rainfall influences the mortality syndrome. For example, salmon that arrive and enter a stream during an extended dry interval (a week or more) often survive and then become symptomatic and die when it next rains (Scholz et al., unpublished data). One of our aims in surveying Longfellow Creek (the stream with the most abundant overall returns) for more than a decade was to evaluate inter-annual variation in coho spawner mortality in relation to rainfall. However, a quantitative analysis has proven problematic due to highly variable rainfall patterns in combination with low adult returns in some years. It is clear, however, that the syndrome is not a simple first-flush phenomenon. In most years, both egg retaining and spawned out carcasses were observed across the 8– 10 week fall run, irrespective of the number and size of rain events over that interval. Over the longer term, an approach similar to the one developed here could be used to forecast the likely impacts of future human population growth and development on Puget Sound coho populations that are currently healthy. For example, the expansion of local road networks is a core focus for urban growth planning, and these projections could serve as a basis for evaluating how and where coho spawner mortality will increase under different growth management scenarios. This, in turn, would inform strategies to reduce or mitigate toxic runoff in highly productive basins, in advance of expanding transportation infrastructure – i.e., prevention vs. costly retrofits to the built environment. Also, our modeling approach could be expanded to include the timing and intensity of rainfall as potential drivers for coho spawner mortality. Rainfall patterns may be a key determinant of stormwater quality, although more work in this area is needed. Climate change is expected to shift regional rainfall patterns, and it should be possible to explore how this will interact with changing land cover (urbanization) to influence stormwater quality and toxic runoff to coho spawning habitats. Table 3.Summary of the 95% confidence set (37 of a total of 139 candidate models) of candidate models used to generate map of mortality rates, showing intercepts, estimated coefficients,DAICc and wAICc. Intercept only model included at bottom for reference. Model Equation DAICc wAICc a+b 24.5664+19.76(a)+44.41(b) 0.000 0.0933 c+d+b 23.92152109.56(b)+48.75(c)229.98(d) 0.046 0.0912 c+e+f 23.9355+12.94(c)240.15(e)+38.61(f) 0.372 0.0775 c+d+a 24.4921+12.61(a)+14.03(c)27.54(d) 0.579 0.0698 c+g+a 24.4858+14.31(a)+5.23(c)+3.62(g) 0.669 0.0668 h+a+b 22.6065+15.89(a)+30.87(b)22.38(h) 1.150 0.0525 c+a+b 24.6629+16.37(a)+35.26(b)+2.70(c) 1.357 0.0473 d+a+b 24.7001+17.52(a)+43.83(b)+1.62(d) 1.576 0.0424 c+e 24.5943+19.70(c)253.28(e) 2.425 0.0277 c+d+i+b 23.0628283.44(b)+56.38(c)240.28(d)27.82(i) 2.485 0.0269 c+j+i+b 27.30552130.72(b)+21.23(c)+19.12(i)+10.65(j) 2.543 0.0262 c+d+k+b 23.9266294.52(b)+43.32(c)225.00(d)21.60(k) 2.613 0.0253 j+a+b 24.5174+20.03(a)+43.79(b)20.52(j) 2.752 0.0236 c+d+a+b 24.0864+3.99(a)276.44(b)+38.23(c)223.27(d) 2.885 0.0221 c+d+a+f 24.7368+15.57(a)+16.88(c)29.22(d)222.10(f) 2.925 0.0216 c+d+e+b 23.96072100.49(b)+46.40(c)227.43(d)25.54(e) 2.954 0.0213 c+d+e+f 23.8347+12.37(c)+0.49(d)240.69(e)+39.28(f) 3.280 0.0181 c+g+e+f 23.8534+12.93(c)240.45(e)+38.73(f)20.18(g) 3.294 0.0180 c+j+e+f 23.9360+12.94(c)240.28(e)+39.36(f)20.31(j) 3.326 0.0177 c+g+a+f 24.6143+16.25(a)+5.79(c)213.40(f)+4.06(g) 3.378 0.0172 c+d+i 21.1996+64.26(c)255.97(d)224.83(i) 3.423 0.0168 h+i+b 9.39112153.97(b)217.49(h)+15.89(i) 3.858 0.0136 h+e+f 2.2747227.99(e)+47.38(f)27.31(h) 3.931 0.0131 h+a 1.2512+8.63(a)26.13(h) 4.028 0.0124 c+j+a+b 24.5887+16.71(a)+34.25(b)+2.72(c)20.75(j) 4.299 0.0109 h+k+b 5.8364227.35(b)211.39(h)25.97(k) 4.837 0.0083 c+j+e 24.4356+18.70(c)250.31(e)+1.33(j) 4.915 0.0080 c+j+k+b 22.4511252.30(b)+20.45(c)213.34(j)210.60(k) 4.937 0.0079 c+d+e 24.7362+20.37(c)20.45(d)253.43(e) 5.141 0.0071 c+e+b 24.468021.36(b)+19.52(c)252.48(e) 5.158 0.0071 c+g+e 24.5797+19.68(c)253.23(e)20.02(g) 5.188 0.0070 h+e+b 8.1285220.52(b)245.07(e)214.67(h) 5.509 0.0059 c+k 24.3426+13.30(c)25.31(k) 5.649 0.0055 c+i+b 25.67752141.73(b)+22.77(c)+17.24(i) 5.821 0.0051 c+k+b 23.9708212.84(b)+14.63(c)26.46(k) 5.896 0.0049 h+a+f 0.4930+6.87(a)+19.67(f)25.22(h) 6.083 0.0045 c+d+i+f 21.0499+68.65(c)259.91(d)26.04(f)226.58(i) 6.343 0.0039 Intercept only N/A 20.428 0 Model weights shown here are re-normalized for the set of 37 top-ranked models shown. a=commercial; b=local roads; c=impervious; d=dense urban; e=apartments and condominiums; f=heavily used roads; g=light to medium urban; h=forest; i=residential; j=grass, crops and/or shrubs; and, k=industrial. doi:10.1371/journal.pone.0023424.t003 Ecotoxicology of Salmon Mortality in Urban Streams PLoS ONE | www.plosone.org 8 August 2011 | Volume 6 | Issue 8 | e23424 North Ridgeview Estates Plat Hearing Examiner Packet Page 90 of 422 Ecotoxicology of Salmon Mortality in Urban Streams PLoS ONE | www.plosone.org 9 August 2011 | Volume 6 | Issue 8 | e23424 North Ridgeview Estates Plat Hearing Examiner Packet Page 91 of 422 While not definitive, our results reinforce the parsimonious explanation that coho deaths are caused by one or more contaminants originating from motor vehicles. As noted earlier, this is important because it narrows the list of candidate toxics in complex urban landscapes. Future toxicological studies should focus on two ubiquitous urban runoff contaminant classes in particular. The first are metals in brake pads and other vehicle friction materials. Copper, zinc, and other metals are known to specifically target the fish gill, thereby disrupting respiration and osmoregulation [47]. The second, PAHs, [14,48,49] are taken up across the fish gill, and can impair cardiac function and respiration [50]. The symptoms displayed by affected coho (surface swimming, gaping, loss of equilibrium, etc.) are consistent with a disruption of respiration, osmoregulation, or circulation, or some combination of these. Notably, PAHs and metals usually cause the above toxicological effects at concentrations well above those typically detected in urban streams. However, the majority of conventional toxicology studies using salmonids focus on freshwater species (e.g., rainbow trout) or the freshwater life stages of juvenile anadromous species. There are practically no toxicity data for coho salmon at the adult spawner stage. Many important osmoregulatory changes take place during the transition from seawater prior to spawning, and these may render adult coho more vulnerable to metals and PAHs than freshwater-resident salmonids. Adding to this complexity is the possibility of interactive toxicity (e.g., synergism) among contaminant mixtures. Studies that experimentally reproduce the familiar symptomology and mortality in adult coho, under controlled exposure conditions with environmentally realistic mixtures of metals and PAHs, will likely be necessary to definitively implicate motor vehicles. Acknowledgments We thank John Williams and an anonymous reviewer for significantly improving previous drafts of this manuscript. Disclaimer: the findings, conclusions and views expressed herein are those of the authors and do not necessarily represent those of the National Oceanic and Atmospheric Administration or the U.S. Fish and Wildlife Service. Author Contributions Conceived and designed the experiments: BEF JWD NLS. Performed the experiments: BEF ERB PA. Analyzed the data: BEF ERB PA. Wrote the paper: BEF ERB NLS. References 1. Weinstein MP, Baird RC, Conover DO, Gross M, Keulartz J, et al. (2007) Managing coastal resources in the 21st century. Frontiers in Ecology and the Environment 5: 43–48. 2. Interagency Ocean Policy Task Force (2010) Final Recommendations of the Interagency Ocean Policy Task Force. Washington, DC: The White House Council on Environmental Quality. 96 p. 3. Pew Oceans Commission (2003) America’s Living Oceans: Charting a Course for Sea Change. Arlington, Virginia: Pew Charitable Trusts. 166 p. 4. 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Alberti M, Weeks R, Coe S (2004) Urban land-cover change analysis in Central Puget Sound. Photogrammetric Engineering and Remote Sensing 70: 1043–1052. 24. Alberti M, Weeks R, Hepsintall J, Russell C, Coe S, et al. (2004) Puget Sound Regional Synthesis Model: 2002 Land-cover Analysis of the Greater Puget Sound Region. Seattle, WA: University of Washington. 26 p. 25. Homer C, Huang C, Yang L, Wylie B, Coan M (2004) Development of a 2001 National Landcover Database for the United States. Photogrammetric Engineering and Remote Sensing 70: 829–840. 26. King County (2000) King County Tax Parcels. CD-ROM. Seattle, WA: King County. 27. Kitsap County (2010) Land Information System (LIS): Tax Parcels. Figure 3. Predictive map of modeled coho spawner mortality rates within the Puget Sound lowlands.Mortality rates are a function of the proportion of key landscape variables within a given basin. Green, yellow and red areas indicate basins with predicted rates of spawner mortality (as a percentage of total fall runs) of ,10%, 10–50%, and .50%, respectively. Black dots denote locations of the six study sites that were the basis for this analysis. Thick dashed black line depicts the southern boundary of the coho salmon Puget Sound/Georgia Basin Evolutionarily Significant Unit (ESU). Basins that do not have documented presence of coho salmon [38] are not represented on the map, even if they have landscape conditions associated with coho spawner mortality. Key for site numbers: 1=Des Moines; 2=Fauntleroy; 3=Fortson; 4=Longfellow; 5=Piper’s; and, 6=Thornton Creek. doi:10.1371/journal.pone.0023424.g003 Ecotoxicology of Salmon Mortality in Urban Streams PLoS ONE | www.plosone.org 10 August 2011 | Volume 6 | Issue 8 | e23424 North Ridgeview Estates Plat Hearing Examiner Packet Page 92 of 422 28. Pierce County (2008) Tax Parcels. Tacoma, WA: Pierce County Assessor- Treasurer. 29. Snohomish County (2010) Parcels Snohomish County Assessor. 30. Puget Sound Regional Council (2005) Road centerlines and widths. Available: http://www.psrc.org. Accessed: 2005 Aug 16. 31. Federal Highway Administration (1989) Functional Classification Guidelines U.S. Department of Transportation. 34 p. 32. Bolker BM, Brooks ME, Clark CJ, Geange SW, Poulsen JR, et al. (2009) Generalized linear mixed models: a practical guide for ecology and evolution. Trends in Ecology & Evolution 24: 127–135. 33. Gelman A, Hill J (2007) Data analysis using regression and multilevel/ hierarchical models. New York, NY: Cambridge University Press. 648 p. 34. Pinheiro JC, Bates DM (2001) Mixed-effects models in S and S-PLUS; Chambers J, Eddy W, Hardle W, Sheather S, Tierney L, eds. New York, NY: Springer Verlag. 528 p. 35. R Development Core Team (2010) R: A language and environment for statistical computing. 2.12.0 ed. Vienna, Austria: The R Development Core Team. 36. Burnham KP, Anderson DR (2002) Model selection and multimodel inference: A practical information theoretic approach. New York, NY: Springer-Verlag. 488 p. 37. U.S. Environmental Protection Agency, U.S. Geological Survey (2005) National Hydrography Dataset Plus – NHDPlus. Available: http://www.horizon-systems. com/NHDPlus/HSC-wth17.php. Accessed: 2010 May 26. 38. Washington Department of Fish and Wildlife (2011) 1:24,000 Fish Distribution of Washington State: Washington Lakes and Rivers Information System (WLRIS) - fishdist. February 2011 ed. Olympia, WA: Washington Department of Fish and Wildlife. 39. Karr JR (1991) Biological Integrity: A Long-Neglected Aspect of Water Resource Management. Ecological Applications 1: 66–84. 40. Alberti M, Booth D, Hill K, Coburn B, Avolio C, et al. (2007) The impact of urban patterns on aquatic ecosystems: An empirical analysis in Puget lowland sub-basins. Landscape and Urban Planning 80: 345–361. 41. Wenger SJ, Roy AH, Jackson CR, Bernhardt ES, Carter TL, et al. (2009) Twenty-six key research questions in urban stream ecology: an assessment of the state of the science. Journal of the North American Benthological Society 28: 1080–1098. 42. Morley SA, Karr JR (2002) Assessing and restoring the health of urban streams in the Puget Sound basin. Conservation Biology 16: 1498–1509. 43. Bilby RE, Mollot LA (2008) Effect of changing land use patterns on the distribution of coho salmon (Oncorhynchus kisutch) in the Puget Sound region. Canadian Journal of Fisheries and Aquatic Sciences 65: 2138–2148. 44. Feist BE, Steel EA, Jensen DW, Sather DND (2010) Does the scale of our observational window affect our conclusions about correlations between endangered salmon populations and their habitat? Landscape Ecology 25: 727–743. 45. Committee on Protection and Management of Pacific Northwest Anadromous Salmonids, National Research Council (1996) Habitat Management and Rehabilitation. Upstream: Salmon and Society in the Pacific Northwest. Washington, DC: National Academy Press. pp 204–225. 46. Katz SL, Barnas K, Hicks R, Cowen J, Jenkinson R (2007) Freshwater Habitat Restoration Actions in the Pacific Northwest: A Decade’s Investment in Habitat Improvement. Restoration Ecology 15: 494–505. 47. Niyogi S, Wood CM (2004) Biotic Ligand Model, a Flexible Tool for Developing Site-Specific Water Quality Guidelines for Metals. Environmental Science & Technology 38: 6177–6192. 48. Hoffman EJ, Latimer JS, Mills GL, Quinn JG (1982) Petroleum hydrocarbons in urban runoff from a commercial land use area. Journal Water Pollution Control Federation 54: 1517–1525. 49. Whipple W, Hunter JV (1979) Petroleum hydrocarbons in urban runoff. Journal of the American Water Resources Association 15: 1096–1105. 50. Claireaux G, Davoodi F (2010) Effect of exposure to petroleum hydrocarbons upon cardio-respiratory function in the common sole (Solea solea). Aquatic Toxicology 98: 113–119. 51. McMillan B (2007) The Spawning Survey Findings from Seattle’s Thornton, Piper’s, Longfellow, Fauntleroy and Taylor Creeks, September 21, 2006 to January 24, 2007. Also including the cumulative spawning survey data from 1999–2006 and Des Moines Creek in 2003 and 2004. Seattle, Washington, USA: Seattle Public Utilities. 52. Wild Fish Conservancy (2008) Spawning Survey Findings from Seattle’s Thornton, Piper’s, Longfellow, Fauntleroy and Taylor Creeks. Seattle, Washington, USA: Seattle Public Utilities. Ecotoxicology of Salmon Mortality in Urban Streams PLoS ONE | www.plosone.org 11 August 2011 | Volume 6 | Issue 8 | e23424 North Ridgeview Estates Plat Hearing Examiner Packet Page 93 of 422 December 17, 2017 City of Auburn Jeff Tate, Assistant Director Community Development & Public Works Department 25 West Main Street Auburn WA 98001 RE: Comments and Concerns regarding development plans for north Ridgeview Estates 30 -lot plat (SEP 17-0001) Mr. Tate: As an immediate neighbor to the north of the proposed North Ridgeview Estates Development I believe the plans I have been able to review do not address a number of environmental and long term area growth concerns adequately. Below are a list of concerns, suggestions and additional questi ons that we would like answered. Site Water and Soil concerns: This development’s position on the hillside with unusual soil types and layers makes it difficult to work without affecting the hydrology of the entire area and in particular the properties just to the north which are in a valley. Any additional water flowing or directed across the surface of adjacent properties from this development would make them wetter and less useable. This is an unacceptable significant impact to us and needs to be mitigated as part of the development plan. The documents indicate water seepage or lateral movement caused by hardpan layers under the soil exists and it would be reasonable to assume the development and elimination of existing plants and permeable surface will create more erosion and change water drainage to the properties to the north. Studies and reports submitted with plans have conflicting ideas on hydrology related to landslides, ground water tables, and onsite infiltration. One study says some areas are not suited for it and other areas are susceptible to lateral groundwater movement causing seepage. The plans call for infiltration? Would infiltration increase potential of a landslide? What if there was an earthquake? Why did King County list it on their maps as a seismic and erosion and landslide risk? The site already has areas in which seepage is evident and there is wetness coming out of the hill (and probably a perched water table). (Look at the aerial photo and you can see the green areas and the change of grass type at the base of the hill on the northern side from the east all the way to the west side!) As recently as last June 2017 the City of Kent drained their water tank at the top of the hill on to the ground on the top of the hill where it immediately soaked in, but within hours it seeped out the bottom of the hill across the base! A frantic situation of thousands of gallons of water suddenly appearing at the base of the hill had property owners such as myself downstream concerned about a ruptured failing water tank or piping. It was difficult to walk through or use the affected areas, which were inundated with the runoff. This North Ridgeview Estates Plat Hearing Examiner Packet Page 94 of 422 effectively tested the hydrology of the hill and demonstrated how fast water will flow through the soil on this hill and how little really is absorbed into the ground. Any hard surface that concentrates rain or water into infiltration systems (especially closer) to the low side of the hill will increase water seeping out of the hill at the base and surface water flowing across other properties to get to the creek. Provisions for draining the Kent Water tank need to be addressed along with this plan. Site construction plans needs to control any soil erosion and keep silt and clay out of the creek and adjoining properties. Will wheel washing equipment and street sweeping be implemented as well as silt filters in the drainage ditch to control dirt? Will traffic in and out of the dirt construction area be minimized to reduce vehicle dirt tracking onto the street which drains immediately into Westside Suzette Creek. Grading and movement of soil types needs to be considered as fine soils over the top of coarse soils will reduce the permeability of the coarse soils and increase surface water to run off on neighboring properties. 124th safety improvements are needed in this area. There are no sidewalks or streetlights and there is a troubling intersection at 284th St with a lot of accidents. In the future, a planned street extension of 284th to 132nd will be difficult after this development. The new street is likely to cause a 2nd difficult intersection, are there any plans to address this? Most of the parcels along the north edge of this development are landlocked with no effective access for development because of the creek. Access to streets from this development should be considered to minimize disturbance to sensitive areas from future development of these parcels. Plantings in wetlands and open space should be carefully considered to minimize future winter shadows and blocking Mt Rainier views. Please limit or do not plant Douglass firs or Cedars. Vine maples, dog woods, spirea and ocean spray are some great native plants that could be used. Aesthetics of detention pond - It would be best if it looked and functioned somewhat naturally… a pond / small lake could be dug to naturally filter and meter outflow to the creek at the north side. Please try to avoid the industrial look of a treatment pond. Trails should allow for walking and some equestrian use in the open space. I have a few more questions as well. Church/ temple parking along 124th- is it solved? Use of open space- is it public? Traffic to 132nd- how does that happen? It is not safe to walk along 124th, can a trail be made that is separated from the street to enhance pedestrian safety? A young man was killed walking along 124th within 400 feet of this proposed development. North Ridgeview Estates Plat Hearing Examiner Packet Page 95 of 422 Street lighting/and general lighting needs to minimize light pollution. You can still see stars in this area of Auburn Most important is not water in the creek flowing through our property but how the water gets to the creek from the development. Thank you for taking the time to read through my concerns, I look forward to your response. Ed Blechen 12641 SE 282nd St. Auburn, Wa. North Ridgeview Estates Plat Hearing Examiner Packet Page 96 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 97 of 422 -This page left intentionally blank- North Ridgeview Estates Plat Hearing Examiner Packet Page 98 of 422 EXHIBIT 6 PRELIMINARY CIVIL PLANS, PREPARED BY BARGHAUSEN CONSULTING ENGINEERS, 11/2/2017 FULL-SIZE COPIES OF THE PELIMINARY CIVIL PLANS ARE AVAILABLE TO THE PUBLIC AT THE AUBURN CITY CLERK'S OFFICE. 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North Ridgeview Estates Plat Hearing Examiner Packet Page 121 of 422 -This page left intentionally blank- North Ridgeview Estates Plat Hearing Examiner Packet Page 122 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 123 of 422 1 TRAFFIC IMPACT ASSESSMENT NORTH RIDGEVIEW ESTATES AUBURN, WASHINGTON Introduction/Executive Summary The purpose of this (revised) assessment is to briefly summarize the traffic-related impacts associated with the development of a single-family residential subdivision, i.e., North Ridgeview Estates, and respond to Staff comments. This assessment provides an analysis of the project based on discussions with the Applicant’s representative (Jeff Potter, Integrity Land, LLC, 425-432-2655) and comments provided by City Staff, including an analysis of the future operation of the site access at 124th Avenue SE and the nearby intersection of SE 284th Street/124th Avenue SE. Specifically, the analysis includes the following items/assumptions in its scope of work: • An analysis of the development of a 30-lot single-family residential subdivision. • Development of the project is assumed completed in 2021. • Trip generation for the project used data from the most current edition of the ITE Trip Generation manual. • Two intersections (SE 284th Street/124th Avenue SE and the Site Access/124th Avenue SE) were analyzed for existing and future operating conditions. • Collision history adjacent to the site was reviewed. The proposed development is located on the east side of 124th Avenue SE in the SE 28400 block in the City of Auburn. The parcel is just shy of 30 acres in size and currently is undeveloped. The proposed action would develop 30 single-family residential lots and include a large open space tract. The proposed project could generate approximately 286 new daily trips, 23 of which would occur during the AM peak hour and 30 during the PM peak hour. Sole access to the site is proposed from a new access street extending easterly from 124th Avenue SE. The street will stub into the property to the east for a future extension to 132nd Avenue SE. Specific details on the project and the analysis of its impacts can be found in the subsequent sections. In general, the project will have a small impact on the transportation system. The payment of traffic impact fees will mitigate the project’s impacts on the transportation system. North Ridgeview Estates Plat Hearing Examiner Packet Page 124 of 422 2 Background/Project Description The proposed project is for the development of 30 single-family residential lots. The project site is located on the east side of 124th Avenue SE in the City of Auburn. Sole access to the site is proposed from 124th Avenue SE at approximately SE 286th Street. This access road would extend east/southeasterly curving through the subdivision and stubbing into the property to the east at approximately SE 288th Street, if extended, with a future connection (by others) to 132nd Avenue SE. Currently, the property is a gently rolling, undeveloped 30-acre parcel that is mostly pastureland with some coniferous and deciduous trees and brush along the perimeters. The surrounding land consists of a mix of undeveloped parcels and single-family residences, with the high school, a water tower and place of worship in close proximity to the site. The parcel is currently zoned “R-1/Urban Separator Overlay” which allows the proposed use. A vicinity map of the area is shown on Figure 1 and a preliminary site plan for the project has been attached. Roadways/Non-Motorized Facilities/Transit The following describe the roadways and existing conditions in the project vicinity. 124th Avenue SE is a north-south minor arterial that provides a connection to Kent- Kangley Road to the north and SE 320th Street to the south. The roadway consists of one through lane in each direction and 6-foot wide paved shoulders in the vicinity of the project. Curb, gutter, sidewalk and street lights have been installed along the frontages of more recent development to the south and turn storage lanes have been installed at major intersections. A roundabout controls the SE 304th Street/124th Avenue SE intersection. The posted speed is 35-mph and the adjacent land use is a mix of single-family residences, schools, and large lot/ undeveloped parcels. As noted in the previous section, sidewalk has been constructed along sections of 124th Avenue SE where new development has occurred. Wide, paved shoulders are also provided along many sections of the roadways which can be used by both pedestrians and bicyclists. Metro Transit is responsible for providing transit in King County. Currently, route #164 travels along 124th Avenue SE and serves Green River Community College and the Kent Transit Station, and also provides service along Kent-Kangley Road. Service is provided weekdays between approximately 6:00 AM and 11:00 PM at 30- to 60-minute headways, with slightly less frequency on Saturdays. No Sunday North Ridgeview Estates Plat Hearing Examiner Packet Page 125 of 422 3 service is currently provided. Transit stops are currently provided to the south near the high school and to the north in the vicinity of SE 282nd Street. Collision History Traffic collision data for 124th Avenue SE along the project frontage and at the SE 284th Street/124th Avenue SE intersection were acquired from the City of Auburn (Amber Price). The collision data are from January 2014 through December of 2016. The following table summarizes the accident frequency and severity for this period. TABLE 1 COLLISION HISTORY – 124TH AVENUE SE (REVISED) Location/Date Accident Type Total Property Damage Injury Fatality At SE 284th Street 2014 3 2 0 5 2015 2 3 0 5 2016 2 2 0 4 Between SE 284th & SE 286th Place 2014 1 2 0 3 2015 0 0 0 0 2016 0 0 0 0 The collision data shows that the SE 284th Street/124th Avenue intersection typically averages four to five collisions per year and the section of 124th Avenue between SE 284th Street and SE 286th Place typically averages one collision per year. Rear-end, right angle, and head-on collisions were the predominant collision type. Roadway Improvement Projects The City of Auburn currently has one project listed in the 2017-2022 Six Year Transportation Improvement Plan (TIP) within close proximity to the project site. Project #45 notes capacity and safety design improvement plans for the SE 284th Street/124th Avenue SE intersection. Additionally, the SE 284th/SE 288th Street collector that would provide a connection between 124th Avenue SE and 132nd Avenue SE is a City project noted in the Comprehensive Transportation Plan for the 2035 analysis. The roadway would be one lane in each direction with bike lanes and sidewalks. The construction of the subdivision’s internal access is intended to serve as a portion of this future connection to 132nd Avenue SE. North Ridgeview Estates Plat Hearing Examiner Packet Page 126 of 422 4 Trip Generation/Assignment The proposed residential subdivision would generate new traffic onto the adjacent street system. The trip generation for the project has been estimated using the most recent values found in the ITE Trip Generation manual (published by the Institute of Transportation Engineers, 2012, 9th Edition). Based on the proposed use and the land use descriptions provided in the Trip Generation manual, Land Use Code 210 – Single-Family Detached Housing best represents the proposed use. Table 2 summarizes the total trip generation associated with the proposed use, using the average trip rates and number of lots as the independent variable. TABLE 2 ESTIMATED WEEKDAY TRIP GENERATION NORTH RIDGEVIEW ESTATES Unit of Measure Trip Rate Daily/AM Peak/ PM Peak Daily Trips Peak Hour Trips AM In/Out (Total) PM In/Out (Total) 30 Single-Family Dwelling Units 9.52/0.75/1.00 trips per dwelling unit 286 6/17 (23) 19/11 (30) Table 2 shows that the number of new trips associated with the subdivision will be relatively small, with just the PM peak hour generating 30 peak hour trips and would not impact any off-site intersections requiring analysis other than the site access. The new traffic generated by the project will be distributed onto the adjacent arterials, primarily 124th Avenue SE, which provides access to the north to Kent- Kangley Road (to shopping and employment opportunities) and to the south to SR-18 via SE 304th Street. Further to the south, 124th provides access to Green River Community College and Lea Hill Road, which provides access to downtown Auburn. Convenient access to SR-18 provides quick travel time to shopping and employment centers to the west/southwest. As such, the site- generated traffic has been assigned accordingly to the north, south, and west to reflect the likely destinations of the future residents and the available transportation facilities. Figure 2 shows the generalized trip distribution for the site by percent, along with the AM and PM peak hour trip assignment. This distribution is based on an examination of the street system, and (as noted above) the surrounding employment and shopping destinations. Approximately 50% of the site traffic has been distributed to the north and 50% to the south, with further distribution at SE 284th Street and SE 304th Street. Overall, the project will have very limited North Ridgeview Estates Plat Hearing Examiner Packet Page 127 of 422 5 impacts on the adjacent arterials during either of the peak hours, with just the site access impacted by 30 trips during the PM peak hour. Traffic Volumes AM and PM peak hour traffic counts for the SE 284th Street/124th Avenue SE intersection were available from the City of Auburn for use in this assessment. These counts were conducted in March of 2016 and are summarized on Figure 3. Also included on Figure 3 are the 2021 projected volumes, with and without the project. The future volumes include a 4% annual growth rate to account for miscellaneous background traffic. City Staff indicated that no pipeline trips of significance in the area needed to be included in the future volumes. Historical traffic count data along 124th Avenue SE was reviewed to determine an appropriate annual growth rate. The 2015 volumes were just shy of the values recorded in 2006 (a negative growth rate). The 7-year growth rate was about 3%, the 6-year rate was about 5.5%, and the 2-year rate about 3.5%. As such, a 4% annual rate was deemed a reasonable value for the 2021 projections. Furthermore, a nominal number of trips at the site access are included for the “with project” condition to account for the re-assignment of miscellaneous trips through the subdivision for the adjacent 5400 square-foot place of worship. (Note: two inbound/one outbound AM peak hour trips and one inbound/two outbound PM peak hour trips per ITE Land Use 560 – Church were used for the re-assignment of trips associated with this 5400 square foot structure.) Appendix A-1 provides a summary table of the existing, future and project trips for the AM and PM peak hours at the SE 284th Street/124th Avenue SE intersection and the future volumes at the site access. Level of Service Capacity analyses for the AM and PM peak hours were conducted at the SE 284th Street/124th Avenue SE intersection and at the intersection of the site access with 124th Avenue SE in order to determine the current level of service and the likely future operating conditions upon completion of the subdivision. The intersection of SE 284th Street/124th Avenue SE is stop-controlled in the eastbound direction with one-lane approaches. The site access will be stop-controlled in the westbound direction with one-lane approaches. “Level of service” (LOS) is a common term used in the Traffic Engineering profession that is defined as a qualitative measure describing operational conditions within a traffic stream, and its perception by motorists and/or passengers. These conditions are usually described in terms of such factors as speed and travel time, freedom to maneuver, traffic interruptions, comfort and convenience, and safety. Six levels of service are designated, ranging from “A” to “F”, with level of service “A” representing the best operating conditions and level North Ridgeview Estates Plat Hearing Examiner Packet Page 128 of 422 6 of service “F” the worst. The City of Auburn uses corridor level-of service for its arterials, with LOS “D” typically the standard with the exception of some corridors that may operate at LOS “E” or “F”. The level-of service standard for individual two-way stop controlled and all-way stop controlled intersections is LOS “D”. The level of service was determined using procedures/methodologies described in the 2010 Highway Capacity Manual (HCM) and the “Synchro 8” software. The following table shows the current levels of service for the intersections using the traffic volumes shown on Figure 3. Calculations for the level of service analyses have been attached. (Note: per e-mail correspondence with City Staff, a northbound left-turn lane was included in the future conditions at SE 284th Street/ 124th Avenue SE to reflect probable improvements that could occur at the intersection as part of the City improvement project in 2020.) TABLE 3 PEAK HOUR LEVELS OF SERVICE (REVISED) AM - SE 284th St./ 124th Ave. SE Northbound Southbound Eastbound Westbound Existing LOS A 8.6 sec. N.A. LOS C 15.9 sec. N.A. Future (2021) w/out project* LOS A 9.0 sec. N.A. LOS C 20.8 sec. N.A. Future (2021) with project* LOS A 9.0 sec. N.A. LOS C 21.1 sec. N.A. PM - SE 284th St./ 124th Ave. SE Existing LOS A 8.3 sec. N.A. LOS C 16.6 sec. N.A. Future (2021) w/out project* LOS A 8.6 sec. N.A. LOS C 22.8 sec. N.A. Future (2021) with project* LOS A 8.6 sec. N.A. LOS C 23.5 sec. N.A. AM – Site Access/ 124th Ave. SE Future (2021) with project N.A. LOS A 8.3 sec. N.A. LOS C 16.2 sec. PM – Site Access/ 124th Ave. SE Future (2021) with project N.A. LOS A 8.3 sec. N.A. LOS C 15.6 sec. N.A. – not applicable (i.e., calculation not provided for specific analysis, not a critical movement, or no volume on subject movement) *- future conditions include the addition of a northbound left-turn lane North Ridgeview Estates Plat Hearing Examiner Packet Page 129 of 422 7 Where: LOS Delay – Unsignalized A < 10 seconds B > 10 & < 15 seconds C > 15 & < 25 seconds D > 25 & < 35 seconds E > 35 & < 50 seconds F > 50 seconds Table 3 shows the level of service results for the AM and PM peak hours. The eastbound stop-controlled movement at SE 284th Street/124th Avenue SE intersection is currently operating at level of service “C” during both peak hours. Level of service “C” will continue to be present during both peak hours upon completion of the project. The increases in delay on the eastbound stop controlled movement would be less than one second with the additional project trips through the intersection. (Note: the project would impact this intersection with less than 30 peak hour trips; the analysis of this intersection was included in this assessment per Staff comments.) The westbound stop-controlled movement for the site access is projected at level of service “C” during both peak hours. These levels of service are considered acceptable. Project Impacts The development of the North Ridgeview Estates subdivision could potentially generate just under 300 trips per day with 23 of these trips during the AM peak and 30 PM peak hour trips on a typical weekday. Access to the site is proposed from 124th Avenue SE at a new intersection at approximately SE 286th Street. Off- site traffic-related impacts from the project will be nominal. The adjacent arterial (124th Avenue SE) is a two-lane roadway with paved shoulders present near the project site; curb, gutter and sidewalk have been installed along the frontages of new development to the south and turn storage lanes are installed at major intersections. The results of the capacity analyses for the future conditions show minor increases in delay from the existing conditions. The following summarizes the current and future conditions at the intersection of SE 284th Street/124th Avenue SE and the future site access. • SE 284th Street/124th Avenue SE – the eastbound movement at this stop-controlled “T-intersection” is currently operating at level of service “C” during both peak hours. Level of service “C” will continue to be present upon completion of the project during both the AM and PM peak hours. The project trips will increase delay on the eastbound movement 0.3 and 0.7 seconds during the AM and PM peak hours, respectively, and impact the intersection with 14 or fewer trips during North Ridgeview Estates Plat Hearing Examiner Packet Page 130 of 422 8 either peak hour. No mitigation is needed nor recommended for this location. • Site Access/124th Avenue SE – this new intersection with 124th Avenue SE will serve as the sole access for the subdivision. The street will extend east/ southeasterly curving through the subdivision and stub into the property to the east at approximately SE 288th Street, if extended, with a future connection (by others) to 132nd Avenue SE. Level of service “C” is projected for the stop-controlled westbound movement during both peak hours. The number of left-turns from 124th Avenue SE into the site is not of a magnitude that would require turn storage. Conclusions/Recommendations The development of the North Ridgeview Estates subdivision will generate additional traffic onto the existing transportation system and will involve the payment of a transportation impact fee for roadway improvement projects per the City of Auburn’s requirements. No mitigation other than the payment of impact fees is recommended for the project. North Ridgeview Estates Plat Hearing Examiner Packet Page 131 of 422 9 Attachments North Ridgeview Estates Plat Hearing Examiner Packet Page 132 of 422 1 APPENDIX A-1 SUMMARY OF PEAK HOUR VOLUMES 1.SE 284th Street/124th Avenue SE - AM peak hour EBL EBT EBR WBL WBT WBR NBL NBT NBR SBL SBT SBR TEV Existing volumes 26 0 58 0 0 0 76 269 0 0 349 30 808 2021 volumes with 4% annual growth 32 0 71 0 0 0 92 327 0 0 425 37 984 Project trips 0 0 0 0 0 0 1 7 0 0 3 0 11 2021 volumes with project 32 0 71 0 0 0 93 334 0 0 428 37 995 1.SE 284th Street/124th Avenue SE - PM peak hour EBL EBT EBR WBL WBT WBR NBL NBT NBR SBL SBT SBR TEV Existing volumes 63 0 82 0 0 0 49 276 0 0 321 54 845 2021 volumes with 4% annual growth 77 0 100 0 0 0 60 336 0 0 390 66 1029 Project trips 0 0 1 0 0 0 1 4 0 0 8 0 14 2021 volumes with project 77 0 101 0 0 0 61 340 0 0 398 66 1043 2.Site Access/124th Avenue SE - AM peak hour EBL EBT EBR WBL WBT WBR NBL NBT NBR SBL SBT SBR TEV Existing volumes 0 0 0 0 0 0 0 345 0 0 407 0 752 2021 volumes with 4% annual growth 0 0 0 0 0 0 0 420 0 0 495 0 915 Project trips 0 0 0 9 0 8 0 0 3 3 0 0 23 Other (1) 0 0 0 1 0 0 0 0 1 1 0 0 3 2021 volumes with project 0 0 0 10 0 8 0 420 4 4 495 0 941 (1)- trips associated with revised access for 5400 SF Gurudwara Sacha Marg Sahib per ITE Land Use 560 2.Site Access/124th Avenue SE - PM peak hour EBL EBT EBR WBL WBT WBR NBL NBT NBR SBL SBT SBR TEV Existing volumes 0 0 0 0 0 0 0 325 0 0 403 0 728 2021 volumes with 4% annual growth 0 0 0 0 0 0 0 395 0 0 490 0 885 Project trips 0 0 0 6 0 5 0 0 10 9 0 0 30 Other (1) 0 0 0 1 0 1 0 0 1 0 0 0 3 2021 volumes with project 0 0 0 7 0 6 0 395 11 9 490 0 918 (1)- trips associated with revised access for 5400 SF Gurudwara Sacha Marg Sahib per ITE Land Use 560 North Ridgeview Estates Plat Hearing Examiner Packet Page 133 of 422 -This page left intentionally blank- North Ridgeview Estates Plat Hearing Examiner Packet Page 134 of 422 EXHIBIT 8 SCHOOL ACCESS ANALYSIS North Ridgeview Estates Plat Hearing Examiner Packet Page 135 of 422 -This page left intentionally blank- North Ridgeview Estates Plat Hearing Examiner Packet Page 136 of 422 REVISED North Ridgeview Preliminary Plat Application Auburn, WA Parcels: 332205-9103, -9115, and -9154 Schools Access Analysis: This project is unique in the fact that the homes will reside within the City of Auburn, but also lie within the Kent School District. Currently the majority of the homes are within the Pine Tree Elementary School boundary with a smaller portion of the homes being within the Horizon Elementary School boundary. The same goes for Middle School with the majority attending Mattson Middle School and a smaller portion falling within the Cedar Heights Middle School Boundary. The whole site is within the Kentlake High School Boundary. After speaking with Kelly Bissell at the Kent School District Transportation Office on March 14, 2017 we were able to determine that a bus stop will be re-established at the intersection of 124th Ave SE & SE 286th Pl or at our new plat entrance once it has been built. This was a bus stop that has been used in the past but is not currently being used. All students from within North Ridgeview would ride the bus to their prospective school (elementary, middle or high) from this bus stop. Although this site technically falls within the “not eligible to ride bus” threshold, the Kent School District has set up a bus stop as there is not a safe path of travel for students to walk to Pine Tree Elementary School from our location. Attached please find an email from Kelly Bissell which lays out the bus stop location. As school boundaries can change yearly and the Kent School District is in the process of building a new elementary school, the schools in which these students would attend could change, but the bus stop location will remain the same. Assuming a site address of 12431 SE 286TH PL (which is the address for the neighboring church and as close as possible to the new entrance to the plat) here are the following distances to each of the schools: •Pine Tree Elementary School – 0.9 miles via SE 284th St or 1.1 miles via 124th Ave SE 27825 118th Ave SE, Kent, WA •Horizon Elementary School – 3.0 miles via WA-516 or 2.7 miles via SE 288th St 27641 144th Ave SE, Kent, WA •Mattson Middle School – 4.9 miles via SE 256th St or 5.4 miles via WA-516 16400 SE 251st St, Covington, WA •Cedar Heights Middle School – 6.0 miles via WA-516 or 7.5 miles via SE 256th St or 7.0 miles via WA-18 E 19640 SE 272nd St, Covington, WA North Ridgeview Estates Plat Hearing Examiner Packet Page 137 of 422 •Kentlake High School – 8.8 miles via SE Covington Sawyer Rd, 9.4 miles via WA- 516 or 9.8 miles via 152nd Ave SE. 21401 SE Falcon Way, Kent, WA Maps with driving route and distance for each school are attached. Per the Kent School District: (also attached for reference) Eligibility to Ride a Bus: The transportation department determines bus stops following guidelines and laws pertinent to safety and hazardous conditions in compliance with Kent School District’s Policy #6600, Washington Administrative codes, and Revised Codes of Washington (RCW). Maximum walking distances are: Elementary •K - 6 - 1 1/3 miles Secondary •Middle School - 1 3/4 miles •Senior high - 2 miles North Ridgeview Estates Plat Hearing Examiner Packet Page 138 of 422 North Ridgeview Estates PlatHearing Examiner Packet Page 139 of 422 North Ridgeview Estates PlatHearing Examiner Packet Page 140 of 422 North Ridgeview Estates PlatHearing Examiner Packet Page 141 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 142 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 143 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 144 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 145 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 146 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 147 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 148 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 149 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 150 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 151 of 422 -This page left intentionally blank- North Ridgeview Estates Plat Hearing Examiner Packet Page 152 of 422 EXHIBIT 9 GEOTECHNICAL REPORT AND COMMENT RESPONSES, PREPARED BY EARTH SOLUTIONS NW, MULTIPLE PREPARE DATES North Ridgeview Estates Plat Hearing Examiner Packet Page 153 of 422 -This page left intentionally blank- North Ridgeview Estates Plat Hearing Examiner Packet Page 154 of 422 EarthSolutionsNWLLC EarthSolutions NW LLC Geotechnical Engineering Geology Environmental Scientists Construction Monitoring 1805 -136th Place N.E.,Suite 201 Bellevue,WA 98005 (425)449-4704 Fax (425)449-4711 www.earthsolutionsnw.com GEOTECHNICAL ENGINEERING STUDY RIDGEVIEW ESTATES 124XX -124th AVENUE SOUTHEAST KING COUNTY (AUBURN), WASHINGTON ES-4572 North Ridgeview Estates Plat Hearing Examiner Packet Page 155 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 156 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 157 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 158 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 159 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 160 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 161 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 162 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 163 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 164 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 165 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 166 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 167 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 168 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 169 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 170 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 171 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 172 of 422 Drwn. Checked Date Date Proj.No. Plate Earth Solutions NWLLC Geotechnical Engineering,Construction Monitoring EarthSolutionsNWLLC EarthSolutions NW LLC and Environmental Sciences Vicinity Map Ridgeview Estates Auburn,Washington MRS AZS 07/11/2016 July 2016 4572 1 NORTH NOTE:This plate may contain areas of color.ESNW cannot be responsible for any subsequent misinterpretation of the information resulting from black &white reproductions of this plate. Reference: King County,Washington Map 716 By The Thomas Guide Rand McNally 32nd Edition SITE North Ridgeview Estates Plat Hearing Examiner Packet Page 173 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 174 of 422 Drwn. Checked Date Date Proj.No. Plate Earth Solutions NWLLC Geotechnical Engineering,Construction Monitoring and Environmental Sciences EarthSolutionsNWLLC EarthSolutions NW LLC RETAINING WALL DRAINAGE DETAIL NOTES: Free Draining Backfill should consist of soil having less than 5 percent fines. Percent passing #4 should be 25 to 75 percent. Sheet Drain may be feasible in lieu of Free Draining Backfill,per ESNW recommendations. Drain Pipe should consist of perforated, rigid PVC Pipe surrounded with 1" Drain Rock. LEGEND: Free Draining Structural Backfill 1 inch Drain Rock 18"Min. Structural Fill Perforated Drain Pipe (Surround In Drain Rock) SCHEMATIC ONLY -NOT TO SCALE NOT A CONSTRUCTION DRAWING Ridgeview Estates Auburn,Washington GLS 07/28/2016 4572 AZS July 2016 3 North Ridgeview Estates Plat Hearing Examiner Packet Page 175 of 422 Drwn. Checked Date Date Proj.No. Plate Earth Solutions NWLLC Geotechnical Engineering,Construction Monitoring and Environmental Sciences EarthSolutionsNWLLC EarthSolutions NW LLC FOOTING DRAIN DETAIL Slope Perforated Rigid Drain Pipe (Surround with 1"Rock) 18"(Min.) NOTES: Do NOT tie roof downspouts to Footing Drain. Surface Seal to consist of 12"of less permeable,suitable soil.Slope away from building. LEGEND: Surface Seal;native soil or other low permeability material. 1"Drain Rock SCHEMATIC ONLY -NOT TO SCALE NOT A CONSTRUCTION DRAW ING Ridgeview Estates Auburn,Washington GLS 07/28/2016 4572 AZS July 2016 4 North Ridgeview Estates Plat Hearing Examiner Packet Page 176 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 177 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 178 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 179 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 180 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 181 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 182 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 183 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 184 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 185 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 186 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 187 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 188 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 189 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 190 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 191 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 192 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 193 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 194 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 195 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 196 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 197 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 198 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 199 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 200 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 201 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 202 of 422 Drwn.CAM Checked AZS Date Mar.2017 Date 03/23/2017 Proj.No.4572.01 Plate 1 Earth Solutions NWLLC Geotechnical Engineering,Construction Monitoring EarthSolutionsNWLLC EarthSolutions NW LLC and Environmental Sciences Vicinity Map Ridgeview Estates Auburn,Washington NORTH NOTE:This plate may contain areas of color.ESNW cannot be responsible for any subsequent misinterpretation of the information resulting from black &white reproductions of this plate. Reference: King County,Washington Map 716 By The Thomas Guide Rand McNally 32nd Edition SITE North Ridgeview Estates Plat Hearing Examiner Packet Page 203 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 204 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 205 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 206 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 207 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 208 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 209 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 210 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 211 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 212 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 213 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 214 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 215 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 216 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 217 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 218 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 219 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 220 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 221 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 222 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 223 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 224 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 225 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 226 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 227 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 228 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 229 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 230 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 231 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 232 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 233 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 234 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 235 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 236 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 237 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 238 of 422 Drwn.CAM Checked AZS Date Mar.2017 Date 03/23/2017 Proj.No.4572.01 Plate 1 Earth Solutions NWLLC Geotechnical Engineering,Construction Monitoring EarthSolutionsNWLLC EarthSolutions NW LLC and Environmental Sciences Vicinity Map Ridgeview Estates Auburn,Washington NORTH NOTE:This plate may contain areas of color.ESNW cannot be responsible for any subsequent misinterpretation of the information resulting from black &white reproductions of this plate. Reference: King County,Washington Map 716 By The Thomas Guide Rand McNally 32nd Edition SITE North Ridgeview Estates Plat Hearing Examiner Packet Page 239 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 240 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 241 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 242 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 243 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 244 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 245 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 246 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 247 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 248 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 249 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 250 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 251 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 252 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 253 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 254 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 255 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 256 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 257 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 258 of 422 EXHIBIT 10 PRELIMINARY STORMWATER SITE PLAN, PREPARED BY BARGHAUSEN CONSULTING ENGINEERS, 11/16/2017 (LESS THE FOLLOWING SECTION WHICH ARE AVAILABLE UPON REQUEST: “BASIN RECONNAISSANCE REPORT”, “INVENTORY REPORT”, MODELING CALCULATION SHEETS, GEOTECHNICAL REPORT, AND CRITICAL AREAS REPORT); AND, WETLAND HYDROLOGIC SUPPORT, PREPARED BY SEWALL WETLAND CONSULTANTS, 11/15/2017 North Ridgeview Estates Plat Hearing Examiner Packet Page 259 of 422 -This page left intentionally blank- North Ridgeview Estates Plat Hearing Examiner Packet Page 260 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 261 of 422 Preliminary Stormwater Site Plan North Ridgeview Estates Auburn, Washington North Ridgeview Estates PlatHearing Examiner Packet Page 262 of 422 17426.004.doc TABLE OF CONTENTS 1.0 PROJECT OVERVIEW 2.0 ANALYSIS OF THE MINIMUM REQUIREMENTS 3.0 EXISTING CONDITIONS SUMMARY 4.0 OFF-SITE ANALYSIS REPORT 5.0 PERMANENT STORMWATER CONTROL PLAN A. EXISTING SITE HYDROLOGY B. DEVELOPED SITE HYDROLOGY C. PERFORMANCE STANDARDS AND GOALS D. FLOW CONTROL SYSTEM E. WATER QUALITY SYSTEM F. CONVEYANCE SYSTEM ANALYSIS AND DESIGN G. WWHM WETLAND HYDROLOGY CALCULATIONS 6.0 CONSTRUCTION STORMWATER POLLUTION PREVENTION PLAN 7.0 SPECIAL REPORTS AND STUDIES 7.1 GEOTECHNICAL REPORT PREPARED BY EARTH SOLUTIONS NW, LLC DATED JULY 28, 2016 7.2 CRITICAL AREA REPORT PREPARED BY SEWALL WETLAND CONSULTING DATED JUNE 20, 2016 7.3 SUPPLEMENTAL INFILTRATION EVALUATION AND RESPONSE TO CITY COMMENTS PREPARED BY EARTH SOLUTIONS NW, LLC DATED APRIL 6, 2017 7.4 REVISED CRITICAL AREA REPORT PREPARED BY SEWALL WETLAND CONSULTING, INC. DATED APRIL 28, 2017 7.5 WETLAND HYDROLOGIC SUPPORT MEMO PREPARED BY SEWALL WETLAND CONSULTING, INC., DATED NOVEMBER 15, 2017 8.0 OTHER PERMITS 9.0 OPERATION AND MAINTENANCE MANUAL 10.0 BOND QUANTITIES WORKSHEET North Ridgeview Estates Plat Hearing Examiner Packet Page 263 of 422 Tab 1.0 North Ridgeview Estates Plat Hearing Examiner Packet Page 264 of 422 17426.004.doc 1.0 PROJECT OVERVIEW This North Ridgeview Estates project is located on a 29.69-acre site within a portion of Section 33, Township 22 North, Range 5 East, Willamette Meridian, City of Auburn, King County, Washington. More particularly, the site is located southwest of the intersection of S.E. 284th Street and 214th Avenue S.E. Please see the enclosed Vicinity Map for an exact location of the project site. Currently, the site is undeveloped and is vegetated with pasture grass and a few scattered trees. The project site drains via sheet flow in a northerly direction with a total grade relief across the site of approximately 118 feet. Along the northerly property line is a wetland that is connected to a stream course. Portions of this wetland are located on the subject property, but the majority of the wetland is located on the properties to the north. Please refer to the wetland analysis report included in Section 7.0 of this report for reference. The site sheet flows to this wetland system all along the northern property line with some of the southern portion of the property sheet flowing in a slight northeasterly direction. For purposes of sizing the permanent flow control facility located in Tract E, which will be constructed with the final construction plans and utilized for the temporary erosion and sediment pond, the pre-developed condition was assumed to be forested land with Type C soils. The on-site soils are classified as Alderwood gravelly sandy loam (AgC, AgD, and AgB) per the enclosed soils map. A Geotechnical Report has also been prepared by Earth Solutions NW and is located in Section 7.0 and provides further discussion about the soils. With the proposed development, a large portion of the site (approximately 15.5 acres) will be retained in open space tracts. The new impervious surface is only anticipated to cover about 21- percent of the total site area. This proposed impervious area will consist of public roadways and walkways, gravel access roads and trails, private driveways and walkways, and roof areas for 30 future homes. Access to the project site will come from a public road connection to 124th Avenue S.E. along the west side of the site. The site will have sewer service. An off-site sewer extension is proposed to be installed within S.E. 285th Street (private road) and extended onto the site near the northeast corner of the project. A water line is proposed to be installed within the proposed on-site public road. Connections to the existing water main will be made within 124th Avenue S.E. and also the existing water main at the southeast corner of the site. Low Impact Development (LID) Best Management Practices (BMP's) will be implemented into the design of this development as required by the City of Auburn. The project is proposing to use "List #2" from the new City Stormwater Management Manual that was adopted on January 1, 2017. Please refer to section 5.0.C. of this report for a summary and analysis of the proposed BMP’s for this site. The detention facility located in this tract was sized per the 2012 Western Washington Hydrology Model (WWHM) requirements as adopted by the City or Auburn utilizing the historic condition of forest as the pre-developed condition. The water quality system located in this tract was sized to meet the Basic Treatment requirements. A Combined Detention/Wetpool is the proposed means of providing water quality for the site. Other permits anticipated for this project include an NPDES Permit from the Department of Ecology, also known as a Construction Stormwater General Permit, for construction on sites with over an acre of land disturbance. In addition, a W ater Line Extension Permit will be required from Water District 111, and a Sanitary Sewer Permit will also be required from Soos Creek Water and Sewer District. Building Permits, a Site Development Permit, and a Clear and Grade Permit will all be required from the City of Auburn. North Ridgeview Estates Plat Hearing Examiner Packet Page 265 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 266 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 267 of 422 Tab 2.0 North Ridgeview Estates Plat Hearing Examiner Packet Page 268 of 422 17426.004.doc 2.0 ANALYSIS OF THE MINIMUM REQUIREMENTS Minimum Requirement No. 1: Preparation of Stormwater Site Plan: Response: This report will meet the requirement for preparing a Stormwater Site Plan; therefore, this Minimum Requirement threshold is met. Minimum Requirement No. 2: Construction Stormwater Pollution Prevention: Response: This document will be prepared and included with the final Stormwater Site Plan. Minimum Requirement No. 3: Source Control Prevention: Response: Source control prevention will be addressed in the Operation and Maintenance Manual. Minimum Requirement No. 4: Preservation of Natural Drainage System and Outfalls: Response: This project site will discharge to the same downstream drainage course it does under existing conditions; therefore, this Minimum Requirement is met. Minimum Requirement No. 5: On-Site Stormwater Management: Response: The project is proposing to provide BMP’s per List #2 of the SWMM in order to meet this minimum requirement. Please refer to section 5.0.C. of this report for a detailed summary and analysis of the stormwater management system proposed for this project. Minimum Requirement No. 6: Runoff Treatment: Response: This project is providing runoff treatment meeting the Basic Treatment requirements for the developed site area. Treatment will be provided by the installation of several different types of BMP’s per List #2, as well as a Combined Detention/Wetpool facility located in Tract ‘E’. Minimum Requirement No. 7: Flow Control: Response: Flow control is being provided for this site in accordance with Figure 2.5.1A such that BMP's are being utilized in accordance with "List #2" where feasible for all hard surfaces. A combined detention/wetpool facility located in Tract E is also being implemented to provide flow control. The WWHM Model was utilized to size this flow control facility. Calculations are included within section 5.0.D. of this report. The project site was analyzed in a forested condition and Type C soils for the pre-developed condition. This is in accordance with the City of Auburn standards and, therefore, this project assumes it to be adequate for this site. Minimum Requirement No. 8: Wetland Protection: Response: There are three wetlands located along the northern boundary of the site. Wetland and buffer enhancement will be implemented with the proposed development. Minimum Requirement No. 9: Operations and Maintenance: Response: An Operation and Maintenance Manual will be prepared and included with the final Stormwater Site Plan. North Ridgeview Estates Plat Hearing Examiner Packet Page 269 of 422 17426.004.doc Minimum Requirement No. 10: Off Site Analysis and Mitigation: Response: Please refer to section 4.0 of this report for the Off Site Analysis. North Ridgeview Estates Plat Hearing Examiner Packet Page 270 of 422 Tab 3.0 North Ridgeview Estates Plat Hearing Examiner Packet Page 271 of 422 17426.004.doc 3.0 EXISTING CONDITIONS SUMMARY Under existing conditions the site is undeveloped and is vegetated with pasture grass and a few scattered trees. Trees are proposed to be retained wherever possible. The topography of the site slopes in a northerly direction with slopes ranging from approximately 5-percent to 30- percent. Total relief across the site is roughly 118 feet. Along the northerly property line is a wetland that is connected to a stream course. Portions of this wetland are located on the subject property, but the majority of the wetland is located on the properties to the north. Based on the type of soil on the project site, which is a 'C' type soil, and the moderately sloped topography, it is anticipated that there is the potential for erosion and sediment deposition from this project site. Appropriate measures should be taken to protect the downstream properties. With exception of the three wetlands and associated buffers that exist along the north boundary of the site, there are no other sensitive or critical areas per the Sensitive Areas Folios for this project site, which include no vegetative buffers, steep slopes, floodplains, geologic hazard areas, streams, etc. The site is bordered by large lot residential properties on the north and east sides of the development. As previously noted, portions of the properties along the north boundary line contain wetlands and a drainage course. Auburn Mountainview High School is located directly south of the project. An existing church, water tower, and 124th Avenue S.E. are located directly west of the site. This site does receive a small upstream basin area from the adjacent parcel containing the water tower (Tax Parcel No. 332205-9177). To the best of our knowledge, there are no existing fuel tanks anywhere on this project site. To our knowledge, there are no groundwater wells or septic systems on or within 100 feet of the site. The site is currently undeveloped. To the best of our knowledge, this project is not located in an aquifer recharge area or a wellhead protection area as defined by the Washington State Health Department, the Environmental Protection Agency, or by the City of Auburn, nor are there any Super Fund areas in the vicinity of the project that are tributary to or receive drainage from the project site. The site is located within Zone X, per the FEMA map located in Section 4.0 of this report. This means that the site is located in an area outside of the 500-year flood plain. Therefore, there is no impact from flooding on this project site under either existing conditions or with the proposed conditions on the site. As mentioned in Section 1.0, there are three small wetlands along the north boundary of the site. With the project development, the wetlands and buffers will be enhanced based on the approved mitigation plans. North Ridgeview Estates Plat Hearing Examiner Packet Page 272 of 422 Tab 4.0 North Ridgeview Estates Plat Hearing Examiner Packet Page 273 of 422 17426.004.doc 4.0 OFF-SITE ANALYSIS REPORT The field work for this off-site analysis was performed in November of 2016. The project site drains in a northerly direction, as described in the on-site analysis, via sheet flow. Along the northerly property line is a wetland that is connected to a stream course which was flowing during the field analysis. Portions of this wetland are located on the subject property, but the majority of the wetland is located on the properties to the north. Please refer to the wetland analysis report included in Section 7.0 of this report for reference. The site sheet flows to this wetland system all along the northern property line with some of the southern portion of the property sheet flowing in a slight northeasterly direction. The wetland system is surrounding a well-defined stream course. This stream course is shown on the enclosed downstream drainage map. Some historical maps refer to this stream course as "Westside Soos Creek." The majority of the stream flows come from drainage courses located to the west of 124th Avenue S.E. This stream drains through a well-defined vegetated channel in an easterly direction and is located approximately 50 feet north of the subject property's northwest property corner and approximately 300 feet north of the subject property's northeast property corner. From this northeast stream location, it continues approximately 1,400 feet through a well-defined channel, to the west margin of 132nd Avenue S.E. At this location the stream travels through a free flowing 42-inch diameter CMP culvert to the east margin of 132nd Avenue S.E. From this location, the stream continues to the east for approximately 200 feet then heads in a southerly direction through the Reber Ranch property in open channels and some cross culverts for an additional 1,300 feet. Then the channel drains to the east. There were no noticeable signs of erosion or flooding in the downstream system during the site investigation. North Ridgeview Estates Plat Hearing Examiner Packet Page 274 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 275 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 276 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 277 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 278 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 279 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 280 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 281 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 282 of 422 Tab 5.0 North Ridgeview Estates Plat Hearing Examiner Packet Page 283 of 422 17426.004.doc 5.0 PERMANENT STORMWATER CONTROL PLAN A. EXISTING SITE HYDROLOGY For the pre-developed condition on this project, the site was modeled as forested with on-site soils classified as a 'C' type soils, even though the site is currently covered with mostly pasture grass and a few scattered trees. All 20.97 acres of the site were modeled as forest with type 'C' soils. There is a small portion of the off-site Tax Parcel No. 332205-9177 that does drain onto the site as shown on the enclosed map. The on-site conveyance system and pond facility will be sized to account for this off-site basin area. Please refer to the enclosed Existing Basin Area Map for details regarding the on-site topography and existing basin areas. North Ridgeview Estates Plat Hearing Examiner Packet Page 284 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 285 of 422 17426.004.doc B. DEVELOPED SITE HYDROLOGY In the developed condition, there are two basins that were analyzed to determine the size of the proposed detention and water quality facility, one that flows directly to the Tract E drainage facility and one that bypasses that facility. The developed bypass areas will all be dispersed over existing undisturbed areas and have therefore been analyzed as "grass/lawn" in the developed condition. The total disturbed site area is approximately 20.97 acres. The basin area draining to Tract E totals 16.88 acres and consists of 8.38 acres of impervious surface and 8.48 acres of grass/lawn area. The developed bypass basin area totals 4.09 acres of grass/lawn area. Stormwater discharge from the Tract E drainage facility will be routed through a dispersal trench. The discharge from the developed bypass area will be dispersed through trenches and sheet flow across undisturbed areas on site, which matches the existing drainage conditions. Please refer to the enclosed Developed Basin Area Map for details regarding the developed basin areas and land cover. North Ridgeview Estates Plat Hearing Examiner Packet Page 286 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 287 of 422 17426.004.doc C. PERFORMANCE STANDARDS AND GOALS The project is proposing to meet the List #2 LID requirements based on the enclosed flow chart Figure 2.5.1A with regard to all proposed hard surfaces. For some of the hard surfaces, there are no feasible BMP's that will work for this particular site. For those surfaces, the developed stormwater runoff will be routed to the combined detention and wetpond that is located in Tract E. The detention facility was sized utilizing the WWHM program. This facility will match peak flows and duration to the pre-developed rates for the range of 50 percent of the 2-year storm to the 50-year storm. The wetpond that is proposed will meet the basic water quality requirements as required per the enclosed Treatment Facility Selection Flow Chart, Figure 2.1.1. Below is a list of the List #2 BMP’s (in order) along with a summary of how they were applied on this project. We have also included a copy of the requirements, application, design guidelines, and infeasibility requirements from the SWMM for each of these BMP’s with in this section for reference: Roofs: 1. BMP T5.10A (Downspout Full Infiltration) or BMP T5.30 (Full Dispersion) Based on soils information provided by Earth Solutions NW (ESNW), Full infiltration has been proposed for the roof areas on lots 1-11. Full infiltration is feasible with the roof areas on the remaining lots due to the soils in the area of those lots. Full Dispersion is not feasible for this project as the development does not retain at least 65-percent of the site in a forested or native condition. 2. BMP T7.30 (Bio-retention Cells, Swales, and Planter Boxes) Based on discussions with the Geotechnical Engineer, the native soils south of TP- 109 and TP-110 are “Till” soils which are very unreliable and generally do not produce the minimum hydraulic conductivity of 0.30 inches per hour needed for this drainage system. Also, groundwater seepage was encountered at a depth of 3 feet and 3.5 feet in TP-111 and Tp-112. With the proposed cuts and fills on lots 12-30, we believe that this BMP is not feasible. 3. BMP T5.10B (Downspout Dispersion Systems) Downspout dispersion systems have been proposed for lots 12-15, 28, and 30. This BMP is not feasible for the remaining lots as the lot areas do not provide the required flow path length and there is no adjacent open space tract down slope of the lot. 4. BMP T5.10C (Perforated Stub-out Connections) Perforated stub-outs have been proposed for lots 16-27, and 29. Runoff from the perforated stubouts will be collected and conveyed to the proposed detention and water quality facility located in Tract ‘E’. Other Hard Surfaces: 1. BMP T5.30 (Full Dispersion) North Ridgeview Estates Plat Hearing Examiner Packet Page 288 of 422 17426.004.doc Full Dispersion is not feasible for this project as the development does not retain at least 65-percent of the site in a forested or native condition. 2. BMP T5.15 (Permeable Pavements) Permeable pavement is not feasible for the proposed onsite roadways for a couple different reasons. The soils in the northern portion of the site (124th to about station 20+00) are acceptable for this BMP; however the road slopes exceed the maximum 5-percent slope allowed for porous pavement. The existing soils throughout the rest of the site are considered to be “till” type soils by ESNW. Based on discussions with ESNW, these soils will not provide a hydraulic conductivity rate of more than 0.3 inches per hour and are un-reliable for infiltration purposes. 3. BMP T7.30 (Bio-retention Cells, Swales, and Planter Boxes) Based on a review of the infeasibility requirements of this BMP, it is not recommended that they be installed on slopes exceeding 8-percent, or in areas where the hydraulic conductivity of the native soils are less than 0.3 inches per hour. The native soils in the northern portion of the site for Road ‘A’ (124th to about station 20+00) exceed the minimum infiltration requirements, but the road slope exceeds the maximum 8-percent for this BMP. The road slopes for the remaining road surfaces are less than the maximum 8-percent slope, but according to ESNW the native soils are “till” type soils which are un-reliable and will not produce the minimum 0.3 inches per hour hydraulic conductivity required for this BMP. 4. BMP T5.11 (Concentrated Flow Dispersion) or T5.12 (Sheet Flow Dispersion) Given the proposed plat layout, proposed grading, and existing topography, there are no areas available to provide dispersion of the runoff from the proposed road surfaces. Given this analysis and summary of the BMP’s noted above, all runoff from the hard surfaces will be collected via catch basins and conveyed to the proposed detention and water quality located in Tract ‘E’. North Ridgeview Estates Plat Hearing Examiner Packet Page 289 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 290 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 291 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 292 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 293 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 294 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 295 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 296 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 297 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 298 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 299 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 300 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 301 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 302 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 303 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 304 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 305 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 306 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 307 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 308 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 309 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 310 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 311 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 312 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 313 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 314 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 315 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 316 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 317 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 318 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 319 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 320 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 321 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 322 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 323 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 324 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 325 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 326 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 327 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 328 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 329 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 330 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 331 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 332 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 333 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 334 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 335 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 336 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 337 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 338 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 339 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 340 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 341 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 342 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 343 of 422 17426.004.doc D. FLOW CONTROL SYSTEM Please see the WWHM calculations on the following pages of this section for a detailed analysis of the detention pond sizing calculations. The detention pond is located in Tract E, which is in the northwest corner of the site. With the exception of the proposed bypass areas and roof areas that are being infiltrated or dispersed, all stormwater from the site will be collected and directed to the pond where it will be detained and released such that stormwater discharges will match developed discharge durations to pre-developed durations for the range of pre-developed discharge rates from 50 percent of the 2-year peak flow up to the full 50-year peak flow. The discharge will then be directed through a dispersal trenches located at the edge of the adjacent wetland buffer. These calculations account for the proposed BMP's that are proposed for the hard surfaces within the developed site area. North Ridgeview Estates Plat Hearing Examiner Packet Page 344 of 422 17426.004.doc E. WATER QUALITY SYSTEM The water quality system proposed for the drainage facility located in Tract E meets the Basic Water Quality Menu and is being provided by a Combined Detention/Wetpool facility. Since it is combined with the detention pond, it has been sized to meet the 24-hour runoff volume using WWHM, for the developed site condition. Please refer to the calculations on the following pages for the design of the water quality facility. North Ridgeview Estates Plat Hearing Examiner Packet Page 345 of 422 17426-Prel-Det-2017-09-11 9/19/2017 11:29:16 AM Page 16 Water Quality Water Quality BMP Flow and Volume for POC #1 On-line facility volume:1.2325 acre-feet On-line facility target flow:1.4811 cfs. Adjusted for 15 min:1.4811 cfs. Off-line facility target flow:0.8222 cfs. Adjusted for 15 min:0.8222 cfs. WETPOND CALCULATIONS Per criteria noted in Volume V, Chapter 10, of the 2012 DOE manual, the volume required for a Basic Wetpond shall be equal to or greater than the water quality design storm event (6 month, 24-hour storm). Per the WWHM calculations noted above, the WQ volume = 1.2325 acre-feet, which is equal to 53,687 Cubic-Feet. The proposed wetpond will provide is +/-56,400 Cubic-Feet. North Ridgeview Estates Plat Hearing Examiner Packet Page 346 of 422 Drywell Sizing Calculations Per 2012 DOE SWMM Section 3.1.1: On-Site Soils Described as: Medium Sands Roof Area (Assumed for Preliminary) = 2,800 sf Drywell Volume Required = 2,800 x (90cf / 1,000 sf) =252 cubic feet Drywell Diameter = 12 ft (4-ft min. diameter) Drywell Depth = 252 / (3.14 x (10)2 / 4) =2.2 ft When located in coarse sands and cobbles, drywells must contain a volume of gravel equal to or greater than 60 cubic feet per 1,000 square feet of impervious surface served. When located in medium sands, drywells must contain at least 90 cubic feet of gravel per 1,000 square feet of impervious surface served. North Ridgeview Estates Typical Lot North Ridgeview Estates Plat Hearing Examiner Packet Page 347 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 348 of 422 17426.004.doc F. CONVEYANCE SYSTEM ANALYSIS AND DESIGN This section will be completed with the final Storm water Site Plan. An initial time of concentration of 6.3 minutes will be utilized via the Modified Rational Method, a Manning's 'n' value of 0.14 will also be used. Pipes will be sized for the 100-year storm event. This provides a conservative design for sizing the conveyance facilities for this project site. A Basin Map will also be included with the conveyance calculations. North Ridgeview Estates Plat Hearing Examiner Packet Page 349 of 422 17426.004.doc G. WWHM WETLAND HYDROLOGY CALCULATIONS Enclosed within this section are the wetland fluctuation calculations for the wetland located downstream of the proposed Tract E drainage facility. For the purposes of this analysis, the existing land cover conditions were assumed to be pasture rather than the forested condition assumed with the detention calculations located in section 5.0.D. Please also refer to the Wetland Hydrologic Support Analysis that was prepared by Sewall Wetland Consulting, Inc. for additional information and analysis of the downstream wetland. This information is located in section 7.5 of this report. North Ridgeview Estates Plat Hearing Examiner Packet Page 350 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 351 of 422 Tab 6.0 North Ridgeview Estates Plat Hearing Examiner Packet Page 352 of 422 17426.004.doc 6.0 CONSTRUCTION STORMWATER POLLUTION PREVENTION PLAN This section will be completed with the final Stormwater Site Plan. North Ridgeview Estates Plat Hearing Examiner Packet Page 353 of 422 Tab 7.0 North Ridgeview Estates Plat Hearing Examiner Packet Page 354 of 422 17426.004.doc 7.0 SPECIAL REPORTS AND STUDIES Please see the enclosed Geotechnical Report prepared by Earth Solutions NW and a Critical Area Report prepared by Sewall Wetland Consulting, Inc. 7.1 Geotechnical Report Prepared by Earth Solutions NW, LLC dated July 28, 2016 7.2 Critical Area Report Prepared By Sewall Wetland Consulting dated June 20, 2016 7.3 Supplemental Infiltration Evaluation and Response to City Comments Prepared by Earth Solutions NW, LLC dated April 6, 2017 7.4 Revised Critical Area Report Prepared by Sewall Wetland Consulting, Inc. dated April 28, 2017 7.5 Wetland Hydrologic Support Memo prepared by Sewall Wetland Consulting, Inc., dated November 15, 2017 North Ridgeview Estates Plat Hearing Examiner Packet Page 355 of 422 Tab 8.0 North Ridgeview Estates Plat Hearing Examiner Packet Page 356 of 422 17426.004.doc 8.0 OTHER PERMITS Other permits anticipated for this project include: ·Site Development Permit ·Building Permit ·Water Main Extension Permit ·Sanitary Sewer Extension Permit ·Forest Practices Permit (FPA) ·Hydrology Project Approval (HPA) ·Right-of-Way Use Permit ·Construction Stormwater General Permit (NPDES) North Ridgeview Estates Plat Hearing Examiner Packet Page 357 of 422 Tab 9.0 North Ridgeview Estates Plat Hearing Examiner Packet Page 358 of 422 17426.004.doc 9.0 OPERATION AND MAINTENANCE MANUAL This section will be completed with the final Stormwater Site Plan. North Ridgeview Estates Plat Hearing Examiner Packet Page 359 of 422 Tab 10.0 North Ridgeview Estates Plat Hearing Examiner Packet Page 360 of 422 17426.004.doc 10.0 BOND QUANTITIES WORKSHEET This section will be completed with the final Stormwater Site Plan. North Ridgeview Estates Plat Hearing Examiner Packet Page 361 of 422 November 15, 2017 Steve Sturza City of Auburn 25 West Main Street Auburn, WA 98001 RE: Wetland hydrologic support analysis – Parcels#332205-9115, #9103 & #9154 City of Auburn, Washington SWC Job #16-145 Dear Steve, At your request, we have analyzed the wetlands on the North Ridgeview Plat which will ultimately receive stormwater from the plat. The purpose of this analysis is to determine what, if any impacts will occur to the wetlands from the release of the plats storm water. Specifically, we have focused on the increase in volumes of storm water for post development storm flows during the summer and growing season periods as you have requested. There are three wetlands on the site, Wetland A/C which contains a portion which is depression (Wetland A in northwest corner of the site) and a portion which is slope type (Wetland C). Wetland B is a very small slope type wetland. On the site, Wetland A/C consists of a narrow swale on the northwest with a slight slope to the north and extends off-site into a larger wetland area located off -site. The portion identified as Wetland C is a portion of this wetland that is slope like in character. The majority of Wetland A/C is located off -site to the north and east. The off-site portion contains a small stream known as Westside Soos Creek. The overall wetland complex slopes towards 132nd Avenue SE, and is approximately 10 acres in size. All water within this wetland drains to the east through the wetland, and draining from the wetland into Westide Soos Creek. The wetland outlets into a ditched stream channel east of 13 2nd Avenue and drains through the Reber Ranch in a maintained excavated ditch before eventually discharging to Soos Creek further to the south and east. There appear to be numerous area s of disturbance in the wetland to include excavated ponds, filled berms, livestock grazing and several storm water outflows from storm water facilities to the east. A review of this off-site wetland area reveals that the wetland contains a large amount of emergent wetland vegetated primarily with invasive reed canary grass. There are also some small sections of immature alder and cottonwood dominated forested portions of the wetland to the east with hardhack as a component along the edges of the reed canary grass. None of the wetland is a pristine and all within the depressional wetland area that would be impacted by any water regime change is already dominated by species that are well adapted to flashy and highly fluctuating water regimes. Sewall Wetland Consulting, Inc. PO Box 880 Phone: 253-859-0515 Fall City, WA 98024 North Ridgeview Estates Plat Hearing Examiner Packet Page 362 of 422 North Ridgeview/#16-145 Sewall Wetland Consulting, Inc. November 15, 2017 Page 2 No areas within the wetland have been observed to contain sensitive plant species or unusual plant communities that would be sensitive to minor changes in hydrologic characteristics. No state or federally listed threatened or endangered wildlife is known or has been observed in this wetland. The City has stated it has observed a great blue heron off-site to the north of the site within Wetland A. We have not observed any herons on or near the site, nor have we observed any nests or rookeries. The great blue heron has no Federal protection status except as a migratory bird. The great blue heron is listed by WDFW as a State Monitor species. Washington Department of Fish and Wildlife maintains a State Monitor Species list that includes animal species for which they monitor status and distribution. Little is known about many of these species, but biologists are concerned about their well-being. No specific protections are placed upon these species. However, the nests and rookeries of great blue herons are protected. As previously stated, no nests or heron rookeries were observed on or near the site. It is common to see great blue herons hunting in large areas which includes wetlands and agricultural lands. However they usually nest in mature forested areas which are not present on the site. Any herons observed near the site would have most likely been foraging for food in part of their territory, which can be several miles from nesting areas. As stated above, the existing plant community composition is already shaped by past disturbance and a flashy hydrologic regime. As depicted on page 10 of the WWHM calculations prepared by Barghausen Engineers and reproduced on page 2 of this letter, the pre-development flows are fairly similar to post development flows, with a slightly lower flow rate to the wetland in certain events in the post development condition. Above: Taken from page 10- of the Barghausen Engineers WWHM calculations for the project. However, slightly more water will enter the wetland in the post developed period than pre- developed. The result is slightly more water will enter the wetland spread over a longer period of North Ridgeview Estates Plat Hearing Examiner Packet Page 363 of 422 North Ridgeview/#16-145 Sewall Wetland Consulting, Inc. November 15, 2017 Page 3 time. This is particularly obvious in the period from May-September where the volume of storm water released is anywhere from 0.5-1.5 acre feet over the pre development volumes. This May-September period is when the wetland in general would be dry with no surface water. The addition of this amount of water in the May-September period should have little impact on this wetland, as the soils are generally just saturated fairly deep, or dry in this time period. The additional water would not be large enough in volume to create more than a temporary increase in soil saturation levels. The amount of water is small enough over the 10 acre wetland to not create any significant ponding or inundation that could impact a wetland plant community. The only potential change is a slight increase the growing period of vegetation in the wetland due to soil moisture potentially being available longer in the dry season. Above: Stormwater release volume data from Barghausen Engineers site specific report. The proposed storm water pond for the site will disperse this water to Wetland A/C through a dispersion trench along its eastern buffer edge allowing site water to reach the wetland. Wetland A is an emergent wetland vegetated primarily with reed canary grass, this includes much of the wetland off-site to the north. This is a non-native invasive species that is tolerant, of a highly fluctuating hydrologic regime. It is unlikely that the addition of additional water from the pond will alter or impact this wetlands plant composition or function in any way. The hydrology of the Wetland A already appears “flashy” in the depressional portion from roadside runoff entering the wetland undetailed. The plant species (reed canary grass on-site and hardhack and some willows off-site) present within this wetland are already adapted to this flashy hydrology. The release of stormwater from the proposed project should have no impacts on the wetland nor should it result in changes in the plant community or its wildlife functions. North Ridgeview Estates Plat Hearing Examiner Packet Page 364 of 422 North Ridgeview/#16-145 Sewall Wetland Consulting, Inc. November 15, 2017 Page 4 If you have any questions in regards to this report or need additional information, please feel free to contact me at (253) 859-0515 or at esewall@sewallwc.com . Sincerely, Sewall Wetland Consulting, Inc. Ed Sewall Senior Wetlands Ecologist PWS #212 North Ridgeview Estates Plat Hearing Examiner Packet Page 365 of 422 -This page left intentionally blank- North Ridgeview Estates Plat Hearing Examiner Packet Page 366 of 422 EXHIBIT 11 CRITICAL AREAS REPORT, PREPARED BY SEWALL WETLAND CONSULTANTS, 4/26/2017 North Ridgeview Estates Plat Hearing Examiner Packet Page 367 of 422 -This page left intentionally blank- North Ridgeview Estates Plat Hearing Examiner Packet Page 368 of 422 April 28, 2017 Jeff Potter Integrity Land LLC 27203 216th Ave SE, Suite 5 Maple Valley, WA. 98038 RE: Revised Critical Area Report – Parcels#332205-9115, #9103 & #9154 King County, Washington SWC Job #16-145 Dear Jeff, This report describes our observations of jurisdictional wetlands, streams and buffers on or within 200’ of Parcels#332205-9115, #9103 & #9154 located on the east side of 124th Avenue SE in the City of Auburn, Washington (the “site”). The site consists of a 29.7 acre irregular shaped accumulation of 3 parcels, located within the SE ¼ of Section 33, Township 22 North, Range 5 East of the W.M. METHODOLOGY Ed Sewall of Sewall Wetland Consulting, Inc. inspected the site on April 20, 2015 and May 20, 2016. The site was reviewed using methodology described in the Corps of Engineers Wetlands Delineation Manual (Environmental Laboratory, 1987), and the Western Mountains, Valleys and Coast region Supplement (Version 2.0) dated June 24, 2010, as required by the US Army Corps of Engineers and City of Auburn. Soil colors were identified using the 1990 Edited and Revised Edition of the Munsell Soil Color Charts (Kollmorgen Instruments Corp. 1990). Sewall Wetland Consulting, Inc. PO Box 880 Phone: 253-859-0515 Fall City, WA 98024 North Ridgeview Estates Plat Hearing Examiner Packet Page 369 of 422 Integrity Plemmons/#16-145 Sewall Wetland Consulting, Inc. April 28, 2017 Page 2 Above: Vicinity Map of the site. OBSERVATIONS Existing Site Documentation. Prior to visiting the site, a review of several natural resource inventory maps was conducted. Resources reviewed included the National Wetland Inventory Map and the NRCS Soil Survey online mapping and Data and the King County iMap website with wetland and stream layers activated. North Ridgeview Estates Plat Hearing Examiner Packet Page 370 of 422 Integrity Plemmons/#16-145 Sewall Wetland Consulting, Inc. April 28, 2017 Page 3 Soil Survey According to data on file with the NRCS Soil Survey, the majority of the site is mapped as moderately well drained Alderwood soils of various slopes. There are two areas of the site along the north edge mapped as poorly drained Norma soils. Norma soils are considered “hydric” or wetland soils. Above: USDA Soil Survey Map of the sit North Ridgeview Estates Plat Hearing Examiner Packet Page 371 of 422 Integrity Plemmons/#16-145 Sewall Wetland Consulting, Inc. April 28, 2017 Page 4 National Wetlands Inventory (NWI) According to the NWI map for the site, there is a large forested and emergent wetland north of the site that extends onto the site on the northeast, and northwest corners. Above: National Wetlands Inventory Map of the site. WADNR Fpars Stream Mapping According the WDNR Fpars stream mapping of the site, there is a Type N stream located north of the site several hundred feet. North Ridgeview Estates Plat Hearing Examiner Packet Page 372 of 422 Integrity Plemmons/#16-145 Sewall Wetland Consulting, Inc. April 28, 2017 Page 5 Above: WDNR Fpars stream mapping. Washington Department of Fish and Wildlife Priority Habitats Data Search According to the WDFW Priority Habitat Website with Public access layers activated, a wetland (purple shading) is located on portions of the north edge of the site. North Ridgeview Estates Plat Hearing Examiner Packet Page 373 of 422 Integrity Plemmons/#16-145 Sewall Wetland Consulting, Inc. April 28, 2017 Page 6 Field observations Uplands The site is located at the top of a hill that slopes to the north and slightly to the south on the south end of the site. The site is a pasture area that appears to be cut once a year. The site contains a large barn in the center of the site as well as the remains of several other agricultural structures. The site contains a few scattered trees including douglas fir, red alder and big leaf maple. The majority of the site is vegetated with a mix of sweet vernal grass, orchard grass, bedstraw and bluegrass. Portions of the southwest corner of the site appear to have been scraped and possibly graded in the past. Much of the soil profile is disturbed in this area. There are also large thickets of Himalayan blackberry scattered throughout the site. Soil pits excavated within the upland areas revealed gravelly sandy loam as well as a gravelly fill material soils in disturbed areas with colors of 10YR 3/3-3/4. Wetlands As depicted on the various inventories, a large wetland located to the north of the site. This wetland appears to overlap onto the site on the northwest and northeast corners. There is also a small isolated wetland near the center of the norther side of the site. Below is a description of these areas; Wetland A/C Wetland A/C consists of the apparent southern edge of a larger wetland that extends off-site to the north as depicted on several inventory maps. The edge of this wetland was flagged with flags A1-A15 and C1-C14. North Ridgeview Estates Plat Hearing Examiner Packet Page 374 of 422 Integrity Plemmons/#16-145 Sewall Wetland Consulting, Inc. April 28, 2017 Page 7 The portion of these wetlands on-site consists of a narrow finger along the northwest corner of the site, and a sloping lobe along the northeast corner of the site. The wetland on-site is dominated by reed canary grass and bluegrass. The eastern lobe delineated by the “C” flag line contains scattered skunk cabbage amongst the reed canary grass. The wetland off-site appears to be a disturbed mix of pasture and forested wetland with a heavy blackberry understory. The wetland is located at the upper end of a tributary of the West Fork of Soos Creek. The wetland extends north from the site and does not extend any additional buffer onto the site as shown on the wetland map (attached). Soil pits excavated within the wetland revealed a mix of mottled gravelly sandy loam on the west which has the appearance of being scraped or graded, and a black, silt loam with redoximorphic concentrations on the east. The western lobe had some soil saturation on our earlier April visist to the site but was dry in May. The eastern lobe still contained areas of saturated soil. The eastern lobe of the wetland is a slope l type wetland but the portion to the north off-site is a depressional wetland and as such, the wetland was rated as a depressional wetland. Using the US Fish and Wildlife Wetland Classification Method (Cowardin et al. 1979), Wetland A would be classified as PFO1C (palustrine, forested, deciduous, seasonally flooded) and PEM1C (palustrine, emergent, persistent, seasonally flooded). Using the WADOE Wetland Rating system and rating the wetland as a depressional type wetland, this wetland scored a total of 40 points with 16 for habitat. This indicates a Category II wetland. A Category III wetland with <20 habitat points in the City of Auburn (AMC 16.10.090.E.1) have a 25’ buffer measured from the wetland edge. Wetland B Wetland B was flagged with pink “Wetland Delineation” flagging labeled B-1 through B-15. Wetland B is located near the north property boundary and is a small, isolated slope-type wetland. North Ridgeview Estates Plat Hearing Examiner Packet Page 375 of 422 Integrity Plemmons/#16-145 Sewall Wetland Consulting, Inc. April 28, 2017 Page 8 Wetland B is a slope wetland with emergent vegetation. Dominant vegetation within Wetland B includes reed canary grass, buttercup and soft rush. Soil pits excavated within the wetland revealed a 16-inch layer of silt loam with color or 10YR 2/1 and common, medium distinct redoximorphic concentrations. Soils within the wetland were saturated within 12-inches of the soil surface during our site visit in April of 2015 and were moist during the May 2016 site visit. According to the United States Fish and Wildlife Service (USFWS) wetland classification method (Cowardin et al. 1979), Wetland B would contains areas that would be classified as PEM1E (palustrine, emergent, persistent, saturated). Using the WADOE Wetland Rating system and rating the wetland as a slope type wetland, this wetland scored a total of 24 points with 6 for habitat. This indicates a Category IV wetland. A Category IV wetland with 23 habitat points in the City of Auburn (AMC 16.10.090.E.1) have a 25’ buffer measured from the wetland edge). Buffer Enhancement As required per ACC 16.10.090.A, a buffer enhancement plan has been prepared for the wetlands and buffers on the site due to existing degraded conditions. The proposed enhancement plan depicts clusters of native trees and shrubs within these areas to increase species richness, structure and habitat. In addition, the proposed plantings should help shade out invasive reed canary grass within the wetlands. If you have any questions in regards to this report or need additional information, please feel free to contact me at (253) 859-0515 or at esewall@sewallwc.com . Sincerely, Sewall Wetland Consulting, Inc. Ed Sewall Senior Wetlands Ecologist PWS #212 North Ridgeview Estates Plat Hearing Examiner Packet Page 376 of 422 Integrity Plemmons/#16-145 Sewall Wetland Consulting, Inc. April 28, 2017 Page 9 Attached: Wetland Map Data sheets Rating Forms North Ridgeview Estates Plat Hearing Examiner Packet Page 377 of 422 Integrity Plemmons/#16-145 Sewall Wetland Consulting, Inc. April 28, 2017 Page 10 REFERENCES Cowardin, L., V. Carter, F. Golet, and E. LaRoe. 1979. Classification of Wetlands and Deepwater Habitats of the United States. U.S. Fish and Wildlife Service, FWS/OBS-79-31, Washington, D. C. Environmental Laboratory. 1987. Corps of Engineers Wetlands Delineation Manual, Technical Report Y-87-1. U. S. Army Corps of Engineers Waterways Experiment Station, Vicksburg, Mississippi. Muller-Dombois, D. and H. Ellenberg. 1974. Aims and Methods of Vegetation Ecology. John Wiley & Sons, Inc. New York, New York. Munsell Color. 1988. Munsell Soil Color Charts. Kollmorgen Instruments Corp., Baltimore, Maryland. National Technical Committee for Hydric Soils. 1991. Hydric Soils of the United States. USDA Misc. Publ. No. 1491. Reed, P., Jr. 1988. National List of Plant Species that Occur in Wetlands: Northwest (Region 9). 1988. U. S. Fish and Wildlife Service, Inland Freshwater Ecology Section, St. Petersburg, Florida. Reed, P.B. Jr. 1993. 1993 Supplement to the list of plant species that occur in wetlands: Northwest (Region 9). USFWS supplement to Biol. Rpt. 88(26.9) May 1988. USDA NRCS & National Technical Committee for Hydric Soils, September 1995. Field Indicators of Hydric Soils in the United States - Version 2.1 North Ridgeview Estates Plat Hearing Examiner Packet Page 378 of 422 WETLAND DETERMINATION DATA FORM - Western Mountains, Valleys, and Coast Region PfolccUSIIn: —I .x^ Cys^-J - P I C AVS *^CrlvfCcuntv: /4l/W <*•— Sampling P«K ___]^___S' Appiicarti/Owna: , Stow Sampling Point-.. Invwlloatorfat S-t \, Township. Ratine: , landform rhlltslope, tetTPco, eta): Sobreglon (IRR)' _____________ . ™_ . Local relief (concave, convex, none):, Long: . NVV1 classification: _ slope (%):„ . Datum; Soil Map Unit Name: . : Are cllmeth/hydrplogic conditions on the sltetyptcal for this time of year? Yes r**No (If no, explain in Remark*,) AreVegetilion .Solt _, or Hydrology significantlydisturbed? Are "Norma! C_rr_ne~sf present? Yea No , Are VegetilSon . Soil , or Hydrology naturally problematic? (if needed, explain any answers In Remarks.) SUMMARY OF RND1NSS - Attach site map showing sampling point locations, transects, Important features, etc. Hydrophyte Vegetation Present? Yas,. J_^TJO „_,,_ Hydftc SWi Present? Yes l^Jts^ is the Sampled Are* / within a Wetland? Ye*' No WettandHydrolow Present? Y»__j__T No , Remarks: VEGETATION - Use scientific names of plants. Tree.fflraliim. (Plotto:. 1. ________ % Cow. •__- . .SIM;,, Saplin_irub Stratum ^Plolsfee:. 1. Hem Stratum, (Plotsf_r__ 2 _ 3. _________ 4. a-, IPO.. s ToUd Cover WoodyVjne Stratum (Plot ska:. 1. % Bar* Ground In Herb Stratum _ TttatAreOBL FAOW.orFAC: Total Number of Dominant Spades Across All Strata: Percent of Dominant Spades That Are OBL, FAOW, or FAC: _ (A) _ (9) Prevalence index womttheet: Total 36 Cover of: OBL spedes , FACW Specie* . FAC species FACU specie* . UPL species . Column Totals: .(A) . Prevalence index * B/A * .(B) Hydmphytia Vegpttttfon trWicatom; __^Dominsfr«> Te*t >50iJ5 Prevalence Ind*}fls_k0.r Morphological Adaptations' (ProvWe supporting data in Remarks or on a separate sheet) . ., WeUand NonA/eacular Plants' Problematic Hydrophytfc Vegetation1 (Explain) ^Indicators pf hydrlc wland watiand hydrology must be present, wiiess disturbed orprobtematfc. Hydrophytic Vegetation Present? Yea_ US Army Corp* of Engineers Western Mountain*, VaHeys, em) Coaat-lnlerim Ve_lon SOIL Sampling Point. _______ Profile Description: (Describe to the dopth needed to document the Indicator or oonflfm the absence of Indicator*.) Depth . . Matrix _________________ _____ Color (moist) %, , Color (moist) % 'fVce\' , Texture Remarks 'Type: OConcentration. D*DePtetiOfr. RM=Reduced Matrix, CSaCoveredor Coated Sand Grains. 'Location: PL^Pore t_iq. hi=iv_x. ' Imticatons for problematic Hydrlc Solta': _ 2cmtouck(A10) net Parent Material (TF2) _ Other (Explain in Remsrita) HyiMo Soil Indicators: (Applicable to all Hislo*ol(A1) Hi»llo6plp_n(A_) „ Black Histic (A3) _ Hydrogen sutfide (A4) Depleted Below Dark Surtsce (A1 1) Thick Dark Surface (AW) Sandy Mucky Mineral (S1) „ Sandy Played Matrix (S4) LRRs, unless otherwlaa noted.) _ Sandy Redox (85) Stripped Matd«(S6) _ Loamy Mucky Mineral (F1) (except MLRA1) Loamy GieyedMaWxiPJ] _ Depitted Matrix (F3) __r1_ox Dark Surface (F6) . Depleted Dark Surface (F7) Redox Depressions (FS) indicators of bydrophytic vegetation and wetland hydrology must be present, unless disturbed or problematic. Restrfatfve Layer [tf pfestwt)!; _ y i yptf» —. ____ __ Depth flnrhflt): Hydrta Soil Present? Yea No„ HYDROLOGY Wetland Hydrology ItidtntbH*: Prlmprv Indtpetors f mtntmurr), pf one reguifed: check alt tliat at?RW> Surfece Waler(At) __. High Water Tsbte{A2) ,,.„ Saturation (A3) ___ „ Water Marks (B1) __, „ Sedirnenl Deposits (82) „ Drift Deposits (BS) „ Algei Mat or Crust (B4) . , Iron Deposits (B6) Syrface 5«l Crerfca (BO) „ fnurwia«on V/sWe on Mrial Imagary (8?) ___ Sparsely Vegetated Concave Surfece (68) Water-SUtneo' Leaves (,B9) (except MLRA 1,2,4A, *nd 4B) «ait Crusl (B11) Acjuatlc Invertebrates (B13) Hydrogen Sutfide Odor (CI) Oxldfcted Rhtzospheres along Living Roots (C3) presertca ot Reduced Iron {OA) Recent Iron Reduction !rt Tilled Soils (C5) Stunted or Strewed Plants <D1) (LRR A) Other (explain in RemarKs) §¥_?_d._y trvpjfqatofs ^ w rrjpT.e (-ett_fi-ed'| _ Water-Sfalned Leave* (B81 (MLRA1, i, 4A, and 4B) Dvalnaoo Pptiems{Bio) __ Dry^awn Water Table (C2) Qaturation Visible on Aerial Imagery (C8) ^_ Qeomorpnlc Position (D2) ,., ShallowAquitard(D3) . FAC>N6utralTast(D5) Raised Ant Mounds (D6)(LRR A) , ,, Frost-Heewa Hummocks (07) Field Observations: Surface Water Present? Yes __ No iXpeoth Cnches) Water Table Present? Yes, No S Death (inctiea) Saturation Present? Yes No_f_ Depth (kicties; (includes caoiUarv frinfle) Wetland Hydrology Present? Ye»___^No Describe Recorded Data (stream gauge, mordtoring well, aerial photos, previous inspectiona). If available: 3*1 US Army Corps of Engineers Western Mountains, Valleye. and Coast- Interim Votslon North Ridgeview Estates PlatHearing Examiner Packet Page 379 of 422 Project/Site; AppUcantfOwner: „ Investigators): __ _____ WETLAND DETERMINATION DATA FORM - Western Mountain-, Valleys, and Coast Region X^ly.^) * r?U''^*^JCnvf_nlv: /QvW»-_ SamptaotM.; S-1t>"/(f State: _____ Sampling Point: _______ Ur_fbrm [hlltsiope, terrace, etc.):._ gubregion (LRR)' ., 301) Map UnH Name: , Saclton, Township. Ratine: ,,, , „ Localralref(concave.convex,none).. , , Lorry, , , Slope „ . NWi.c)n*4atcaiion:_ Are cJim_o I hydrologlc conditions on the arte typical for this time of year? Yes Are Vegetation Soil , or Hydrology __ _ significantly disturbed? Are Vegetation, ,,,,,. SoH . or Hydrology _______ naturally problematic? _No _ (ifno, explain fn RemarkB.} Are 'Norma! Cfrftumatancas' present? Y____ (if needed, explain any answers In Remarks.) Hydrophyte VefJ*totion Present? Yas ; No r Hy«lo Suit Present? Yes No , f , Wetland HydrologyPresent? Yes No___T fa the Sampled Area / within a Wettand? Yes No Remarks VEGETATION - Use setentlfio names of plants. 1. W.SWum, (piot sue: _ 1. 2. 3. _ 4 Absolute Dominant Indicator It Cover Species? ___ Saolina^hrub Stratum (PloUfee:. 1. 2. ____________ 3. 2- _______ 3. 4. 3 6. ______ 7. Herb Stratum (Ptotsize:_ t. ________ .___ * Total Cover _s_ Woodv Vfne Stratum (Plotinza;. % Bore Ground in Herb stratum „ _*Total Cover Dominance Test worksheet Number of PcminantSpeciee_ That Are OBL. FAcW.orFAC: Total Number of Dominant Species Across All Strata: Percent of Dominant SpeoJes That Are OBL, FAGW. or FAC: *__ "(AT" (B) (A/8) Prev*i0rwe index worKsheet: Total % Cover oft . _ .Multiply, bv: . OBLspedes r FACW species , FAC species . FACU specie* . UPL species . Column Totals: , .(A) . Prevalence Index a B/A * „ Hydrophytto Vegetation rndlcatore: OomlnrtnceTe4tte>50% Prevalence Index is S3.Q1 Morphological Adaptations1 (ProvWe supporting data in Remarks or on a separate street) Watiand Non-VesculHr Plants' ProbtamallaHyd_phytfc^ "•indicators pf hydricsolatid wetland hydrology must be present unless disturbed or problematic. Hydrophytic Vegetation present? U$ Army Corps of Engineers Western Mountain?. Valleys, and Coast«interim Version SOIL Sampling Point: r v 1 Profile Description: (Describe to the depth needed to document the indicator or corfflrm the absence of Indicators.) ' ™ Oepth M'Hn Redox.Ffa.tur.M .„,, __ (Inches) , ,PWMM.,,._,,,-.»i Cdgr(moist),.,,,. ft ___ loo Texture , Reroarka //, "-^/JIZL „____- GJ<- .. *Type: .C^o^ntr^onyCNqe^apr), RM^educed Matrix. C^gCt^e^or.-Cd^ted^rtd grains. Hydrlc Solt Indicators: {AppHcablo to ait LRRsf unless otherwisa noted.) HWosol(At) HJ$ti&_pipeddn(A2) _ Black HMte (A3) Hydrogen Sutttde (A4) Depleted Below Dark Surface (A11) _ Thick Dark Surface (A12) .... .Sendy Mucky Mineral (S1) Sandy Oleyed Matrix (S4) ,., , Sandy Redox (OS) Stripped Matrix (B6) Loamy Mucky Mineral (F1) (except MLRA1) Loamy Gieyed Matrix (F2) , Depleted Matrix (F3) __ Redox Dark Surface (FQ) , . Depleted Dark Surface (F7) Redox Depressions (F8) •ocatjon: Pt*Pore Urtlnp. MHVtebiK, Indicators• tFor problematic Hydrlc SoHs': „ acmMuck(AlO) Red Parent Mwenaf (TF2) OthertExplofntn Remarks) indicators, oi hydrophytic vegetation and wetland hydrology nvust be present, unless disturbed gr problematic. Restrictive Layer (If present): Type. .„.,, , Depth f inches L-Hydrlc Sell Present? Yea No, Remarks: HYDROLOOY Wetland Hydrology Indicators: Primary Indicators fmlnlmum pf one requited: check ml that apply) Surface Water (At) High Water Table (A2) Saturation (A3) Water Marks (Bf) Sediment Deposits (B.) _ Oral Deposits (BS) Algal Mat or Crvst (fM) _ Iron Deposits (B6) Surface Soil Crocks (Bo) Inundation Visible on Aertsl Imagery (B7) Sparsely Vegetated Concave Sutfaca (B?) Water-Stained reaves (B9) (except MLRA •t,2,4A,and4B) Sail Crust (B11) _ Aquatic trWedebrates (B13) _ Hydrogen Sulfide Odor (CI) _ Ow'rjired Rhlzospberes along Uving Roots (C3) Presence of Reduced Iron (04) Recent Iron Reduction in TiBed Soils (C6) Sluntcd or Stressed Plants (D1) (LRR A) gih/-(Explain In Remarks) Secondary IndJcatprs a or more requ»ed> Water-Stained Leaves (89) (MLRA 1,2, 4A, and 48) , Drainage Patterns (610) Dty-Season Water Table (C2) Saturalioh Vlsibte on Aerial Imagery (C9) Qeomorphic Position (02) _ ShaHow Aquitard (D3) _ FAC.NeutralT_st(D5) „ Raised Ant Mounds (D8)(LRR A) _ Frost-Heave Hummocks (D7) Field Observatlonst Surface Water Present? WaierTaWe Present? Saturation Present? (includes capWary fringe) Yee Yes Yes . Ms , /Oeb No / Qeff Depth Crnchea):_ . No _____ Defim (hciies): _ . No____Depth (Inches):. Wetland Hydrelogy Present? Yo»_ Describe Recorded Data (stream gauge, monitoring weU, serial photos, previous inapecBona). if available: U5 Army Corps of Engineers Westorn Mountains, VallBys, and Coast-Interim Version North Ridgeview Estates PlatHearing Examiner Packet Page 380 of 422 WETLAND DETERMINATION DATA FORM- Western Mountains, Vatlejs, and Coast Region Prok-ct/SltB: t-y»'^>] - P I <f ^JClly>Counlv: /^^W fW1 SamoBm Dale: _>J_?.(___X' Appiicanyownar: , Imwtigalorfs): ? & _-*- *_>«_ \, Range:. __ Sampling Dale: _ . State: J___ SampifrtgPoint:. ____ Landform thillslope. terrace, etc.)'-,, Subreglon (LRR)- _______________ Soil Map Unit Name; _ Local roliaf (concave, convex, none): _ ... . . ,. Long: „ NW1 ctessiffcatlon: _ „ Slope \%y.~. _ Datum: Are cflmafe / hydmtogic conditions on the site typical for this fime of year? Yes.... t„rTwo (If on, explain In Remar ks.) Are Vegetation Soil _, __., or Hydrology significantly disturbed? Are "Normal Circumstances* present? Ye*, . _/** No Are VegebUon __, Solf , or Hydrology ^ naturally probiamatic? (If needed, explain any answers In Remarks.) SUMMARY OF FINDINGS - Attach site map showing sampling point locations, transects* Important features, ©tc. Hydrophyte Vegetation Present? Hydrlc ftfl Present? Wetland Hydrology Present? Yes, ^_ No Yes,.. „ .,. Jlo .. Yes y Ho 19 the Sampled Area, within a Wetland? Yes 1 Remarks: VEGETATION - Use scientific names of plants. Absolute Dominant Indicator _>caver. jte^...Swy».. Dominance Test worksheet Number-of DomlnajitSpedee ~7 — That Are OBi, FACW.orFAC: c— Tree Stratum . (Plotsiw:. 1. 2. 3 4. SarjIlnaiShrub Stfatum .Plot size:. 1 1. 3. 5._ Herb Stratum (Plotsi»>:_ L____3____ 2. 3, •»•__ 6, 7, -•Total Cover Woodv Vine Stratum (Plcrtsiza:. % Bare Ground In Herb Stratum „ Total Number of Dominant Specfes Across Alt Strata: , PercerHofr^rrinantSpacfes . _^>_>> That Are OBL, FACW. or FAC: /. (B) (A/B) Prevaierwe index worksheet: Total % Cover 6ft ,, .Multiply by: OBL spades . FACW specie* „ FAC species „ FACU species . U PL species . Column Totals: , Prevalence Index •* EVA » . x1* . X2* . x3=> . X4« , xs* .(A) .(B) r^rophy-tf VefletoifOfl mtfcetetu' __jMl)omlnsnce Test is >S0% Prevalence Index l$_LQ' . , Morphologrcel Adaplatiws' (Provide supporting data in Remarks or on a separate sheet) , , WeUand New-Vascular Plants' Problematic Hydrophytic Vegelatten1 (Explain) 'ftidteatort ofhydric wfUnd wetland hydrofogy must-bo present, -unless disturbed or problematic. Hydrophytio Vegetation Present? US Army Corp* of Engineers Western Mountain?, Valleys, and Coast- Interim Version i SOIL Sampling Point: ^_J Profile Description*. (Describe to the depth needed to document the indicator or cortftmi the absence of Indicator*.) Depth Malrix Redox Features finr-has).., Cojorjrripist) Color (moist) % Type' „ ...TffjtMK,. __ 221 _______ __. Remarks *Tvpa; C><_ain_on. D=-Depk.lion, RM-fteduoed Matrix. CSsCovered or Coated Sand Grains. Hydric Soil indicators: (Applicable to all LRR-, unless otherwise no-ted.) _ Histosol (A1) Hlslto_pip_n(A-) _ Slack Histic (A3) _ Hydrogen Sulfide (A4) Depleted Below Dark surface (AM) Thick Dark Surface (At 2) _ Sandy Mucky Mineral (S1) Sandy etoyed Matrix ($4) _ Sandy Redox (SS) Stripped Matrix (89) _ Loamy Mucky Mineral (F1> (except MLRA 1' LoanvGleyed Matrix (F2) _ QaefSied Matrix (F3) _f-_Jox Dark Surface (PS) . Depleted Dork Sltrfac- (F7) , , Redox Depressions (F8) "Location: PL*Pore Lining, M*Mabfc tn—eators for problematic Hydrlc Soils*: 2cmMuok(A10) _ Red Parent Materiai (TPS) _ Other (Explain hi Remarks) *!nr_Iora of hydrophytio.vegetation and wetland hydrology must be presenL unless disturbed or problematic. Restrictive Layer (if present): jyne: Depth (inches):,, , , HydHo Soil Present? Yea , r n0_^ HYDROLOGY WeUandHydrologyIndfcatom: '''' " Prlm&rv Incftpator-s fm|nlmum pf one required; check ail lha,t apply) Surface Water (A1) High Water T9ble(A2) Saturation (A3) Water Marks (B1) ,,.._ Sediment Deposits (t32) Drft Depusits (B3) __, Algal Mat or Crust (B4) . , Iron Deposits (Bfi) , Surface Soil Cracks (BQ) inundation Visible on Aariat Imagery (B7) .,_„ Sparsely Vegetated Concave Surface (B8) . Water-Stained Leaves (Bfl) (excapt MLRA 1,4,4Afand48) .Salt Crust (B11) . Anuatic invertebrates (B13) . Hydrogen Sulfide Odor (CI) _ Ow*dfzed RhEcosphere? along Llvfne Roots (C3) . Presence ot Reduced Iron (04) , Recent Iron Reduction tn Titled Soils (_•$) . Sluntcd ex Stressed Plants (D1) (LRR A) . Other (Explain in Remiwks) Secondary IndJcalDrs 17 or more r&dtri'ed, „ Wat«r-S_tned Leaves (69) (MLRA 1,2, 4A.9IKI 4iEt) __ Drainage P$ttern»{510) . Dry-Season Water Table (C2) , Saturation Visible on Aerial Imagery (C0) . Geomorphlc Position (D2) Shallow Aquitard(D3) FAONeutrafTest(05) __ Raised Art Mounds (D6) (LRR A) , ,, Frost-Heave Hummocks (D?) Field Observations: Surface Water Present? Water Table Present? Saturation Present? (includes capiflary frfrige) Wetland Hydrology Present? Yos _. Describe Recordwl Data (stream'gaugft, moniforinb Weil,' aerial photos, previous' (napewione). tf available; US Army Corps of engineers Western Mountains. Valleys, and Coast-Interim Version North Ridgeview Estates PlatHearing Examiner Packet Page 381 of 422 wtf- A-/c A 1 WETLAND DETERMINATION DATA PORM - Western Mountains. Valleys, and Coast Region Pm^/flt,: X^Cp^-j ~ PJg^^^JcHWCoumv: /\K\>V f_ Sampling Dale:. S-1(>'tJ* Anpiicmnmwrnr; , __ State: _____ Sampling Point:. Invasrigatorfs): _ H/<f- \\,. Section, Township, Rang*: , , ., ... Landform thittsiopa. terrace, etc):. Subnsgion (LRR): ________ Soil Map Unit Name: . Lat_ . Local relief (concave, convex, none),•_ __________ Long: . NWIclassKlcatton:, „ Slope I*):. . Datum: Are climate/ hydrologle conditions on the site typical for this time of year? Yes ___No_ (If no, explain in Remarks.) Are Vegetation _, Soli . or Hydrology ____ signlficentiy disturbed? Are -Normal Circumstances' present? Yas S~ No Are Vegetation , SoH , or Hydrology naturally probiemalic? (if needed, explain any answers in Remarks,) SUMMARY OF FIND1NS5S - Attach site map showing sampling point locations, transeots, important features, ot«. Hydrophytie Vegetation Present? Hydrio Soil Present? Wetland Hydrology Presemi? Yes_ Yes Yes_ _5_'No 2l>o No la the sampled Area within a Wotland? Ye* No , Remark*. VEGETATION -.Us* scientific names of plants. Absolute Dominant Indicator It Cover Spqckts? Status Tree Stratum (Plotsfee:. 1. 2. 3. _ 4. _) SapllnofShrub Stratum (Plotctie:. 1 _____ 2 3 A 5. Hemstrahjm (Piot5__ ]_____-__± OBL specie^ _ FACW species , FAC species _ FACU species . PL species . Column Totals: Woc-v.Vjne Stratum (Plot size:,. 1-% Bare Ground in Herb Stratum _ Dominance Test ww^sheefc Number of Dominant Spedes ^SaTAreOBLTFACW. Pf FAC;~ TotoJ Number of Dominant Spedes Across All Strata: Percent pf Dominant Spades That Are OBL, FACW. Or FAC: -(A)— <B> (Am) Prevalence index" worksheet: Totals Cover of: _ .Multiply bv; . . x3a. . x4tt„ , xS v _ .(A) _ ilence Index * B/A » , (B) Hyo>ophyt_ Vegetation mtflcatomj ,_<Dpminancq Test Is >90% Prevatence Index is 33.Q' MorprTOloalcatAdar^ationa^PrwWesupporilng data in Remarks or on a separate sheet) Wetland Non-Vascular Plants4 Problematic Hydrophyte 'Indicators ctfhydMc soil arid wetland hydrology must be present, vnfass disturbed or problematic. Hydrophytio V<_etstk>o Present? Yes. US Army Corps of Engineers Western Mountains', Valleys, and Coast - Interim Version y>PL) SOIL -Sampling Point; Profile Descriptton: (Describe to the depih needed to doegmerrt tne lotf Depth ,,.... ,. Matrix ., ,, ,., , ,, . Rpg"oxFeatures ,. L , . •flWrttfltf ^MS^iSS^U, _j3Wff,fo>P'*0 m % „ Tml~ •• M>r , ,. Ipm:, Remarks Vype,;, C^oncentratton. p^Dei^c^^f^iM^educed Matrix, CS*Covered orCoa,ted Sand Qrelns. 'Location:. P_=Pore Lining. M=ivWi<, indicator* for pro-lematic Hydrlc SollsV" 2cmArruck(AtO) Red Parent Material (TF2) Other (Explain bi Remarks) indicators of hydrophytic vegetation and wetland hydrology must be present, unless disturbed or probiemalic Hydrio Soil Indicators: (Applicable to all LRRs, yntess ojharwtaa noted.) HWosot (A1) Hlstlc Epipeddn (A2) Stack Histic (A3) __ Hydrogen Sulfide <A4) , . Depleted Below Dark Surface (A11) . Thick Dark Surface (A12) Sandy Mucky Mineral (81) _ Sandy Gloved Matrix (54) Restr^ctrve Lay er (if jH^sAnt): -TVpa; TT, .„._ Sandy Redox (SS) Stripped Matrix (SO) Loamy Mucky Mmeral (F1) (except MLRA 1 , . Loamy Gteyed Malrix (FZ) .(Japleted Matrix (F3) . "^RedoxDarkSLtrtace(FO) Dept«f*^ Cftrk Surface (F7) _ Redox Depressions (F8) Depth (Inches); _ Hydric Soil Present? Yea „ KYOROLOGY Wetland Hydrology Indicators: PTl,n]f?fy,1nW?^ frrtfnfmum pf opp r^uirgd; checH,a|l tngt aiRly),, Surface Water (A1) High Water Table (A2) , „ Saturation (A3) WaterMarks(BI) SedimenlDeposits(B2) „ Drift Oeposfts (B3) ___. Algal Mat or Crust (B4) ,, Iron Deposits (B5) S<m_ce Soil Crscks (BQ) Inundation v/sibfe on Aerial imagery (87) $pare©tyVeg^t9redCon_veSi4tface(BS) . Water-Stained Leaves (89) (axcapt MLRA 1,2,4^*^46) . sail Crust (B11) . Aquatic fnvertebrates (B13) . Hydrogen Sutfide Odor (C1) . Oxidized Rhlzosphereg along Living Roots (C3) . Presence of Reduced iron (04) , Recent Iron Reduction in Tilled SOIIB (CO) . Slurried or Stressed Plants (D1) (LRR A) . Other (Explain In Remarks} Secondary Indicators f3.gr, more feqtfred,, Walar-Sialned Leaves (B9j (MLRA 1,2, 4A, and 46} d Drainage Patlems(BIO) Dry^Season Water Table (02) , Saturation Visible on Aerial Imagery (C8) GeomorphfC Position (02) __ Shallow Aquitard(D3) _ FAONauiral Test (OS) __ Raised Anl Mounds (D6) (LRR A) Frost-Heave Hummocks (0/) Field Observatlona: Surface Watfer Present? Water Table Present? Saturation Presarif? (includes canWary fringe^ Wetland Hydrology Present? Yes j bascribfl Recorded 5aia'(stream rjaufl'e, moWtoring welt, aed'ai i^tcw,-prevtous inspeciionfl), if available: US Army Corps of Engineers Western Mountains, Vailoyo, and Coast- Interim Version North Ridgeview Estates PlatHearing Examiner Packet Page 382 of 422 Wetland name or number WETLAND RATING FORM - WESTERN WASHINGTON Version 2 - Updated July 2006 to increase accuracy and reproducibility among users Updated Oct 2008 with tie new WDFW definitions for priority habitats Name of wetland (if known): (A-f^*-^ ff/c Rated by_ SEC Date of site visit: Trained by Ecology? Yes_No Date of training_ TWNSHP:. RNGE: . Is S/T/R in Appendix D? Yes No Map of wetland unit: Figure Estimated size 3 SUMMARY OF RATING Category based on ITOCTJCfNS provided by wetland i n ni s:rv Category I = Score >=70 Category H = Score 51-69 Category _ = Score 30-50 Category IV = Score < 30 Score for Water Quality Functions Score forHydrologic.unctions Score for Habitat Functions / 4 TOTAL score for Functions 10 Category based on SPECIAL CHARACTERISTICS of wetland I IT Does not Apply ' Final Category (choose the "highest" category from above) mBaii.6LTTnirti i "Special,* V, Chau tcfujstics „ „ _ s \ jj Usui tin Krilllli: -a* Eotuaiine Deprcssional y Natural Heritage Wetland Riverine Bog Lake-fringe Mature Forest Slope Old Growth Forest Flats Coastal Lagoon Freshwater Tidal Interdunal None of the above ,dheck if unit has multiple HGM classes present Wetland Rating Form-western Washington 1 version 2 To be used with Ecology Publication 04-06-025 August 2004 Wetland name or number Does the wetland unit being rated meet any of the criteria below? If you answer YES to any of the questions below you will need to protect the wetland according to the regulations regarding the special characteristics found in the wetland. n SP1. Has the wetland unit been documented as a habitat for any Federally listed Ttveatened or Endangered animal or plant species (T/E species)? For the purposes of this rating system, "documented" means the wetland is on the appropriate state or federal database. SP2. Has the wetland unit been documented as habitat for any State listed Tlireatened or Endangered animal species? For the purposes of this rating system, "documented" means the wetland is on the appropriate state database. Note: Wetlands with State listed plant species are categorized as Category I Natural Heritage Wetlands (see p. 19 of data form). y SP3. Does the wetland unit contain individuals of Priority species listed by the WDFW for the state? SP4. Does the wetland unit have a local significance in addition to its functions'! For example, the wetland has been identified in the Shoreline Master Program, the Critical Areas Ordinance, or in a local management plan as having special significance. To complete the next part of the data sheet you will need to determine the Hvdroseomorphic Class of the wetland being rated. The hydrogeomorphic classification groups wetlands into those that function in similar ways. This simplifies the questions needed to answer how well the wetland functions. The Hydrogeomorphic Class of a wetland can be determined using the key below. See p. 24 for more detailed instructions on classifying wetlands. Wetland Rating Form-western Washington 1 version 2 Updated with new WDFW definitions Oct 2008 August 2004 North Ridgeview Estates PlatHearing Examiner Packet Page 383 of 422 Wetland name or number '^"U^-Gassification of Wetland Units in Western Washington If the hydrologic criteria listed in each question do not apply to the entire unit being . •, . rated, you probably have a unit with multiple HGM classes. In this case, identify which hydrologic criteria iu questions lr7 apply, and go to Questions, : > 1. Arethe water levels in the entire unit usually controlled by tides (i.e. except during floods)? 30~-gotc^ YES-the wetland class is Tidal Fringe If yes, is the salinity of the water during periods of annual low flow below 0.5 ppt (parts per thousand)? YES - Freshwater Tidal Fringe NO - Saltwater Tidal Fringe (Estuarine) If your wetland can be classified as a Freshwater Tidal Fringe use the forms for Riverine wetlands. If it is Saltwater Tidal Fringe it is rated as an Estuarine wetland Wetlands that were called estuarine in the first and second editions of the rating system are called Salt Water Tidal Fringe in the Hydrogeomorphic Classification. Estuarine wetlands were categorized separately in the earlier editions, and this separation is being kept in this revision. To maintain consistency between editions, the term "Estuarine" wetland is kept. Please n6Te,TibWver,lhat me cTiafac^ estuarine wetlands have changed (see p. ). 2. The entire wetland unit is flat and precipitation is the only source (>90%) of water to it. Grojmdmter-and surface water runoff are NOT sources of water to the unit. NO - go tc>3^> YES - The wetland class is Flats E^our wetland can be classified as a "Flats" wetland, use the form for Depresslonal wetlands. 3. Does the entire wetland unit meet both of the following criteria? The vegetated part of the wetland is on the shores of a body of permanent open water (without any vegetation on the surface) at least 20 acres (8 ha) in size; Atleast 30% of the open water area is deeper than 6.6 ft (2 m)? NO - gojpj^ YES - The wetland class is Lake-fringe (Lacustrine Fringe) 4rDoes the erjtire wetland unit meet all of the following criteria? "^T-he wetland is on a slope (slope can be very gradual), 1/ The water flows through the wetland in one direction (unidirectional) and usually comes from seeps. It may flow subsurface, as sheetflow, or in a swale without ^distinct banks. The water leaves the wetland without being impounded? NOTE: Surface water does not pond in these type of wetlands except occasionally in very small and shallow depressions or behind hummocks (depressions are usually <3ft diameJer-andless-tlwn-lffoatjdeepX NO-go to 5 YES -The wetland class is JIope~~-Wetland Rating Form- western Washington. 3 version 2 Updated with new WDFW definitions Oct. 2008 August 2004 Wetland name or number 5. Does the entire wetland unit meet all of the following criteria? The unit is in a valley, or stream channel, where it gets inundated by overbank flooding from that stream or river The overbank flooding occurs at least once every two years. NOTE: The riverine unit can contain depressions that are filled with water when the river is not flooding. NO - go to 6 YES - The wetland class is Riverine 6. Is the entire wetland unit in a topographic depression in which water ponds, or is saturated to the surface, at some time during the year. This means that any outlet, if present, is higher than the interior of the wetland. <CI____Q_go-t8 7 YES - The wetland class is Depressional 7. Is the entire wetland unit located in a very flat area with no obvious depression and no overbank flooding. The unit does not pond surface water more than a few inches. The unit seems to be maintained by high groundwater in the area. The wetland may be ditched, but has no obvious natural outlet. NO - go to 8 YES - The wetland class is Depressional -8r-Your-wetlandunitseems to-be diffioulttoclassify.and-prob ably contains., several differentHGM clases. For example, seeps at the base of a slope may grade into a riverine floodplain, or a small stream within a depressional wetland has a zone of flooding along its sides. GO BACK AND IDENTIFY WHICH OF THE HYDROLOGIC REGIMES DESCRIBED IN QUESTIONS 1-7 APPLY TO DIFFERENT AREAS IN THE UNIT (make a rough sketch to help you decide). Use the following table to identify the appropriate class to use for the rating system if you have several HGM classes present "within your wetland. NOTE: Use this table only if the class that is recommended in the second column represents 10% or more of the total area of the wetland unit being rated. If the area of the class listed in column 2 is less than 10% of the unit; classify the wetland using the class that represents more than 90% of the total area. Slope + Riverine Riverine Slope + Depressional Depressional Slope + Lake-fringe Lake-fringe Depressional + Riverine along stream within boundary Depressional Depressional + Lake-fringe Depressional Salt Water Tidal Fringe and any other class of freshwater wetland Treat as ESTUARINE under wetlands with special characteristics If you are unable still to determine which of the above criteria apply to your wetland, or if you have more than 2 HGM classes within a wetland boundary, classify the wetland as Depressional for the rating. Wetland Rating Fo rm - western Washington 4 version 2 Updated with new WDFW definitions Oet 2008 August 2004 North Ridgeview Estates PlatHearing Examiner Packet Page 384 of 422 Wetland name or number |), IK | i I'ssion'.MMnd-TlaiS \\«.-tlruiiN ..» «-*yf*> •» -vii v_ct ILt i It-* | '1 li'l1 l at- » vTS.* D 1. Does the wetland unit have the potential to improve water quality? (see p.38) D 1.1 Characteristics of surface water flows out of the wetland: Unit is a depression with no surface water leaving it (no outlet) points-^ Unit has an intermittently flowing, OR highly constricted permanently flowing outlet ^pomts^jj) Unit has an unconstricted, or slightly constricted, surface outlet (permanently flowing) points = 1 Unit is a(flat" depression (Q. 7 on key), or in the Flats class, with permanent surface outflow and no obyious natural outlet and/or outlet is a man-made ditch points - 1 (If ditch is not permanently flowing treat unit as "intermittently flowing ") Provide photo or drawing Figure _ 1 S 1.2 The soil 2 inches below the surface (or duff layer) is clay or organic (useNRCS definitions) YES Minis. NO points = (C D 1.3 Characteristics of persistent vegetation (emergent, shrub, and/or forest Cowardin class) Wetland has persistent, ungrazed, vegetation > = 95% of area points = 5 -Wetland has persistent, ungrazed, vegetations = 1/2-of area ^pSffisj=3j3 Wetland has persistent, ungrazed vegetation > = 1/10 of area ^oittBf=l Wetland has persistent, ungrazed vegetation <1/10 of area points = 0 Map of Cowardlri vegetation classes Figure. D1.4 Characteristics of seasonal ponding or inundation. This is the area ofthe wetland unit that Is ponded for at least 2 months, but dries out sometime during the year. Do not count the area that is permanently ponded Estimate area as the average condition 5 out of lOyrs. Area seasonally ponded is > K total area of wetland points = 4 Area seasonally ponded is > V4 total area of wetland fSomts = 2~\ Area seasonally ponded is<% total area of wetland points = 0 _____ _____ Map of Hydroperiods Total for D 1 Add the points in the boxes above D 2. Does the wetland unit have the opportunity to Improve water quality? Answer YES if you know or believe there are pollutants in groundwater or surface water coming into the wetland that would otherwise reduce water quality in streams, lakes or groundwater downgradient from the wetland. Note which of the following conditions provide the sources ofpollutants. A unit may have pollutants coming from several sources, but any single source would qualify as opportunity. •— Grazing in the wetland or within 150 ft -^^tjntreated stormwater discharges to wetland — Tilled fields or orchards within 150 ft of wetland — A stream or culvert discharges into wetland that drains developed areas, residential areas, ^farmed fields, roads, or clear-cut logging •— Residential, urban areas, golf courses are within 150 ft of wetland — Wetland is fed by groundwater high in phosphorus or nitrogen Othe NO multiplier is 1 Figure ___ :zi: (see p. 44) multiplier 2L D TOTAL - Water Quality Functions Multiply the score from Dl by D2 Addscore to table on p. 1 Wetland Rating Form-western Washington 5 version 2 Updated with new WDFW definitions Oct 2008 August 2004 Wetland name or number D Depressional andBlafs Wetlands ~HY^0t6GlC?T^CTi;0HS - Indicators thatthe-wetlandmqft.fujipttons to jeducg flooding affrfstteam degradation \D 3. Does the wetland unit have the potential to reduce flooding and erosion? Points (onhkl-sawfr ^ * } (seep.46) D D D 3.1 Characteristics of surface water flows out of the wetland unit Unit is a depression with no surface water leaving it (no outlet) points = 4 Unit has an intermittently flowing, OR highly constricted permanently flowing outlet <^gomts=^' Unit is a "flat" depression (Q. 7 on key), or in the Flats class, with permanent surface ou&low and no obvious natural outlet and/or outlet is a man-made ditch points = 1 (If ditch is not permanently flowing treat unit as "intermittently flawing") Unit has an unconstricted, or slightly constricted, surface outlet (permanently flowing) points = 0 D 3.2 Depth of storage during wet periods Estimate the height ofponding above the bottom of the outlet. For units with no outlet measure from the surface ofpermanent water or deepest part (ifdry). Marks of ponding are 3 ft or more above the surface or bottom of outlet points = 7 The wetland is a "headwater" wetland" points = 5 Marks of ponding between 2 ft to < 3 ft from surface or bottom of outlet points = 5 Marks are at least 0.5 ft to < 2 ft from surface or bottom of outlet points = 3 Unit is flat (yes to Q. 2 or Q. 7 on key) but has small depressions on the surface that trap water points = 1 Marks of ponding less than 0.5 ft D D D D 3.3 Contribution of wetland unit to storage in the watershed Estimate the ratio of the area of upstream basin contributing surface water to the wetland to the area of the wetland unit itself. The area of the basin is less than 10 times the area of unit points = 5 The area of the basin is 10 to 100 times the area of the unit rjjointsgjff The area of the basin is more than 100 times the area of the unit points = 0 Entire unit is in the FLATS class points = 5 Total for D 3 Add lite points in the boxes above I D 4. Does the wetland unit have the opportunity to reduce flooding and erosion? Answer YES if the unit is in a location in the watershed where the flood storage, or reduction in water velocity, it provides helps protect downstream property and aquatic resources from flooding or excessive and/or erosive flows. Answer NO if the water coming into the wetland is controlled by a structure such as flood gate, tide gate, flap valve, reservoir etc. OR you estimate that more than 90% of the water in the wetland is from groundwater in areas where damaging groundwater flooding does not occur. Note which of the following indicators ofopportunity apply. —^Vyjetland is in a headwater of a river or stream that has flooding problems — Wetland drams to a river or stream that has flooding problems •— Wetland has no outlet and impounds surface runoff water that might otherwise flow into a river or stream that has flooding problems — Other YES (see p. 49) p^iplier ij^l -1 NO multiplier is 1 multiplier - Hydrologic Functions Multiply the score from D 3 by D 4 Addscore to table on p. 1 D Wetland Rating Form - western Washington 6 version 2 Updated with new WDFW definitions Oct 2008 August 2004 North Ridgeview Estates PlatHearing Examiner Packet Page 385 of 422 H1. Does the wetland unit have the potential to provide habitat for many species? H 1.1 Veeetation structure (see o. 72) Check the types of vegetation classes present (as defined by Cowardin)- Size threshold for each class is 'A acre or more than 10% of the area if unit is smaller than 2.5 acres. Aquatic bed _t_Emergent plants Scpub/shrub (areas where shrubs have >30% cover) ^-Forested (areas where trees have >30% cover) If the unit has a forested class check if: ___fhe forested class has 3 out of 5 strata (canopy, sub-canopy, shrubs, herbaceous, moss/ground-cover) that each cover 20% within the forested polygon Add the number ofvegetation structures that qualify. If you have: 4 structures or more points = 4 Map of Cowardin vegetation classes 3 structures p6mts = 2'^) 2 structures points-=-l 1 structure —" points''0 Figure -J2--H 1.2. Hvdroperiods (see p. 73) Check the t}pes of mater regimes (hydroperiods) present within the wetland The water regime has to cover more than 10% of the wetland or V* acre to count, (see text for descriptions of hydroperiods) Permanently flooded or inundated 4 or more types present points = 3 •^Seasonally flooded or inundated 3 types present p^intsj^Jf* Occasionally flooded or inundated 2 types present point =1 ^"Saturated only 1 type present points = 0 , Permanently flowing stream or river in, or adjacent to, the wetland Seasonally flowing stream in, or adjacent to, the wetland Lake-fringe wetland = 2 points Freshwater tidal wetland" 2 points Map of hydroperiods Figure H 1.3. Richness of Plant Species (seep. 75) Count the number of plant species in the wetland that cover at least 10 ft2, (different patches of the same species can be combined to meet the size threshold) You do not have to name the species. Do not include Eurasian Milfoil, reed canarygrass, purple loosestrife, Canadian Thistle If you counted: > 19 species pointsj_2 List species below if you want to: 5-19 species pCints <5 species pSints^O \ Total for page Wetland Rating Form -western Washington 13 version 2 Updated with new WDFW definitions Oct 2008 August 2004 Wetland name or number H 1.4. Interspersion of habitats (see p. 76) Decide from the diagrams below whether interspersion between Cowardin vegetation classes (described in H 1.1), or the classes and unvegetated areas (can include open water or mudflats) is high, medium, low, or none. [riparian braided channels] _fiigh~ 3 points NOTE: If you have four or more classes or three vegetation classes and open water the rating is always "high". Use map of Cowardin vegetation classes H 1.5. Special Habitat Features: (see p. 77) Check the habitat features that are present in the wetland The number ofchecks Is the number ofpoints you put Into the next column. ___Large, downed, woody debris within the wetland (>4in. diameter and 6 ft long). ___Stonding snags (diameter at the bottom > 4 inches) in the wetland Undercut banks are present for at least 6.6 ft (2m) and/or overhanging vegetation extends at least 33 ft (lm) over a stream (or ditch) in, or contiguous with the unit, for at least 33 ft (10m) Stable steep banks of fine material that might be used by beaver or muskrat for denning (>30degree slope) OR signs of recent beaver activity are present (cut shrubs or trees that have not yet turned grey/brown) At least Vi acre of thin-stemmed persistent vegetation or woody branches are present in areas that are permanently or seasonally inundated (structures for egg-laying by amphibians) Invasive plants cover less than 25% of the wetland area in each stratum of plants NOTE: The 20 % stated in early printings of the manual on page 78 is an error. H1. TOTAL Score - potential for providing habitat Add the scores from Hl.l, H1.2, H1.3, H1.4, H1.5 Comments — — —i ..2.J Wetland Rating Form -western Washington 14 version 2 Updated with new WDFW definitions Oct 2008 August 2004 North Ridgeview Estates PlatHearing Examiner Packet Page 386 of 422 Wetland name or number H 2. Does the wetland unit have the opportunity to provide habitat for many species? H 2.1 Buffers (seep. SO) Choose the description that best represents condition of buffer ofwetland unit. The highest scoring criterion that applies to the wetland is to be used in the rating. See text for definition of "undisturbed " — 100 m (330ft) of relatively undisturbed vegetated areas, rocky areas, or open water >95% of circumference. No structures are within the undisturbed part of buffer, (relatively undisturbed also means no-grazing, no landscaping, no daily human use) Points = S — 100 m (330 ft) of relatively undisturbed vegetated areas, rocky areas, or open water > 50% circumference. Points = 4 •— 50 m (170ft) of relatively undisturbed vegetated areas, rocky areas, or open water >95% circumference. Points = 4 — 100 m (330ft) of relatively undisturbed vegetated areas, rocky areas, or open water > 25% circumference,. Poults = 3 — 50 m (170ft) of relatively undisturbed vegetated areas, rocky areas, or open water for > 50% circumference. Points = 3 If buffer does not meet any of the criteria above — No paved areas (except paved trails) or buildings within 25 m (80ft) of wetland > 95% circumference. Light to moderate grazing, or lawns areCSK. ~" wants = 2*^5^ •—• No paved areas or buildings within 50m of wetland for >50% circumference. Light to moderate grazing, or lawns are OK. Points = 2 — Heavy grazing in buffer. Points = 1 •— Vegetated buffers are <2m wide (6.6ft) for more than 95% of the circumference (e.g. tilled fields, paving, basalt bedrock extend to edge of wetland Points = 0. — Buffer does not meet any of the criteria above. Points = 1 Aerial photo showing buffers H 2.2 Corridors and Connections (seep. 81) H 2.2.1 Is file wetland part of a relatively undisturbed and unbroken vegetated corridor (either riparian or upland) that is at least 150 ft wide, has at least 30% cover of shrubs, forest or native undisturbed prairie, that connects to estuaries, other wetlands or undisturbed uplands that are at least 250 acres in size? (dams in riparian corridors, heavily used gravel roads, paved roads, are considered breaks in the corridor). YES = 4 points (go to H 2.3) NO = go to H 2.2.2 H 2.2.2 Is the wetland part of a relatively undisturbed and unbroken vegetated corridor (either riparian or upland) that is at least 50ft wide, has at least 30% cover of shrubs or forest, and connects to estuaries, other wetlands or undisturbed uplands that are at least 25 acres in size? OR a Lakc-frlnge wetland, if it does not have an undisturbed corridor as in the question above? YES =2 points (go to H 2.3) NO = H 2.2,3 H 2.2.3 Is the wetland: within 5 mi (8km) of a brackish or salt water estuary OR "•""^within 3 mi of a large field or pasture (>40 acres) OR ^vithinjjnijf-a-lake greater than 20 acres? ttlpP NO = 0 points Total for page_ 3 Wetland Rating Form -western Washington 15 version 2 Updated with new WDFW definitions Oct 20D8 August 2004 Wetland name or number H 2.3 Near or adiacentto other priority habitats listed bv WDFW (see new and complete descriptions of WDFW priority habitats, and the counties bt which they can be found, in the PHS report http://wdfiv.wa. eov/hab/ohshsi.htm) Which of the following priority habitats are within 330ft (100m) of the wetland unit? NOTE: the connections do not have lobe relatively undisturbed Aspen Stands: Pure or mixed stands of aspen greater than 0.4 ha (1 acre). Biodiversity Areas and Corridors: Areas of habitat that are relatively important to various species of native fish and wildlife (full descriptions in WDFW PHS report p. 152). Herbaceous Balds: Variable size patches of grass and forbs on shallow soils over bedrock. Old-growth/Mature forests: (Old-growth west of Cascade cresf) Stands of at least 2 tree species, forming a multi-layered canopy with occasional small openings; with at least 20 trees/ha (8 trees/acre) > 81 cm (32 in) dbh or > 200 years of age. (Mature forests'! Stands with average diameters exceeding 53 cm (21 in) dbh; crown cover may be less that 100%; crown cover may be less that 100%; decay, decadence, numbers of snags, and quantity of large downed material is generally less than that found in old-growth; 80 - 200 years old west of the Cascade crest. _Oregon white Oak: Woodlands Stands of pure oak or oak/conifer associations where canopy coverage of the oak component is important (full descriptions in WDFW PHS / report p. 158). -s Riparian: The area adjacent to aquatic systems with flowing water that contains elements of b^tb"aayauewdTeiresW Westslde Prairies: Herbaceous, non-forested plant communities that can either take the form of a dry prairie or a wet prairie (full descriptions in WDFW PHS report p. 161). Instream: The combination of physical, biological, and chemical processes and conditions that interact to provide functional life history requirements for instream fish and wildlife resources. Nearshore: Relatively undisturbed nearshore habitats. These include Coastal Nearshore, Open Coast Nearshore, and Puget Sound Nearshore. (full descriptions of habitats and the definition of relatively undisturbed, are in WDFftr report: pp. 167-169 and glossary in AppendixA). Caves: A naturally occurring cavity, recess, void, or system of interconnected passages under the earth in soils, rock, ice, or other geological formations and is large enough to contain a human. Cliffs: Greater than 7.6 m (25 ft) high and occurring below 5000 ft. Talus: Homogenous areas of rock rubble ranging in average size 0.15 - 2.0 m (0.5 - 6.5 ft), composed of basalt, andesite, and/or sedimentary rock, including riprap slides and mine tailings. May be associated with cliffs. Snags and Logs: Trees are considered snags if they are dead or dying and exhibit sufficient decay characteristics to enable cavity excavation/use by wildlife. Priority snags have a diameter at breast height of > 51 cm (20 in) in western Washington and are > 2m (6.5 ft) in height. Priority logs are > 30 cm (12 in) in diameter at the largest end, and > 6 m (20 ft) long. If wetland has 3 or more priority habitats = 4 points If wetland has 2 priority habitats = 3 points If wetland has 1 priority habitat=1 point No habitats = 0 points Note: All vegetated wetlands are by definition a priority habitat but are not included in this list. Nearby wetlands are addressed In question H 2.4) Wetland Rating Form-western Washington 16 version2 Updated with new WDFW definitions Oct 2008 August 2004 North Ridgeview Estates PlatHearing Examiner Packet Page 387 of 422 Wetland name or number h H 2.4 Wetland Landscape (choose the one description of the landscape around the wetland that best fits) (seep. 84) There are at least 3 other wetlands within 'A mile, and the connections between them are relatively undisturbed (light grazing between wetlands OK, as is lake shore with some boating, but connections should NOT be bisected by paved roads, fill, fields, or other development. points = 5 The wetland is Lake-fringe on a lake with little disturbance and there are 3 other lake-fringe wetlands within 14 mile points = 5 There are at least 3 other wetlands within 14 mile, BUT the connections between them are disturbed (fpomts =___^> The wetland is Lake-fringe on a lake with disturbance and there are 3 other lake-fringe wetland within V4 mile points = 3 There is at least 1 wetland within 14 mile. points = 2 There are no wetlands within 14 mile. points = 0 2 H 2. TOTAL Score - opportunity for providing habitat Add the scores.from H2.1.H2.2, H2.3, B2.4 7 TOTAL for H 1 from page 14 Total Score for Habitat Functions - add the points for H1, H 2 and record the result on P.l /a Wetland Rating Form -western Washington 17 version 2 Updated with new WDFW definitions Oct 2008 August 2004 Wetland name or number CATEGORIZATION BASED ON SPECIAL CHARACTERISTICS Please determine if the wetland meets the attributes described below and circle the appropriate answers and Category. Wetland Type Check off any criteria that apply to the we/land. Circle the Category when the appropriate criteria arc met. .-'v.-.,:" Category SC 1.0 Estuarine wetlands (seep. SO) Does the wetland unit meet the following criteria for Estuarine wetlands? — The dominant water regime is tidal, — Vegetated, and ^< •— With a salinity greater than 0.5 ppt. YES = Go to SC 1.1 NO SC 1.1 Is the wetland unit within a National Wildlife Refuge, National Park, National Estuary Reserve, Natural Area Preserve, State Park or Educational, Environmentaij-or Scientific-Reserve designated-under-WAG332-30-151? YES = Category I NO go to SC 1.2 Cat I SC 1.1 Is the wetland unit within a National Wildlife Refuge, National Park, National Estuary Reserve, Natural Area Preserve, State Park or Educational, Environmentaij-or Scientific-Reserve designated-under-WAG332-30-151? YES = Category I NO go to SC 1.2 SC 1.2 Is the wetland unit at least 1 acre in size and meets at least two of the following three conditions? YES = Category I NO = Category II •—• The wetland is relatively undisturbed (has no diking, ditching, filling, cultivation, grazing, and has less than 10% cover of non-native plant species. If the non-native Spartina spp. are the only species that cover more than 10% of the wetland, then the wetland should be given a dual rating (T/Tf). The area of Spartina would be rated a Category II while the relatively undisturbed upper marsh with native species would be a Category I. Do not, however, exclude the area of Spartina in determining the size threshold of 1 acre. — At least VA of the landward edge of the wetland has a 100 ft buffer of shrub, forest, or un-grazed or un-mowed grassland. •— The wetland has at least 2 of the following features: tidal channels, depressions with open water, or contiguous freshwater wetlands. Cat. I Cat II Dual rating mi Wetland Rating Form -western Washington 18 version 2 Updated with new WDFW definitions Oct 2008 August 2004 North Ridgeview Estates PlatHearing Examiner Packet Page 388 of 422 Wetland name or number SC2.0 Natural Heritage Wetlands (seep. 87) Natural Heritage wetlands have been identified by the Washington Natural Heritage Program/DNR as either high quality undisturbed wetlands or wetlands that support state Threatened, Endangered, or Sensitive plant species. SC 2.1 Is the wetland unit being rated in a Section/Township/Range that contains a Natural Heritage wetland? (this question is used to screen out most sites before you need to contact M'NBP/DNR) S/T/R information from Appendix D or accessed from WNHP/DNR web site YES - contact WNHP/DNR (see p. 79) and go to SC 2.2 NO SC 2.2 Has DNR identified the wetland as a high quality undisturbed wetland or as or as a site with state threatened or endangered plant species? YES = Category I NO not a Heritage Wetland Cat I SC 3.0 Bogs (seep. 87) Does the wetland unit (or any part of the unit) meet both the criteria for soils and vegetation in bogs? Usethe key belowto identify if the wetland isabog.-Ifyou answer yes you will still need to rate the wetland based on its functions. 1. Does the unit have organic soil horizons (i.e. layers of organic soil), either peats or mucks, that compose 16 inches or more ofthe first 32 inches of the soil profile? (See Appendix B for a field kev to identify organic soils)? Yes -go to Q. 3 (^Ro~- go\o%2 "> 2. Does the unit have organic soTlsTeTtEerpeats or mucks that are less than 16 inches deep over bedrock, or an impermeable hardpan such as clay or volcanic ash, or that are floating on a lake^er-porid? • Yes - go to Q. 3 C No - Is not a bog for purpose of rating^ 3. Does the unit have more than 70% cover^fmosses-at-groundlOTeT, AND other plants, if present, consist ofthe "bog" species listed in Table 3 as a significant component ofthe vegetation (more than 30% ofthe total shrub and herbaceous cover consists of species in Table 3)7 Yes - Is a bog for purpose of rating No - go to Q. 4 NOTE: If you are uncertain about the extent of mosses in the understory you may substitute that criterion by measuring the pH ofthe water that seeps into a hole dug at least 16" deep. If the pH is less than 5.0 and the "bog" plant species in Table 3 are present, the wetland is a bog. 1. Is the unit forested (> 30% cover) with sitka spruce, subalpine fir, western red cedar, western hemlock, lodgepole pine, quaking aspen, Englemann's spruce, or western white pine, WITH any ofthe species (or combination of species) on the bog species plant list in Table 3 as a significant component ofthe ground cover (> 30% coverage of the total shrub/herbaceous cover)? 2. YES = Category I No Is not a bog for purpose of rating Cat. I Wetland Rating Form - western Washington 19 version 2 Updated with new WDFW definitions Oct 2008 August 2004 Wetland name or number SC 4.0 Forested Wetlands (seep. 90) Does the wetland unit have at least 1 acre of forest that meet one of these criteria for the Department of Fish and Wildlife's forests as priority habitats? If you answer yes you will still need to rate the wetland based on its functions. — Old-growth forests: (west of Cascade crest) Stands of at least two tree species, forming a multi-layered canopy with occasional small openings; with at least 8 trees/acre (20 trees/hectare) that are at least 200 years of age OR have a diameter at breast height (dbh) of 32 inches (81 cm) or more. NOTE: The criterion for dbh is based on measurements for upland forests. Two-hundred year old trees in wetlands will often have a smaller dbh because their growth rates are often slower. The DFW criterion is and "OR" so old-growth forests do not necessarily have to have trees of this diameter. — Mature forests: (west ofthe Cascade Crest) Stands where the largest trees are 80 - 200 years old OR have average diameters (dbh) exceeding 21 inches (53cm); crown cover may be less that 100%; decay, decadence, numbers of snags.and quantity of large downed material is generally less than that found in old-growth. YES = Category I NO __fot a forested wetland with special characteristics SC 4.0 Forested Wetlands (seep. 90) Does the wetland unit have at least 1 acre of forest that meet one of these criteria for the Department of Fish and Wildlife's forests as priority habitats? If you answer yes you will still need to rate the wetland based on its functions. — Old-growth forests: (west of Cascade crest) Stands of at least two tree species, forming a multi-layered canopy with occasional small openings; with at least 8 trees/acre (20 trees/hectare) that are at least 200 years of age OR have a diameter at breast height (dbh) of 32 inches (81 cm) or more. NOTE: The criterion for dbh is based on measurements for upland forests. Two-hundred year old trees in wetlands will often have a smaller dbh because their growth rates are often slower. The DFW criterion is and "OR" so old-growth forests do not necessarily have to have trees of this diameter. — Mature forests: (west ofthe Cascade Crest) Stands where the largest trees are 80 - 200 years old OR have average diameters (dbh) exceeding 21 inches (53cm); crown cover may be less that 100%; decay, decadence, numbers of snags.and quantity of large downed material is generally less than that found in old-growth. YES = Category I NO __fot a forested wetland with special characteristics Cat I SC 5.0 Wetlands In Coastal Lagoons (seep. 91) Does the wetland meet all ofthe following criteria of a wetland in a coastal lagoon? — The wetland lies in a depression adjacent to marine waters that is wholly or partially separated from marine waters by sandbanks, gravel banks, shingle, or, less frequently, rocks — The lagoon in which the wetland is located contains surface water that is saline or brackish (> 0.5 ppt) during most ofthe year in at least a portion ofthe lagoon (needs to be measuredneatyihe bottom) YES = Go to SC 5.1 NO not a wetland in a coastal lagoon SC 5.1 Does the wetland meets all ofthe following three conditions? — The wetland is relatively undisturbed (has no diking, ditching, filling, cultivation, grazing), and has less than 20% cover of invasive plant species (see list of invasive species on p. 74). — At least Vt ofthe landward edge ofthe wetland has a 100 ft buffer of shrub, forest, or un-grazed or un-mowed grassland. — The wetland is larger than 1/10 acre (4350 square feet) YES = Category I NO = Category II Cat I Cat II Wetland Rating Form -western Washington 20 version 2 Updated with new WDFW definitions Oct 2008 August 2004 North Ridgeview Estates PlatHearing Examiner Packet Page 389 of 422 Wetland name or number SC 6.0 Interdunal Wetlands (see p. 93) Is the wetland unit west of the 1889 line (also called the Western Boundary of Upland Ownership or WBUO)? YES - go to SC 6.1 NO _&crfan interdunal wetland for rating If you answer yes you will still need to rate the wetland based on its functions. In practical terms that means the following geographic areas: • Long Beach Peninsula- lands west of SR. 103 • Grayland-Westport- lands west of SR105 • Ocean Shores-Copalis- lands west of SR 115 and SR 109 SC 6.1 Is the wetland one acre or larger, or is it in a mosaic of wetlands that is once acre or larger? YES = Category H NO-go to SC 6.2 SC 6.2 Is the unit between 0.1 and 1 acre, or is it in a mosaic of wetlands that i between 0.1 and 1 acre? YES = Category HI Wetland Rating Form-western Washington 21 version 2 Updated with new WDFW definitions Oct 2008 August 2004 North Ridgeview Estates PlatHearing Examiner Packet Page 390 of 422 Wetland name or number 3 WETLAND RATING FORM- WESTERN WASHINGTON "Version 2 - Updated July 2006 to increase accuracy and reproducibility among users Updated Oct 2008 with the new WDFW definitions for priority habitats Name of wetland (if known): _ Rated by_ SEC: TWNSHP: RNGE: Date of site visit 5 ' U>'/& _ Trained by Ecology? Yes No Date of training_ Is S/T/R in Appendix D? Yes. , No Mapofwetland unit: Figure Estimated size SUMMARY OF RATING Category based on FUNCTIONS ni'ovided by wetland i n ni iv S Category I = Score >=70 Category IT = Score 51-69 Category HI = Score 30-50 Category IV = Score < 30 Score for Water Quality Functions Score for Hydrologic Functions Score for Habitat Functions TOTAL score for Functions Category based on SPECIAL CEIARACTERISTICS of wetland I II Does not Apply ' Final Category (choose the "highest" category from above) Summary of basic information about the wetland unit C ll II Kill Mlo if** h ^^tlandlli.Mi !• •SKftflhu Kaluitt Estuarine Depressional Natural Heritage Wetland Riverine Bog Lake-fringe Mature Forest Slope Old Growth Forest Flats Coastal Lagoon Freshwater Tidal Interdunal / None ofthe above Check if unit has multiple HGM classes present Wetland luting Form-western Washington 1 veision2 To be used with Ecology Pubhcation 04-06-025 August 2004 Wetland name or number Does the wetland unit being rated meet any ofthe criteria below? If you answer YES to any ofthe questions below you will need to protect the wetland aocording to the regulations regarding the special characteristics found in the wetland. m Hi SPl. Has the wetland unit been documented as a habitat for any Federally listed Tlvealened or Endangered animal or plant species (T/E species)? For the purposes of this rating system, "documented" means the wetland is on the appropriate state or federal database. SP2. Has the wetland unit been documented as habitat for any State listed Threatened or Endangered animal species? For the purposes of this rating system, "documented" means the wetland is on the appropriate state database. Note: Wetlands with State listed plant species are categorized as Category I Natural Heritage Wetlands (see p. 19 of data form). y SP3. Does the wetland unit contain individuals of Priority species listed by the WDFW for the state? SP4. Does the wetland unit have a local significance in addition to its functions'! For example, the wetland has been identified in the Shoreline Master Program, the Critical Areas Ordinance, or in a local management plan as having special significance. To complete the next part of the data sheet you will need to determine the Hvdroeeomorphic Class of the wetland beins rated. The hydrogeomorphic classification groups wetlands into those that function in similar ways. This simplifies the questions needed to answer how well the wetland functions. The Hydrogeomorphic Class of a wetland can be determined using the key below. See p. 24 for more detailed instructions on classifying wetlands. Wetland Rating Form-western Washington 2 version 2 Updated with new WDFW definitions Oct 2008 August 2004 North Ridgeview Estates PlatHearing Examiner Packet Page 391 of 422 Wetland name or number 3 Classification of Wetland Units in Western Washington If the hydrologiccriteria listed in each question do not apply to the entire unit being mted, you probably have a unitwith multiple HGM classes. In this case, identify ..which, hydrologic criteria In questions 1-7 apply, and go to Question 8, , 1. Are the water levels in the entire unit usually controlled by tides (i.e. except during floods)? CFlO— goto-2 YES - the wetland class is Tidal Fringe —iEfrySs, is the salinity of the water during periods of annual low flow below 0.5 ppt (parts per thousand)? YES - Freshwater Tidal Fringe NO - Saltwater Tidal Fringe (Estuarine) If your wetland can be classified as a Freshwater Tidal Fringe use the formsfor Riverine wetlands. If it is Saltwater Tidal Fringe it is rated as an Estuarine wetland. Wetlands that were called estuarine in the first and second editions ofthe rating system are called Salt Water Tidal Fringe in the Hydrogeomorphic Classification. Estuarine wetlands were categorized separately in the earlier editions, and this separation is being kept in this revision. Tomaintain consistency between editions, the term "Estuarine" wetland is kept. Please note, however, that the characteristics that define Category I and H estuarine wetlands have changed (see p. ). 2. The entire wetland unit is flat and precipitation is the only source (>90%) of water to it. Grouruhvater and surface water runoff are NOT sources of water to the unit. (^5^3D3 YES-The wetland class is Flats If your wetland can be classified as a "Flats" wetland, use the form for Depressional wetlands. 3. Does the entire wetland unit meet both ofthe following criteria? The vegetated part ofthe wetland is on the shores of a body of permanent open water (without any vegetation on the surface) at least 20 acres (8 ha) in size; ———Atleast 30% ofthe open water area is deeper than 6.6 ft (2 m)? ^O-go-tf? 4 YES - The wetland class is Lake-fringe (Lacustrine Fringe) 4. Does the entire wetland unit meet all ofthe following criteria? , yTpe'wetland is on a slope (slope can be very gradual), "•The water flows through the wetland in one direction (unidirectional) and usually comes from seeps. It may flow subsurface, as sheetflow, or in a swale without ^jlrstinct banks. The water leaves the wetland without being impounded? NOTE: Surface water does not pond in these type ofwetlands except occasionally in very small and shallow depressions or behind hummocks (depressions are usually <3ft diameter andjess-mand-fiisldeep)^ NO - go to 5 ^nvc-^prr........ A .,„.r?rBT^ Wetland Rating Form- western Washington 3 version 2 Updated with new WDFW definitions Oct 2008 August 2004 Wetland name or number" 5. Does the entire wetland unit meet all ofthe following criteria? The unit is in a valley, or stream channel, where it gets inundated by overbank flooding from that stream or river The overbank flooding occurs at least once every two years. NOTE: The riverine unit can contain depressions that are filled with water when the river is not flooding. NO - go to 6 YES - The wetland class is Riverine 6. Is the entire wetland unit in a topographic depression in which water ponds, or is saturated to the surface, at some time during the year. This means that any outlet, if present, is higher than the interior of the wetland NO - go to 7 YES - The wetland class is Depressional 7. Is the entire wetland unit located in a very flat area with no obvious depression and no overbank flooding. The unit does not pond surface water more than a few inches. The unit seems to be maintained by high groundwater in the area. The wetland may be ditched, but has no obvious natural outlet, NO - go to 8 YES - The wetland class is Depressional 8rYour wetland unitseems to bedifficult to classify and-probably-contains several different HGM-— clases. For example, seeps at the base of a slope may grade into a riverine floodplain, or a small stream within a depressional wetland has a zone of flooding along its sides. GO BACK AND IDENTIFY WHICH OF THE HYDROLOGIC REGIMES DESCRIBED IN QUESTIONS 1-7 APPLY TO DIFFERENT AREAS IN THE UNIT (make a rough sketch to help you decide). Use the following table to identify the appropriate class to use for the rating system if you have several HGM classes present within your wetland. NOTE: Use this table only if tire class that is recommended in the second column represents 10% or more ofthe total area ofthe wetland unit being rated. If the area ofthe class listed in column 2 is less than 10% ofthe unit, classify the wetland using the class that represents more than 90% ofthe total area. • Slope + Riverine Riverine Slope + Depressional Depressional Slope + Lake-fringe Lake-fringe Depressional + Riverine along stream within boundary Depressional Depressional + Lake-fringe Depressional Salt Water Tidal Fringe and any other class of freshwater wetland Treat as ESTUARINE under wetlands with special characteristics If you are unable still to determine which ofthe above criteria apply to your wetland, or if you have more than 2 HGM classes within a wetland boundary, classify the wetland as Depressional for the rating. Wetland Rating Form-western Washington 4 version 2 Updated with new WDFW definitions Oct 2008 August 2004 North Ridgeview Estates PlatHearing Examiner Packet Page 392 of 422 Wetland name or number 'S- ' #$ S S 1. Does the wetland unit have the potential to improve water quality? (see p. 64) S S 1.1 Characteristics of average slope of unit Slope isl% or less (al% slope has a 1 foot vertical drop in elevation for every 100 ft horizontal distance) points = 3 Slope is 1% - 2% points = 2 Slope is 2% - 5% points = 1 Slope is greater than 5% rSmtsj^O^i s S 1.2 The soil 2 inches below the surface (or duff layer) is clay or organic (useNRCS definitions) YES = 3 points ,^-"NO = 0 pointed d s S 1.3 Characteristics of the vegetation in the wetland^at-rrajrseaTments and pollutants'. Choose the points appropriate for the description that best fits the vegetation in the wetland Dense vegetation means you have trouble seeing the soil surface (>75% cover), and uncut means not grazed or mowed andplants^are^higher'thsn^fnches. Dense, uncut, herbaceous vegetation > 90% ofthe wetland area ( points=^ Dense, uncut, herbaceous vegetation > 1/2 of area pomfs = 3 Dense, woody, vegetation > VS of area points = 2 Dense, uncut, herbaceous vegetation > 1/4 of area points = 1 Does not meet any ofthe criteria above for vegetation points = 0 Aerial photo or map with vegetation polygons Figure ^_ s Total for S1 Add the points in the boxes above -----s S 2. Does the wetland unit have the opportunity to improve water quality? Answer YES if you know or believe there are pollutants in groundwater or surface water coming into the wetland that would otherwise reduce water quality in streams, lakes or groundwater downgradlent from the wetland. Note which ofthe following conditions provide the sources ofpollutants. A unit may have pollutants coming from several sources, but any single source would qualify as opportunity. (see p. 67) — Grazing in the wetland or within 150ft — Untreated stormwater discharges to wetland — Tilled fields, logging, or orchards within 150 feet of wetland — Residential, urban areas, or golf courses are within 150 ft upslope of wetland — Other ____ -». YES multiplier is 2 multiplierjsj~^> multiplier ( s TOTAL - Water Quality Functions Multiply the score from SI by S2 Addscore to table on p. 1 c Comments Wetland Rating Form- western Washington 11 version 2 Updated with new WDFW definitions Oct 2008 August 2004 Wetland name or number s ' _ .. *t! i : :fe„„ yt, rv rV^Cn to f *Y; r • . • ... S 3. Does the wetland unit have the potential to reduce flooding and stream erosion? (see p. 68) s S 3.1 Characteristics of vegetation that reduce the velocity of surface flows during storms. Choose the points appropriate for the description that best fit conditions In the wetland (stems of plants should be thick enough (usually > l/8in), or dense enough, to remain erect during surface, flows) Dense, uncut, rigid vegetation covers > 90% of the area of the wetland. <5oints_2_6-i> Dense, uncut, rigid vegetation > 1/2 area of wetland points = 3 Dense, uncut, rigid vegetation > 1/4 area points = 1 More than 1/4 of area is grazed, mowed, tilled or vegetation is not rigid points = 0 s S 3.2 Characteristics of slope wetland that holds back small amounts of flood flows: The slope wetland has small surface depressions that can retain water over at least 10% of its area. YES points = 2 NO pt5infs = 0> <=» s Add the points in the boxes above s S 4. Does the wetland have the opportunity to reduce flooding and erosion? Is the wetland in a landscape position where the reduction in water velocity it provides helps protect downstream property and aquatic resources from flooding or excessive and/orergsive flows? Note which ofthe following conditions apply. —'Wetland has surface runoff that drains to ariver or stream that has flooding problems — Other (Answer NO if the major source of water is controlled by a reservoir (e.g. wetland Is a seep that is on thedownsjieam side of a dam) YES .multipIieriJCP3*' NO multiplier is 1 (seep, 70) multiplier s TOTAL - Hydrologic Functions Multiply the score from S 3 by S 4 Addscore to table on p. 1 IT-Comments Wetland Rating Form - western Washington 12 version 2 Updated with new WDFW definitions Oct 2008 August 2004 North Ridgeview Estates PlatHearing Examiner Packet Page 393 of 422 Wetland name or number H1. Does the wetland unit have the potential to provide habitat for many species? H 1.1 Vegetation structure (see D. 72) Check the types of vegetation classes present (as defined by Cowardin)-Size threshold for each class is 'A acrpor more than 10% ofthe area if unit is smaller than 2.5 acres. Aquatic bed •Emergent plants .Scrub/shrub (areas where shrubs have >30% cover) Forested (areas where trees have >30% cover) If the unit has a forested class check if: The forested class has 3 out of 5 strata (canopy, sub-canopy, shrubs, herbaceous, moss/ground-cover) that each cover 20% within the forested polygon Add the number ofvegetation structures that qualify. If you have: 4 structures or more points = 4 Map of Cowardinvegetation classes 3 structures points = 2 2 structures points = 1 1 structure points =Tr»? Figure. 6 -H 1.2. Hvdrooeriods (see v. 73) Check the types of water regimes (Itydroperiods) present within the wetland The water regime has to cover more than 10% of the wetland or Vt acre to count, (see text for descriptions of hydroperiods) Permanently flooded or inundated 4 or more types present points = 3 Seasonally flooded or inundated 3 types present points = 2 Occasionally flooded or inundated 2 types present point;= 1 ^"Saturated only 1 type present polSts^oV Permanently flowing stream or river in, or adjacent to, the wetland Seasonally flowing stream in, or adjacent to, the wetland Lake-fringe wetland = 2 points Freshwater tidal wetland" 2 points Map of hydroperiods Figure & H 1.3. Richness of Plant Species (seen. 75) Count the number of plant species in the wetland that cover at least 10 ft2, (different patches of the same species can be combined to meet the size threshold) You do not have to name the species. Do not Include Eurasian Milfoil, reed canarygrass, purple loosestrife, Canadian Thistle If you counted: > 19 species points = 2 List species below if you want to: 5-19 species points = 1 < 5 species (points ^J? Total for page Wetland Rating Form - western Washington 13 August 2004 version 2 Updated with new WDFW definitions OcL 2008 Wetland name or number H 1.4. Bitersoersion of habitats (see p. 76) Decide from the diagrams below whether interspersion between Cowardin vegetation classes (described in H 1.1), or the classes and unvegetated areas (can include open water or mudflats) is high, medium, low, ornone. None = 0 poG^si\w = 1 point Moderate = 2points ^\' [riparian braided channels] =!3ure _ High - 3 points - - _ NOTE: If you have four or more classes or three vegetation classes and open water the rating is always "high". Use map of Cowardin vegetation classes <£> H 1.5. Special Habitat Features: (seen. 77) Check the habitatfeatures that are present in the wetland The number ofchecks is the number of points you put into the next column. Large, downed, woody debris within the wetland (>4in. diameter and 6 ft long). Standing snags (diameter at the bottom > 4 inches) in the wetland Undercut banks are present for at least 6.6 ft (2m) and/or overhanging vegetation extends at least 3.3 ft (lm) over a stream (or ditch) in, or contiguous with the unit, for at least 33 ft (10m) Stable steep banks of fine material that might be used by beaver or muskrat for denning (>30degree slope) OR signs of recent beaver activity are present (cut shrubs or trees that haw not yet turned grey/brown) . At least VA acre of thin-stemmed persistent vegetation or woody branches are present in areas that are permanently or seasonally inundated (structures for egg-laying by amphibians) Invasive plants cover less than 25% ofthe wetland area in each stratum of plants NOTE: Tile 20% stated In early printings of the manual on page 78 is an error. a H1, TOTAL Score - potential for providing habitat Add the scores from Hl.l, H1.2, H1.3, H1.4, H1.5 a> J Comments Wetland Rating Form- western Washington 14 version 2 Updated with new WDFW definitions Oct 2008 August 2004 North Ridgeview Estates PlatHearing Examiner Packet Page 394 of 422 Wetland name or number H 2. Does the wetland unit have the opportunity to provide habitat for many species? H 2.1 Buffers (seep. SO) Choose the description that best represents condition of buffer ofwetland unit. The highest scoring criterion that applies to the wetland is to be used in the rating. See text for definition of "undisturbed " — 100 m (330ft) of relatively undisturbed vegetated areas, rocky areas, or open water >95% of circumference. No structures are within the undisturbed part of buffer, (relatively undisturbed also means no-grazing, no landscaping, no daily human use) Points = 5 — 100 m (330 ft) of relatively undisturbed vegetated areas, rocky areas, or open water > 50% circumference. Points = 4 — 50 m (170ft) of relatively undisturbed vegetated areas, rocky areas, or open water >95% circumference. Points = 4 •—• 100 m (330ft) of relatively undisturbed vegetated areas, rocky areas, or open water > 25% circumference,. Points = 3 — 50 m (170ft) of relatively undisturbed vegetated areas, rocky areas, or open water for > 50% circumference. Points - 3 If buffer does not meet any of the criteria above — No paved areas (except paved trails) or buildings within 25 m (80ft) of wetland>-95%-^ circumferenceTTighf to moderate grazing, of lawns are OK. /Points^^' •— No paved areas or buildings within 50m of wetland for >50% circumference.^ Light to moderate grazing, or lawns are OK. Points = 2 — Heavy grazing in buffer. Points = 1 , — Vegetated buffers are <2m wide (6.6ft) for more than 95% of the circumference (e.g. tilled fields, paving, basalt bedrock extend to edge of wetland Points = 0. — Buffer does not meet any of the criteria above. Points = 1 Aerial photo showing buffers Figure -z. H 2.2 Corridors and Connections (see p. SI) H 2.2.1 Is the wetland part of a relatively undisturbed and unbroken vegetated corridor (either riparian or upland) that is at least 150 ft wide, has at least 30% cover of shrubs, forest or native undisturbed prairie, that connects to estuaries, other wetlands or undisturbed uplands that are at least 250 acres in size? (dams in riparian corridors, heavily used gravel roads, paved roads, are considered breaks in the corridor). YES = 4 points (go to H 2.3) NO = go to H 2.2.2 H 2.2.2 Is the wetland part of a relatively undisturbed and unbroken vegetated corridor (either riparian or upland) that is at least 50ft wide, has at least 30% cover of shrubs or forest, and connects to estuaries, other wetlands or undisturbed uplands that are at least 25 acres in size? OR a Lake-fringe wetland, if it does not have an undisturbed corridor as in the question above? YES =2 points (go to H 2.3) NO = H 2.2.3 H 2.2.3 Is the wetland: wjthin 5 mi (8km) of a brackish or salt water estuary OR ^-whin 3 mi of a large field or pasture (>40 acres) OR withh^ml-ofgdde greater than 20 acres? (YES = 1 poh> NO = 0 points Total for page_ Wetland Rating Form- western Washington 15 version 2 Updated with new WDFW definitions Oct 2008 August 2004 Wetland name or number H 2.3 Near or adiacentto other priority habitats listed bv WDFW (see new and complete descriptions oj'WDFWpriorit)' /latitats, andtlie counties inwhich tltey can be found, in the PBS report http://mUto.wa. eov/hab/phstist, htm) Which ofthe following priority habitats are within 330ft (100m) ofthe wetland unit? NOTE: the connections do not have to be relatively undisturbed. Aspen Stands: Pure or mixed stands of aspen greaterthan0.4ha(l acre). Biodiversity Areas and Corridors: Areas of habitat that are relatively important to various species of native fish and wildlife (full descriptions In WDFW PBS report p. 152). Herbaceous Balds: Variable size patches of grass and forbs on shallow soils over bedrock. Old-growth/Mature forests: (Old-growth west of Cascade cresf) Stands of at least 2 tree species, forming a multi-layered canopy with occasional small openings; with at least 20 trees/Ira (8 trees/acre) > 81 cm (32 in) dbh or > 200 years of age. (Mature forests! Stands with average diameters exceeding 53 cm (21 in) dbh; crovwi cover may be less that 100%; crown cover may be less that 100%; decay, decadence, numbers of snags, and quantity of large downed material is generally less than that found in old-growth; 80 - 200 years old west ofthe Cascade crest. .Oregon white Oak: Woodlands Stands of pure oak or oak/conifer associations where canopy coverage of the oak component is important (full descriptions in WDFW PBS report p. 158). Riparian: The area adjacent to aquatic systems with flowing water that contains elements of both aquatic andlerresMafecosystems^Mch'm^ Westside Prairies: Herbaceous, non-forested plant communities that can either take the form of a dry prairie or a wet prairie (full descriptions in WDFW PBS report p. 161). Instream: The combination of physical, biological, and chemical processes and conditions that interact to provide functional life history requirements for instream fish and wildlife resources. Nearshore: Relatively undisturbed nearshore habitats. These include Coastal Nearshore, Open Coast Nearshore, and Puget Sound Nearshore. (full descriptions of habitats and the definition ofrelatively undisturbed are in WDFW''report: pp. 167-169 and glossary in AppendixA). Cayes: A naturally occurring cavity, recess, void, or system of interconnected passages under the earth in soils, rock, ice, or other geological formations and is large enough to contain a human. Cliffs: Greater than 7.6 m (25 ft) high and occurring below 5000 ft. Talus: Homogenous areas of rock rubble ranging in average size 0.15 - 2,0 m (0.5 - 6.5 ft), composed of basalt, andesite, and/or sedimentary rock, including riprap slides and mine tailings. Maybe associated with cliffs. Snags and Logs: Trees are considered snags if they are dead or dying and exhibit sufficient decay characteristics to enable cavity excavation/use by wildlife. Priority snags have a diameter at breast height of > 51 cm (20 in) in western Washington and are > 2 m (6.5 ft) in height. Priority logs are > 30 cm (12 in) in diameter at the largest end, and > 6 m (20 ft) long. If wetland has 3 or more priority habitats = 4 points If wetland has 1 priority habitats = 3 points If wetland has 1 priority habitat™ 1 point No habitats = 0 points Note: All vegetated wetlands are by definition a priority habitat but are not included in this list. Nearby wetlands are addressed In question B 2.4) __ Wetland Rating Form -western Washington 16 version 2 Updated with new WDFW definitions Oct 2008 August2004 North Ridgeview Estates PlatHearing Examiner Packet Page 395 of 422 Wetland name or number 3 H 2.4 Wetland Landscape (choose the one description of the landscape around the wetland that best fits) (seep. 84) There are at least 3 other wetlands within 14 mile, and the connections between them are relatively undisturbed (light grazing between wetlands OK, as is lake shore with some boating, but connections should NOT be bisected by paved roads, fill, fields, or other development. points = 5 The wetland is Lake-fringe on a lake with little disturbance and there are 3 other lake-fringe wetl ands vvithin '/a mile points = 5 There are at least 3 other wetlands within 'A mile, BUT the connections between them are disturbed pojntsj^J The wetland is Lake-fringe on a lake with disturbance and there are 3 other lake-fringe wetland within lA mile points = 3 There is at least 1 wetland wiurin Vi mile. points = 2 There are no wetlands within lA mile. points = 0 3 H2. TOTAL Score - opportunity for providing habitat Add the scores from H2.1.H2.2, H2.3, H2.4 , 1 0= 1 TOTAL forH 1 from page 14 o Total Score for Habitat Functions - add the points for H 1, H 2 and record the result on P.l 6 Wetland Rating Form - western Washington 17 version 2 "Updated with new WDFW definitions Oct 2008 August 2004 Wetland name or number CATEGORIZATION BASED ON SPECIAL CHARACTERISTICS Please determine if the wetland meets the attributes described below and circle the appropriate anmers and Category. Wetland Type Checkoff any criteria that apply to me wellandCirciedieCategorywheti the appropriate criteria are met. . Category SC 1.0 Estuarine wetlands (see p. 86) Does the wetland unit meet the following criteria for Estuarine wetlands? — The dominant water regime is tidal, •— Vegetated, and y —• With a salinity greater than 0.5 ppt. / YES = Goto SC 1.1 NO / SC 1.1 Is the wetland unit within a National Wildlife Refuge, National Park, National Estuary Reserve, Natural Area Preserve, State Park or Educational, -Environmental,-orScientifio-Reserve designated-under WAC 332-30-151? YES = Category I NO go to SC 1.2 Cat I SC 1.2 Is the wetland unit at least 1 acre in size and meets at least two ofthe following three conditions? YES = Category I NO = Category II — The wetland is relatively undisturbed (has no diking, ditching, filling, cultivation, grazing, and has less than 10% cover of non-native plant species. If the non-native Spartina spp. are the only species that cover more than 10% ofthe wetland, then the wetland should be given a dual rating tJ/S). The area of Spartina would be rated a Category II while the relatively undisturbed upper marsh with native species would be a Category I. Do not, however, exclude the area of Spartina in determining the size threshold of 1 acre. •—• At least Yt ofthe landward edge ofthe wetland has a 100 ft buffer of shrub, forest, or un-grazed or un-mowed grassland. — The wetland has at least 2 ofthe following features: tidal channels, depressions with open water, or contiguous freshwater wetlands. Cat I Cat II Dual rating I/II Wetland Rating Form- western Washington 18 version 2 Updated with new WDFW definitions Oct 2008 August 2004 North Ridgeview Estates PlatHearing Examiner Packet Page 396 of 422 Wetland name or number SC2.0 Natural Heritage Wetlands (seep. 87) Natural Heritage wetlands have been identified by the Washington Natural Heritage Program/DNR as either high quality undisturbed wetlands or wetlands that support state Threatened, Endangered, or Sensitive plant species. SC 2.1 Is the wetland unit being rated in a Section/Township/Range that contains a Natural Heritage wetland? (this question is used to screen out most-sites beforeyou need to contact WNHP/DNR) S/T/R information from Appendix D or accessed from WNHP/DNR web site YES - contact WNHP/DNR (see p. 79) and go to SC 2.2 NO ^ SC 2.2 Has DNR identified the wetland as a high quality undisturbed wetland or as or as a site with state threatened or endangered plant species? YES = Category I NO not a Heritage Wetland Cat I SC 3.0 Bogs (seep. 87) Does the wetland unit (or any part of the unit) meet both the criteria for soils and vegetation in-bogs? Use the key-below to identify if the wetland is a bog. If you answer yes you will still need to rate the wetland based on its functions. 1. Does the unit have organic soil horizons (i.e. layers of organic soil), either peats or mucks, that compose 16 inches or more ofthe first 32 inches ofthe soil profile? (See Appendix B for,aiieldJceyto identify organic soils)? Yes -go to Q. 3 S*No - go toC>2^ 2. Does the unit have organic sons, eifner peats or mucks that are less than 16 inches deep over bedrock, or an impermeable hardpan such as clay or volcanic ash, or that are floating on a lakera-portd? "==~c°*"""— Yes - go to Q. 3 No - Is not a bog for purpose of rating> 3. Does the unit have more than 70% coverof-mosses at gtound-levelTAND other plants, if present, consist ofthe "bog" species listed in Table 3 as a significant component ofthe vegetation (more than 30% ofthe total shrub and herbaceous cover consists of species in Table 3)? Yes-Is a bog for purpose of rating No- go to Q. 4 NOTE: If you are uncertain about the extent of mosses in the understory you may substitute that criterion by measuring the pH ofthe water that seeps into a hole dug at least 16" deep. If the pH is less than 5.0 and the "bog" plant species in Table 3 are present, the wetland is a bog. 1. Is the unit forested (> 30% cover) with sifka spruce, subalpine fir, western red cedar, western hemlock, lodgepole pine, quaking aspen, Englemann's spruce, or western white pine, WITH any ofthe species (or combination of species) on the bog species plant list in Table 3 as a significant component ofthe ground cover (> 30% coverage of the total shrub/herbaceous cover)? 2. YES = Category I No Is not a bog for purpose of rating Cat! Wetland Rating Form - western Washington 19 version 2 Updated with new WDFW definitions Oct 2008 August 2004 Wetland name or number SC 4.0 Forested Wetlands (see p. 90) Does the wetland unit have at least 1 acre of forest that meet one of these criteria for the Department of Fish and Wildlife's forests as priority habitats? If you answer yes you will still need to rate the wetland based on its functions. •— Old-growth forests: (west of Cascade crest) Stands of at least two tree species, forming a multi-layered canopy with occasional small openings; with at least 8 trees/acre (20 trees/hectare) that are at least 200 years of age OR have a diameter at breast height (dbh) of 32 inches (81 cm) or more. NOTE: The criterion for dbh is based on measurements for upland forests. Two-hundred year old trees in wetlands will often have a smaller dbh because their growth rates are often slower. The DFW criterion is and "OR" so old-growth forests do not necessarily have to have trees of this diameter. — Mature forests: (west ofthe Cascade Crest) Stands where the largest trees are 80-200 years old OR have average diameters (dbh) exceeding 21 inches (53cm); crown cover may be less that 100%; decay, decadence, numbers of snags, and quantity of large downed material is generally less than that found in old-growth. YES = Category I NO -/not a forested wetland with special characteristics Cat I SC 5.0 Wetlands in Coastal Lagoons (seep. 91) Does the wetland meet all ofthe following criteria of a wetland in a coastal lagoon? — The wetland lies in a depression adjacent to marine waters that is wholly or partially separated from marine waters by sandbanks, gravel banks, shingle, or, less frequently, rocks — The lagoon in which the wetland is located contains surface water that is saline or brackish (> 0.5 ppt) during most ofjhe year in at least a portion ofthe lagoon (needs to be measured near^he bottom) YES = Go to SC 5.1 NO •/not a wetland in a coastal lagoon SC 5.1 Does the wetland meets all ofthe following three conditions? — The wetland is relatively undisturbed (has no diking, ditching, filling, cultivation, grazing), and has less than 20% cover of invasive plant species (see list of invasive species on p. 74). •— At least 'A of tire landward edge ofthe wetland has a 100 ft buffer of shrub, forest, or un-grazed or un-mowed grassland. —• The wetland is larger than 1/10 acre (4350 square feet) YES = Category I NO = Category II Cat I Cat. II Wetland Rating Form -western Washington 20 version 2 Updated with new WDFW definitions Oct 2008 August 2004 North Ridgeview Estates PlatHearing Examiner Packet Page 397 of 422 Wetland name or number SC 6.0 Interdunal Wetlands (seep. 93) Is the wetland unit west ofthe 1889 line (also called the Western Boundary of Upland Ownership or WBUO)? YES - go to SC 6.1 NO ^/dot an interdunal wetland for rating If you answer yes you will still need to rate the wetland hosed on its functions. In practical terms that means the following geographic areas: • Long Beach Peninsula- lands west of SR 103 • Grayland-Westport- lands west of SR 105 • Ocean Shores-Copalis- lands west of SR 115 and SR 109 SC 6.1 Is the wetland one acre or larger, or is it in a mosaic of wetlands that is once acre or larger? YES = Category II NO — go to SC 6.2 SC 6.2 Is the unit between 0.1 and 1 acre, or is it in a mosaic of wetlands that is between 0.1 and 1 acre? YES = Category HI •miwiin»iwr. n i» "h iiirtai||Wlf^lV^WByfTifl| •jLh/fi'<TMEJ3Jfoy'vp,!-iiwo._;i,ffini?T<,~." :.tdk> .iZ.-\-..'--lW!r!i!t3lmtm Wetland Rating Form- western Washington 21 version 2 Updated with new WDFW definitions Oct 2008 August 2004 North Ridgeview Estates PlatHearing Examiner Packet Page 398 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 399 of 422 -This page left intentionally blank- North Ridgeview Estates Plat Hearing Examiner Packet Page 400 of 422 EXHIBIT 12 PRELIMINARY WETLAND AND BUFFER MITIGATION PLANS, PREPARED BY SEWALL WETLAND CONSULTANTS, 5/4/2017 North Ridgeview Estates Plat Hearing Examiner Packet Page 401 of 422 -This page left intentionally blank- North Ridgeview Estates Plat Hearing Examiner Packet Page 402 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 403 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 404 of 422 EXHIBIT 13 PLAT MODIFICATION REQUEST WRITTEN STATEMENT North Ridgeview Estates Plat Hearing Examiner Packet Page 405 of 422 -This page left intentionally blank- North Ridgeview Estates Plat Hearing Examiner Packet Page 406 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 407 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 408 of 422 EXHIBIT 14 VARIANCE REQUEST WRITTEN STATEMENT North Ridgeview Estates Plat Hearing Examiner Packet Page 409 of 422 -This page left intentionally blank- North Ridgeview Estates Plat Hearing Examiner Packet Page 410 of 422 January 10, 2017 Project name: North Ridgeview Preliminary Plat AKA – Plemmons and/or Ridgeview Estates Variance application: We are formally requesting that the front, side and backyard setbacks be adjusted from the R1 zone setbacks to the R5 zone setbacks for the North Ridgeview Preliminary Plat, primarily based on the fact that this site is located within an “Urban Separator” overlay which requires standards that dramatically impact the lot size and the house arrangement to be more in line with the R5 lot size. Current Setbacks: R1 Zone Table 18.07.030 Residential Development Standards Residence front yard 35’ Interior side yard 10’ Rear setback 35’ Side street setback 20’ Minimum lot size 35,000 Minimum lot size (overlay) 8,000 Proposed Setbacks: R5 Zone Table 18.07.030 Residential Development Standards Residence front yard 10’ Interior side yard 5’ Rear setback 20’ Side street setback 10’ Minimum average lot area per dwelling unit 8,000 Minimum lot area per dwelling unit 6,000 City Variance Criteria (and responses): 1.That there are unique physical conditions including narrowness or shallowness of lot size or shape, or exceptional topographical or other physical conditions peculiar to and inherent in the particular lot; and that, as a result of such unique physical conditions, practical difficulties or unnecessary hardships arise in complying with provisions of the zoning code RESPONSE: Due to the constraints of the 1. Site topography, 2. 50% open space requirement required by the Urban Separator Overlay, 3. Onsite wetlands, 4. Less than idea soils which will require a larger drainage facility, 5. Drainage facility location, 6. Required North Ridgeview Estates Plat Hearing Examiner Packet Page 411 of 422 collector road location onsite that will someday in the future connect 124th and 132nd, and 7. Easement locations and restrictions (see attached map of easements) on this property the layout of the site cannot easily be adjusted to accommodate the setbacks as proposed by the R1 zoning code. The proposed setbacks would create very narrow building pads that do not accommodate a marketable finished product. All of these site specific constraints combine to create lots along the proposed (city required) collector road that will be on a very steep existing slope down to the back of the lots. This results in excessive fill to construct a home that will require daylight basements and will require the houses to be placed as close as possible to the street (20’ vs. 35’) to minimize the house being placed up in the air, even with a basement. The access to the site has been determined by the city to be located as proposed based on the available sight distance, grades and intersection spacing, therefore there is no reasonable alternative to a different road design or location. Also, and most importantly the Urban Separator overlay, which the city inherited from the County upon annexation, requires that 50% of the site must remain in open space and allows lots as small as 8,000 square feet. This minimum average lot area per dwelling unit in the R5 zone is 8,000 square feet, which is the same as in the R1 zone within the Urban Separator zoning regulations, therefore, the R5 setbacks should apply to the resultant smaller lots. Based on the reasons above, unnecessary hardships would occur if the existing R1 standards would apply. 2. That because of such physical conditions, the development of the lot in strict conformity with the zoning code will not allow a reasonable and harmonious use of such lot RESPONSE: Topography: The site has several physical conditions that interfere with the design process of our project. The site is at its lowest elevations along northwest and northeast corners and rises to the south. The highest elevations are located in the southern portions of the property. The steepest slopes on site are in the 20% range. The site is planned to be mass graded at the time of construction. Maximum flexibility of the house placement, such as the R5 setbacks, within the proposed lots is required to reasonably develop the land. Wetlands: The site also has several wetlands which cannot be encroached. The wetlands area as well as their buffers are to be left as-is. Please see attached Wetland Report created by Sewall Consulting. These wetlands further constrain potential road design and lot locations. North Ridgeview Estates Plat Hearing Examiner Packet Page 412 of 422 Roads: A “collector” street is being required by the City of Auburn will allow for a future connection between 124th Ave SE and 132nd Ave SE (eventually). We will provide this road connection through our property and it will stub out for others to connect it during future development of the neighboring sites to the east. Due to the slopes of the site there is only one location on site that this road can physically be built. These factors limit our lot locations, layout and building pads within the lots and contribute to the R1 setbacks not allowing a reasonable and harmonious use of the property. Soils: A report prepared by Earth Solutions Northwest has identified the soils onsite to be glacial till and outwash deposits as a result of preliminary soils testing. Please see attached soils report created by ESNW on July 27, 2016. Due to these soils conditions, maximum flexibility of the home placement on each proposed lot is needed to allow reasonable use of the property. Lot size: For example on a 80’ wide lot with a depth of 100’ under the R1 zone the building pad would be reduced to 60’ wide and 30’ deep. If that same lot was in the R5 zone the building pad would be 70’ wide by 70’ deep which is a buildable pad size for a home that is marketable in today’s market. For proposed lots 1-11 the elevation fall in the backyard will be such that the homes will need to be as close to the front property line as reasonably possible (10-20’) in order to provide the home with any sort of a usable backyard (while still requiring a daylight basement). By requiring the clustering of lots per the Urban Separator Overlay, we believe this results in a neighborhood feeling with separation being accomplished in the open space. The setbacks of the R5 zone are more conducive to this type of a neighborhood, with the reduced lot sizes. Since the Urban Separator allows lots of 8,000 square feet, due to the extensive open space requirements, the lot layout and design will result in lots that match the size, scale and arrangement of a R5 neighborhood. 3. That the variance, if granted, will not alter the character of the neighborhood, or be detrimental to surrounding properties in which the lot is located RESPONSE: If the variance is granted, we believe that the character of this neighborhood will only be benefited by lots with smaller setbacks. Smaller front yard and side yard setbacks will allow for a buildable pad that will provide a more marketable product with a house footprint at a size that is standard in the market today. Today’s market is geared North Ridgeview Estates Plat Hearing Examiner Packet Page 413 of 422 towards a product that is at least 40-50’ wide and 50-70’ deep and can provide a 2-3 car garage. Setbacks as defined by the R-1 zone create very narrow lots that will not accommodate such an industry standard product. Surrounding Properties: The neighborhood is surrounded to the north by a wetland as well as other single family homes on larger estate-sized lots. The property is surrounded to the east by single family homes on large lots and a vacant piece of land which is slated for a future elementary school. To the south of the property are more single family homes and Auburn Mountainview High School. To the west of the property is a City of Kent water tower, a church and more single family homes. Our proposed development will fit the character of the surrounding areas as much as reasonably possible given that we are required to provide nearly 15 acres of open space. This 50% open space will act as a substantial buffer from surrounding properties therefore, the requested reduced setbacks will not be an impact upon the surrounding properties. 4.That the special circumstances and conditions associated with the variance are not a result of the actions of the applicant or previous owners RESPONSE: The variance request is partially based on the existing, and apparently natural, site conditions (i.e. slopes, wetlands and soils), but the variance request is predominantly based on the restrictions of the Urban Separator Overlay on the use of the property. The overlay requires that 50% of the site be placed in open space and that the minimum lot size can be 8,000 square feet as a result. The R1 setbacks will not allow for reasonable use of the resultant lots and we believe that the R1 setback standards were not considered or updated when the city applied the Urban Separator Overlay to this site. As a result the R1 setbacks do not match up with the Urban Separator Overlay restrictions in the city code. The proposed lots are of the configuration and size that best matches the setbacks and intent for the R5 zoning codes which is what we are asking for. 5.Literal interpretation of the provisions within the zoning code would deprive the applicant of rights commonly enjoyed by other properties in the same zoning district RESPONSE: We believe that due to the Urban Separator Overlay regulations this neighborhood will have the feel and finished look of a similar neighborhood within the R5 zoning based on lot size, finished product and layout. The only major difference will be that our finished product will provide 15 acres of open space which similar neighborhoods have not been required to provide since this is the first application of a residential plat in the R1 zone with the Urban Separator Overlay in the City of Auburn. This property cannot enjoy the rights that other R1 properties enjoy due to the 50% open space requirement of the Urban Separator Overlay. North Ridgeview Estates Plat Hearing Examiner Packet Page 414 of 422 6.The approval of the variance will be consistent with the purpose of the zoning code and the zoning district in which the property is located RESPONSE: We believe that the Urban Separator Overlay regulations and requirements do not match the setback requirements in the R1, therefore when a site such as this is regulated by both, one of these city requirements must give to the other. It appears that the City did not intend for their codes to conflict but since there has not been any residential plats submitted for City review within the R1 zoned land that also has the Urban Separator Overlay, this code conflict has not come up until now. We believe that the intent of the Urban Separator overlay will remain intact with our requested revisions to the setbacks. 7.The authorization of such variance will not adversely affect the Comprehensive Plan RESPONSE: We do believe the Comprehensive Plan will not be adversely affected by the reduction of setbacks on the lots. Our variance simply adjusts the setbacks of these lots to provide a building pad that allows for a reasonable use for the lots that are required to be significantly reduced by the regulation within the Urban Separator Overlay. We are asking for an adjustment to fit the size and characteristics of the required smaller lots versus the R1 zone requirements which typically has a lot size of at least 35,000 square feet. The lots we are proposing are as small as 10,040 square feet (but can also be as small as 8,000 square feet). Our requested variance scales the setbacks to meet the size of the proposed lots that result from the Urban Overlay requirements. North Ridgeview Estates Plat Hearing Examiner Packet Page 415 of 422 -This page left intentionally blank- North Ridgeview Estates Plat Hearing Examiner Packet Page 416 of 422 EXHIBIT 15 DEVIATION REQUESTS – CITY ENGINEER RECOMMENDATION, 1/8/2018 North Ridgeview Estates Plat Hearing Examiner Packet Page 417 of 422 -This page left intentionally blank- North Ridgeview Estates Plat Hearing Examiner Packet Page 418 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 419 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 420 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 421 of 422 North Ridgeview Estates Plat Hearing Examiner Packet Page 422 of 422