HomeMy WebLinkAbout04-17-2013 HEARING EXAMINER AGENDA PACKET
HEARING EXAMINER
April 17, 2013
5:30 p.m.
City Council Chambers
25 West Main Street
I. Case No: PLT08-0002 – River Rock 4 Preliminary Plat
Applicant: Jason Cole, JD 45 LLC, 6709 166th Avenue East, Sumner, WA 98390
Request: Preliminary plat for a 14-lot single family residential subdivision on
approximately 6.03 acres. Lots will range from 9,456 square feet
to 28,519 square feet in area. Primary vehicle access will be from
Oravetz Road SE and a proposed extension of approximately 360
feet of new public street and three private access tracts. The
proposal also includes construction of utilities and infrastructure
including a storm drainage facility within a publicly dedicated tract
and a water system pressure reducing station and associated
maintenance access within an adjacent undeveloped right-of-way.
Project Location: The approximately 6.03 acre site is located on the south side of
the 4600 block of Oravetz Road SE, Auburn, WA 98002, within
the NW quarter of the NE quarter of Section 31, Township 21
North, Range 5 East, W.M. Parcel Number 3121059070.
Exhibit 1
Number of Pages 25
AGENDA BILL APPROVAL FORM
Agenda Subject Preliminary Plat of River Rock 4, PLT08-0002
Date: April 8, 2013
Department: Planning, and
Development Dept.
Attachments: Please refer to Exhibit
List at end
Budget Impact: N/A
Administrative Recommendation:
Hearing Examiner to conduct public hearing and approve the Preliminary Plat of River Rock 4, based
upon the Findings of Facts, Conclusions and Conditions as outlined.
APPLICANT: Jason Cole, JD 45 LLC
6709 166th Avenue East
Sumner ,WA 98390
AGENT: Hans Korve, Planner
Daley–Morrow-Poblete, Inc.
726 Auburn Way North
Auburn WA 98002
REQUEST: Approval of preliminary plat for a 14-lot residential subdivision known as
River Rock 4 on vacant approximately 6.03 acres.
LOCATION: The proposal is generally located on the south side of the 4600 block of
Oravetz RD SE, Auburn, WA 98002, within the NW quarter of the NE
quarter of Section 31, Township 21 North, Range 5 East, W.M. Parcel
Number: 3121059070
EXISTING ZONING: Vested to R1, Residential Zoning district standards (2008). Current
designation is R5, Residential Five Dwelling Units Per Acre.
EXISTING LAND USE Vacant
COMPREHENSIVE PLAN
DESIGNATION: Single Family Residential
SEPA STATUS: Mitigated Determination of Non-Significance (City File #SEP08-0007)
issued March 15, 2013. No comments received.
Reviewed by Council & Committees: Reviewed by Departments & Divisions:
Arts Commission COUNCIL COMMITTEES: Building M&O
Airport Finance Cemetery Mayor
Hearing Examiner Municipal Serv. Finance Parks
Human Services Planning & CD Fire Planning
Park Board Public Works Legal Police
Planning Comm. Other Public Works Human Resources
Action:
Committee Approval: Yes No
Council Approval: Yes No Call for Public Hearing ___/___/____
Referred to _________________________________ Until ____/___/____
Tabled ______________________________________ Until ___/___/____
Councilmember: Staff: Dixon
Meeting Date: April 17, 2013 Item Number:
Agenda Subject – PLT08-0002
River Rock 4 Preliminary Plat
Page 2 of 25
I. SEPA STATUS
Pursuant to the State Environmental Policy Act (SEPA) and City of Auburn Environmental
Regulations, as codified in Auburn City Code (ACC) Title 16, Environmental Review
Procedures, the SEPA Responsible Official reviewed this project and issued a Mitigated
Determination on Non-Significance on March 15, 2013.
II. FINDINGS OF FACT
A. Current and Planned Uses of the Site
The Comprehensive Plan designation, zoning classification and current land uses of the site
and surrounding properties are:
Comprehensive Plan
Designation
Zoning
Classification
Current Land Use
Site
Single Family Residential R5, Residential Five
Dwelling Units Per
Acre (Vested to
prior R1,
Residential).
Vacant
North Single Family Residential
and across Oravetz Rd
SE: Public & Quasi-Public
R5, Residential Five
Dwelling Units Per
Acre and across
Oravetz Rd SE: P1,
Public Use
Single family residential
and across Oravetz Rd
SE: high school ball fields
and public park
South Single Family Residential R5, Residential Five
Dwelling Units Per
Acre
Single family
residential
East Single Family Residential R5, Residential Five
Dwelling Units Per
Acre
Single family
residential and
vacant
West Across Oravetz Rd SE:
Public & Quasi-Public
Across Oravetz Rd
SE: P1, Public Use
Across Oravetz Rd SE,
high school ball fields and
public park
Agenda Subject – PLT08-0002
River Rock 4 Preliminary Plat
Page 3 of 25
Agenda Subject – PLT08-0002
River Rock 4 Preliminary Plat
Page 4 of 25
B. Project Information
1. Jason Cole of JD 45 LLC, Applicant, represented by Hans Korve of Daley–Morrow-Poblete
Inc. filed applications for a preliminary plat referred to as “River Rock 4.” The proposal
includes subdivision of an approximately 6.03 acre site into fourteen (14) lots and three
private utility/access tracts and one public storm drainage tract. The Applicant has not
identified any phasing of the plat thus, it would occur in a single phase.
2. The project has a varied and complicated history of applications to the City that is
summarized as follows:
In 2007 the city received a boundary line adjustment application titled: “River Rock 2”. (File
# BLA07-0005) to move the lot line between what was then parcels # 3121059048 and
#3021059357 and shift the boundary south. The boundary line was approved August 28,
2007 under recording #20070904900009.
In February 25 2008, the city received an environmental checklist application (pursuant to
the State Environmental Policy Act (SEPA)) and preliminary plat application for the
subdivision into 17 lots of 8.85 acres (Two parcels, Parcel # 3121059048 and
#3121059018). Because of complexities with the project, it went through a couple of city
reviews. City letters requesting revisions, clarifications and additional information were
sent on March 19, 2008 and September 10, 2008. However, the City deemed the
applications “complete“ for processing by letter as of July 16, 2008 but requested additional
information to make both SEPA and plat decisions. In 2009 the City replaced the R1,
Residential zoning district and development standards with the present R5, residential
zoning district and development standards. The project is vested to the standards of the
previous R1, Residential zoning district.
Subsequently, it was acknowledged by the Applicant that due to changes in economic
circumstances, the preliminary plat and SEPA applications were not as actively pursued.
In July 2009 a boundary line adjustment application was received for adjusting the
boundary between two parcels (File #BLA09-00002). This boundary line adjustment was
approved by the City in September 2009 (BLA09-0002, Recording # 20090908900003).
Subsequently, in January 2011 another boundary line adjustment application was applied
for involving some of the same original lots as the preliminary plat. The Boundary line
adjustment was subsequently approved by the City in April 2011 and recorded in May 2011
(BLA11-0001, Recording # 20110502900003).
Through the approval of the two lots line adjustments in the intervening period, the
boundaries of the parcels involved in the original preliminary plat application have changed.
The two lots resulting from the BLA’s were subsequently issued building permits and
developed with single family homes. As a result, the amount of property involved in the
preliminary plat application is reduced by the area of these two developed lots.
The City received a revised preliminary plat application and environmental checklist
application submitted on July 2011 and evaluated the changes to the project. Based on
subsequent City reviews, Deviations from City (Public Works) standards are required for
the project and were submitted on February 7, 2012 and the remainder of the preliminary
plat information submitted on February 15, 2012. Also as a result of revised location of the
water system pressure reducing station on the latest plans and its associated off-site
Agenda Subject – PLT08-0002
River Rock 4 Preliminary Plat
Page 5 of 25
access road, the Applicant provided reconnaissance-level wetland report information
received on December 5, 2012.
3. The subject site is vacant and forested and the proposal is for site preparation and
construction of a 14-lot single-family residential subdivision on approximately 6.03 acres.
4. The proposal also includes construction of related utilities and infrastructure.
5. The fourteen lots will be used for single family detached homes. The smallest lot size will
be 7,956 square feet. The density for fourteen single family lots on 6.03 acres is 2.32
dwelling units per acre under the former code definition of “Density” (ACC 18.04.300).
ACC 18.040.300 Density
“Density” means the total number of units within a specific area calculated by
dividing the total number of square feet of the area by the number of dwelling
units in the area.
6. The preliminary plat (Sheet 2 of 7) identifies the plat is proposed to include four tracts as
follows:
• Tract A – Private, A joint use driveway tract to the conveyed to the owners of
Assessor’s Parcel # 3121059018 and 33121059048 (Lots off-site to the east)
• Tract B – Private, And ingress and egress and utility Tract shall be conveyed to the
future owners of Lots 5, 6, 7, 8, 9, and 10 of the plat.
• Tract C – Private, A joint use driveway tract shall be conveyed to the future owners
of Lots 7 and 8 of the plat.
• Tract D – Public, A storm drainage tract, shall be conveyed to the City of Auburn for
ownership. (See proposed conditions of approval for shared maintenance
responsibility)
7. Primary access to the future lots will be from Oravetz RD SE by a proposed extension of
approximately 360 feet of new public street and three private access tracts. The original
plat road configuration submittal exceeded the city’s vested road grade standards for a new
public street. A subsequent revision of the plat, shifting the proposed road north and more
diagonal to the slope, submitted on September 21, 2012, reduced the grade to an amount
that can be authorized by deviations per the process of City of Auburn Engineering Design
Standards Manual, Section 1.03 with approval by the Hearing Examiner.
8. The proposed public street is to be developed generally consistent with the City’s “Local
Residential Street Standard” with twenty-eight (28) feet of road surface within a fifty- (50)
foot right-of-way.
9. The irregular 6.03 acre site measures approximately 698 feet north to south and varies
from 442 to 321 feet east to west. The site varies in elevation from 210 feet near the NE
corner to 110 feet near the southwest corner. The site is dominated by a northwesterly
facing hillside varying generally from 10% to 21% slopes. The site is forested with
scattered trees and mature understory vegetation. The forested area is bisected by a piped
drainage and shared driveway within an easement roughly aligned east-west accessing two
lots and developed houses that are off-site east of the plat.
10. The subject property and its ground surface elevation occur at the boundary of two
pressure zones of the city’s public water system. In order to adequately serve the
Agenda Subject – PLT08-0002
River Rock 4 Preliminary Plat
Page 6 of 25
proposed lots, the installation of a pressure reducing valve/station (PRV) is required on the
new main looping through the property from Kennedy AV SE to bring water system
pressure within acceptable limits. The looped water main and pressure reducing station
needs to be appropriately located within easements, tracts or public property for ownership
and maintenance and properly sited in relation to the elevation of lots to be served. The
plat drawing Preliminary Plat PLT08-0002, Sheets 1-7, Daley-Morrow-Poblete Inc.
September 18, 2012 shows the PRV to be appropriately located within the underdeveloped
right-of-way of Kennedy Avenue SE, off-site near the SE corner of the subject property.
11. With the installation of the water system pressure reducing station (PVR), a minimum 20-
foot wide all weather surface is required to provide the necessary city maintenance access
and vehicle turnaround (if a one-way access is constructed and a through access is not
provided). The PRV and associated maintenance access is proposed to be installed within
the undeveloped public street right-of-way of Kennedy AV SE, off-site to the east. This
undeveloped right-of-way contains an existing 10-foot wide dirt road for access to an
overhead electrical power line on wooden poles. The width of the right-of-way varies from
40 feet to 60 feet in width near the property.
12. Based on the Wetland Reconnaissance Letter, River Rock PRV Station, Sewall Wetland
Consulting, Inc. December 5, 2012, a wetland exists off-site. This linear wetland parallels
the eastern edge of a portion of this undeveloped right-of-way (Kennedy Avenue SE) east
of the site. This off-site wetland has the potential to be affected by project construction by
the construction of a minimum 20-foot wide all weather surface to provide the necessary
city maintenance access and vehicle turnaround (if appropriate) to the PRV.
13. The construction of the minimum 20-foot wide all weather surface to provide the necessary
city maintenance access and vehicle turnaround (if required) to the PRV station is eligible
for an exemption from the city’s buffer requirements of the critical area regulations under
ACC 16.10.040 “Exemptions and nonconforming uses”.
“ACC 16.10.040 Exemptions and nonconforming uses.
A. The following activities performed on sites containing critical areas as
defined by this chapter shall be exempt from the provisions of this chapter:
.
.
3. Normal and routine maintenance, operation, repair and reconstruction of
existing roads, streets, utilities and associated structures; provided, that
reconstruction of any structures may not increase the impervious area and may
not cause further encroachment on the critical area or its buffer, and may not
result in adverse impacts to surface water and ground water quality. Operation
and maintenance includes vegetation management performed in accordance
with best management practices that is part of ongoing maintenance of
structures, infrastructure, or utilities; provided, that such management actions are
part of regular and ongoing maintenance, do not expand further into the critical
area, are not the result of an expansion of the structure or utility, and do not
directly impact an endangered or threatened species;
4. Minor Utility and Street Projects. Utility or street projects which have
minor or short duration impacts to critical areas, as determined by the director in
accordance with the criteria below, and which do not significantly impact the
functions or values of a critical area(s); provided, that such projects are
constructed with best management practices and additional restoration measures
Agenda Subject – PLT08-0002
River Rock 4 Preliminary Plat
Page 7 of 25
are provided. Minor activities shall not result in the transport of sediment or
increased storm water. Such allowed minor utility projects shall meet the
following criteria:
a. There is no practical alternative to the proposed activity with less impact
on critical areas;
b. The activity involves the placement of underground piping, conduit, traffic
signal equipment, lighting equipment, utility pole(s), signs, anchor, or vault or
other small component of a utility or street facility;. . .”
14. The area of the proposed PRV maintenance road construction is identified as containing
the following critical areas: Category III wetland (Wetland Reconnaissance Letter, River
Rock PRV Station, Sewall Wetland Consulting, Inc. December 5, 2012) to the east and a
Class IV Landslide Hazard Area to the west. The area of the maintenance road
construction was not previously evaluated in the geotechnical report and a limited scope
supplement to the geotechnical report must ensure that the construction to widen the
maintenance access surface within the undeveloped right-of-way of Kennedy AVE SE does
not result in adverse impacts on geologic hazard areas or increase instability of slopes
above and below the public right-of-way. The additional geotechnical report has been
required in the SEPA decision.
15. The report Geotechnical Engineering Report Proposed Single Family Plat, 850 Oravetz
Road SE , GeoResources LLC, December 3, 2007 identifies site limitations for stormwater
management based on the soil characteristics, very limited infiltration capacity and storage
capacity and the existence of steep slopes and the extent of proposed earthwork. As a
result, there is a need for close coordination of the temporary and permanent storm water
management and the construction of the proposed stormwater system. The report
recommends addition evaluation of the site at the rough grading stage of construction and
appropriate management, detention and conveyance of stormwater to off-site discharge
location to the west.
16. The proposal is required to conform to the following City of Auburn regulations and
standards:
• ACC Title 10 – Vehicles and Traffic
• ACC Title 12 – Streets, Sidewalks and Public Works
• ACC Title 13 - Water, Sewer, and Public Utilities
• ACC Title 14 - Project Review
• ACC Title 15 – Buildings and Construction
• ACC Title 16 – Environmental
• ACC Title 17 – Subdivisions
• ACC Title 18 – Zoning
• ACC Title 19 – Impact Fees
• City of Auburn (Public Works) Construction Standards
• City of Auburn (Public Works) Design Standards
17. The proposal will not have significant adverse environmental impacts on fish and animals,
water, noise, air quality, environmental health, public services and utilities, and land use
provided the conditions of approval are met.
Agenda Subject – PLT08-0002
River Rock 4 Preliminary Plat
Page 8 of 25
18. On September 21, 2012 the Applicant submitted two plat modification requests from road
design standards pursuant to the process in ACC Section 17.18.010 with findings of fact
made pursuant to ACC Section 17.18.030. Plat modifications are the means through which
deviations from standards are reviewed.
• The Applicant has submitted request for deviations in order to use rolled curb to
provide flexibility in the location of lot driveways (rather than vertical curb)
• exceed 6% grade for public roadways and access tracts up to the maximum of 12%
(based on vested standards)
Transportation Division staff has reviewed the request and the City Engineer recommends
to the Hearing Examiner approval of the second request that in light of the modification
criteria and finds the requests are justified. The first request does not require a deviation
since the Applicant can accomplish the requested continuous access utilizing the City’s
standard depressed curb throughout the cul-de-sac in lieu of the rolled curb.
19. The proposed plat will require half-street improvements along the frontage of Oravetz RD
SE consistent with required public improvements pursuant to ACC 12.64A. Oravetz RD SE
is designated a "Minor Arterial" street. Direct lot access to a minor arterial is generally
avoided. The improvements will require dedication of an irregularly-shaped area as right-
of-way for completion of the half street improvements.
III. CONCLUSIONS
B. Auburn City Code: Title 17 Land Division Code
The project is vested to the subdivision code standards in effect at the time the application was
deemed complete in 2008. The subdivision standards were subsequently amended in 2009.
The following analysis is based on comparison to these 2008 standards and the criteria for
preliminary plat approval.
ACC Section 17.06.070 - Preliminary Plat Criteria
1. 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, parks, playgrounds and sites for schools and school grounds.
Staff Analysis
Adequate provisions have been or can be provided to serve the plat. Public utilities,
(stormwater, water and sewer) and public schools, and new public streets are available
and capable of serving the proposed plat.
The Applicant has submitted a conceptual utility plan (Sheet 3 of 7) Preliminary Plat
PLT08-0002, Sheets 1-7, Daley-Morrow-Poblete Inc. September 18, 2012 that has been
reviewed by the Public Works and Engineering staff to demonstrate the plat is capable of
being served by city utilities.
Storm - The plan shows that stormwater runoff originating from the new public street and
the access tracts is will be conveyed via catch basins and underground pipe. Piped runoff
then crosses the lots by easement to a proposed publicly dedicated storm pond providing
Agenda Subject – PLT08-0002
River Rock 4 Preliminary Plat
Page 9 of 25
water quality and quantity control that is to be constructed on the west side of the plat in
Tract D. Tract D is proposed to be approximately 38,932 square feet in area and provides
for a maintenance access to the bottom of each cell of this multi-cell pond. The pond,
maintenance access and its slope must meet city standards. Discharge from the pond will
be into the public storm system in Oravetz RS SE. Because the storm pond is at a highly
visible location, to ensure appropriate aesthetic treatment, the HOA shall maintain those
portions of the stormwater tract located outside the fenced pond boundary, or if no fence if
provided, outside the 10-year storm water surface elevation, as determined by the City
Engineer.
There are also existing storm drainage catch basins, which will be retained within the
existing right-of-way of Oravetz RD SE on either side of the existing curb return near the
southern part of the project frontage that will be retained. The existing storm line in
Oravetz RD SE will be extended northerly along the remaining lot frontage and new catch
basins installed to manage runoff from the street frontage improvements.
Stormwater from rooftops of the future houses will be addressed consistent with city
standards and the 2009 Surface Water Management Manual (SWMM) through on-site
infiltration (such as drywells, etc.) but more likely through connection to the storm system
because of infiltration limitations of the site soils.
Water - The conceptual utility plan also shows the extension of public water lines to serve
the site. The preliminary plat will require extension from the nearest water main which is
approximately 400 feet south of the SE corner of the plat at the existing north terminus of
Kennedy AVE SE. The extension will occur in the underdeveloped right-of-way of Kennedy
AVE SE. Near the SE corner, a pressure reducing station is required to be installed
because subject property and its ground surface elevation occur at the boundary of two
pressure zones of the city’s public water system. In order to adequately serve the
proposed lots, the installation of a pressure reducing valve/station (PRV) is required on the
new main looping through the property from Kennedy AV SE to bring water system
pressure within acceptable limits.
With the installation of the water system pressure reducing station (PVR), a minimum
twenty- (20) foot wide all weather surface is required to provide the necessary city
maintenance access and vehicle turnaround (if a one-way access is constructed and a
through access is not provided). The existing right-of-way is adequate to accommodate
the maintenance access but the physical driving surface needs to be widened to the future
PRV.
The water main will also be extended west, then north through proposed right-of-way and
easements through the plat to provide service to the individual lots and to provide fire
hydrants as required by city standards. The water system then would be interconnecting
with the existing water line in Oravetz RD SE.
As part of the water system the proposed project must provide fire hydrant meeting City of
Auburn spacing requirements.
Also, the two parcels off-site to the east (Parcel # 3121059048 and #3121059018) would
be connected to the new water line and the very long existing service line currently
providing service to Oravetz RD SE would be eliminated.
Agenda Subject – PLT08-0002
River Rock 4 Preliminary Plat
Page 10 of 25
Sewer - The submitted conceptual utility plan shows proposed sewer extension to serve
the site. The goal of the preliminary design of the sanitary sewer system for the preliminary
plat is to demonstrate that all City regulatory provisions for sanitary sewer service can be
met while reasonably insuring that subsequent changes to the preliminary plat footprint
(lots, tracts, right-of-way, and easements) will generally not be needed to accommodate
the final design and construction of the system during the civil plan review and final plat
process. The existing sewer line in Oravetz RD SE will required extension along the street
frontage, and roughly four laterals or “branches” to maximize opportunities for gravity
connection from the lots to the sewer system. The lower branch will serve the lowest level
of lots (Lots 7 & 8) the lower middle branch will require extension to serve Lots 11-14) the
upper middle branch will be extended in the new public street to serve Lots 2-6 and the two
lots to the east. The fourth “branch” will serve Lot 1 require extension to the NE corner of
the plat to meet city requirements for extension in accordance with the comprehensive
sewer plan. The design of the system must meet city standards for easements and
maintenance access, including maintenance vehicle turnarounds. .
Per an agreement between the property owner of the parcel northeast of this project and
the City of Auburn (King County Recording # 20081217000150), that owner is required to
connect to the public sewer system extended by via this project, and abandon the existing
long side sewer that now traverses proposed Lots 1-4. Also, the two parcels off-site to the
east (Parcel # 3121059048 and #3121059018) would be connected to the new sewer
system and the very long existing service line currently providing service would be
eliminated.
Streets - The existing site contains sidewalk developed to a previous standard along the
southern portion of the frontage of Oravetz RD SE. The extent of existing improvements is
shown on Sheet 1 of Preliminary Plat PLT08-0002, Sheets 1-7, Daley-Morrow-Poblete Inc.
September 18, 2012. “Half-street improvements” and the dedication of additional right-of-
way will be required to meet current city standards along the project frontage. There is an
existing curb return (rounded sidewalk for future intersection) that is near the south part of
the frontage. This is currently used for driveway access to the two lots located to the east
of the plat and to the one lot located to the south of the plat.
Primary access to the future lots will be from Oravetz RD SE by a proposed extension of
approx 360-foot length of new public street and three private access tracts. The original
plat submittal exceeded the city’s vested maximum road grade standards for a new public
street and traversed a 17% slope. A subsequent revision of the plat shifting the proposed
road north and more diagonal to the slope, submitted on September 18, 2012, reduced the
grade to an amount that can be authorized by deviations per City of Auburn Engineering
Design Standards Manual, Section 1.03 upon approval by the Hearing Examiner. The
Applicant submitted a request for deviations on September 21, 2012 in order to use rolled
curb to provide flexibility in the location of lot driveways (rather than vertical curb) and to
exceed 6% grade for public roadways and access tracts up to the maximum of 12% (based
on vested standards) (See the requested deviations, Exhibit 12).
The proposed public street is to be developed consistent with the City’s “Local Residential
Street Standard” with twenty-eight (28) feet of road surface within a fifty- (50) foot right-of-
way. Sheet 2 of Preliminary Plat PLT08-0002, Sheets 1-7, Daley-Morrow-Poblete Inc.
September 18, 2012 shows sight distance triangles and the adequate sight distance can be
accommodated at the intersection of the new street and Oravetz RD SE.
Agenda Subject – PLT08-0002
River Rock 4 Preliminary Plat
Page 11 of 25
In accordance with Section 10.01.3.1 and Table 10.02, of the Street Design Requirements,
of the City of Auburn Design Standards Manual, local residential streets are required to be
a minimum of 28 feet between curbs, and parking is allowed on one side of the street only
in order to allow adequate emergency vehicle access. "NO PARKING THIS SIDE" signs,
in accordance with City of Auburn Standard Details, shall be installed prior to occupancy of
structures on the site. Failure to provide the no parking signs will result in the street being
declared a Fire Lane and additional signage and painting will be required to meet Auburn
City Code ACC 10.36.175, Fire Lane Marking. Also, Fire Lane marking shall be installed
for proposed hammerhead turn-a-round at the end of Tract "C".
Access through the subject property to adjacent parcels - The previous history of land
divisions and boundary line adjustments associated with this property have resulted in two
developed lots and associated houses located to the east (Parcel # 3121059048 and
#3121059018) that are not part of the subject property but that currently access via a
shared east-west driveway through the proposed subdivision. An access easement, as
well as, utility service easements to these two lots granted by the Applicant, bisects the
subject property. The easements are shown and described on Sheet 1 of Preliminary Plat
PLT08-0002, Sheets 1-7, Daley-Morrow-Poblete Inc. September 18, 2012. The easement
provisions provide for the ability for these “easement(s) to be relocated at the sole
discretion and expense of the Grantor”.
The proposed change in access to these two lots and associated houses has been
reviewed by the city’s Transportation Division and the Valley Regional Fire Authority. The
result of reviews by both found it to be a general improvement. While different standard
apply to driveways than to public streets, the access driveway connections for the two
existing single family residential that currently utilize 41st Street SE would seem to improve
the fire access routes available via the new route of the new public street labeled: 46th
Court SE. The City Transportation Division also required conceptual information to
demonstrate that a gradual grade transition can be accommodated in the shared driveway
connecting these lots to 46th Court SE. Tract A, a 152 square foot access tract is proposed
to accommodate this driveway connection.
The two single family residences on an existing lot (Parcel #3121059020) located south of
the subject property currently use a gravel driveway for vehicle access that crosses the
subject property. The legal access is via an existing 20-foot wide access easement
(Recording # 9707230249) of which, ten (10) feet is located on the Subject Property and
ten (10) feet on the adjacent property off-site to the west. However, the existing gravel
access is not located completely located within the access easement. Also, an access
easement (Recording # 20090828001499) was previously granted across a portion of the
Subject Property to partially correct the circumstance and to coincide with the physical
location of the northern portion of the gravel driveway. See Easement # 1 on Sheet 1 of
Preliminary Plat PLT08-0002, Sheets 1-7, Daley-Morrow-Poblete Inc. September 18, 2012.
The preliminary plat proposes to widen the gravel access (existing driveway retained and
expanded) and for it be shared as an access to the off-site residences (Parcel
#3121059020) and as maintenance access to Tract D containing the storm pond. This
driveway would continue to connect to Oravetz RD SE at the existing location and curb
return.
The proposed change in access to this lot off-site to the south has been reviewed by the
City’s Transportation Division of the Public Works Department and the Valley Regional Fire
Agency (VRFA). The VFRA considers the existing access via the gravel driveway “non-
Agenda Subject – PLT08-0002
River Rock 4 Preliminary Plat
Page 12 of 25
conforming” for fire access. An on-site review of this access driveway revealed that for
most of its length the driveway would not support a modern fire vehicle apparatus. The
width, grade, and driving surface cause this driveway to be of marginal use for fire
apparatus access. The proposed changes to the driveway entrance from Oravetz Road
SE and connection to the existing driveway appear to improve the access for larger
vehicles.
The City Transportation Division reviewed the proposed access, VRFA comments, and city
standards and believes that accessing the existing curb return intersection shown on Sheet
3 of Preliminary Plat PLT08-0002, Sheets 1-7, Daley-Morrow-Poblete Inc. September 18,
2012 meets city standards (Section 10.04.4.3 of the City of Auburn (Public Works) Design
Standards Manual) which requires the angle of the driveway throat to be not less than 85
degrees. According to Section 10.04.4.3 of the Design Standards the angle of the
driveway intersecting a public street shall not be less than 85 degrees – unless an access
control device is allowed to be utilized such as a median, “c” curb or “pork chop”. The
Transportation Division indicates none of these devices are in place or will be allowed at
that location. The access via the location of the pre-existing access easement (Recording
#9707230249) that is not in use, would not meet the Design Standards Manual for the
approach angle of the driveway to Oravetz RD SE (approximately 45 degree angle).
The proposal by this plat as illustrated on Sheet 3 of Preliminary Plat PLT08-0002, Sheets
1-7, Daley-Morrow-Poblete Inc. September 18, 2012 accommodates the existing driveway
location of this off-site property located to the south (Parcel #3121059020) via the current
driveway location and represents the best solution in light of the current circumstances.
The proposed preliminary plat does not adversely affect either the off-site property owner’s
existing gravel access or adversely affect the property owner’s existing easements. The
plat proposal instead, is providing a wider gravel surface and the newer construction of the
access to meet city standards for loading of maintenance vehicles accessing the storm
ponds in Tract D, will result in an improved condition.
The project will need to include provisions to accommodate continued access to two lots
located to the east and one lot located to the south that currently access through the
subject property by private easements. The continued access is anticipated to be
addressed and ensured through the review and approval of civil plans and review and
approval of the final plat.
Park - The plat does not have the number of lots (50 and more dwelling units) and
anticipated population to trigger the dedication of park land. The project will adequately
mitigate park impacts through payment of park impact fees at building permit issuance or
as may be deferred by City Ordinance #6455.
Schools – School impacts are anticipated to be mitigated through the payment of school
impact fees. School impact fees in accordance with ACC Chapter 19.10 are collected at
building permit issuance or as may be deferred as allowed by City Ordinance #6455. This
project is located within the Auburn School District. The Riverside High school is located
across the street and south of the site. Ilalko Elementary is located along Oravetz RD SE,
approximately 0.5 mile to the southeast. There are no known school bus stop locations
within the vicinity of proposed project. For safe walking routes sidewalks will be
constructed on both sides of the new residential street and along Oravetz RD SE.
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As discussed above, 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, parks, playgrounds and sites for schools and school
grounds consistent with this criteria. Staff believes the preliminary plat meets these
criteria.
2. Conformance of the proposed subdivision to the general purposes of the
Comprehensive Plan.
Staff Analysis
The proposed preliminary plat is in conformance with the general purpose of the
Comprehensive Plan and it goals, objectives, and policies. The proposal is also consistent
with specific sub-elements of the Plan and the land use mapped designation.
Comprehensive Land Use Map
The site is designated “Single Family Residential” by the adopted Comprehensive Land Use
Map, Map No. 14.1
This “Single Family Residential” category is explained in Chapter 14, “The Comprehensive
Plan Map”. The stated purpose of this category is to “designate and protect areas for
predominantly single family dwellings.” Implementing regulations should provide for an
appropriate range of lot sizes, clustered and mixed housing types as part of a planned
development.”
The compatible uses appropriate for this designation include single family residences and
uses that serve or support residential development, such as schools, daycare centers,
churches and parks shall be considered appropriate and may be permitted on a conditional
basis. Other public buildings and semi-public uses may be permitted if designed and laid
out in a manner which enhances rather than detracts from the residential character of the
area. In locating such uses, however, special care shall be given to ensuring adequate
parking, landscaping, and traffic circulation with a minimum of conflict with residential
uses. Uses which generate significant traffic (such as large churches) should only locate
on developed arterials in areas zoned for institutional uses.
The description of this category states planned developments should be favorably
considered in these designations in order to allow optimal flexibility. In providing such
flexibility, the emphasis should be on small alley-loaded lot single family development,
limited low density multifamily housing and a mixture of types, and design diversity should
be sought. Except where conditional use permits have been previously granted, alternate
structure types should not exceed more than 40 percent of the units, and alternative
structures should in most cases contain no more than four dwelling units each. However,
where substantial offsetting community benefits can be identified, such alternative
structures may be allowed to contain more than three units each.
The preliminary plat is providing additional lots for inventory of single family housing
consistent with the general intent of the Single Family Residential land use designation of
the site.
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Residential development is also addressed in Chapter 3, Land Use, of the Comprehensive
Plan. This chapter contains goals, objective and policies guiding residential development;
those pertinent to this application are as follows:
“Land Use Goal 7: Residential Development
To emphasize housing development at single family densities, in order to
reestablish a mix of housing types appropriate for a family oriented community,
while recognizing the need and desire for both lower density and higher density
housing appropriately located to meet the housing needs of all members of the
community.
“LU-17 Residential densities in areas designated for single family
residential use should be no greater than 7 units per net acre. These
areas should be served with good transit availability (1/4 mile or less to a
route with at least half hour service). Accessory dwelling units should be
permitted to allow increased densities. The bulk of the single family
residential community should be developed at a density of between 4 and
7 dwelling units per net acre. Increased density is achievable through
flexible development standards, if certain criteria are met, as established
in city code.”
“Objective 7.3. To promote the development of quality single family
neighborhoods which relate the design and types of residential areas to
important natural and manmade features.”
“LU-21 Residential development should be related to topography,
circulation, and other amenities, as guided by policies of this Plan.
LU-23 The development of new neighborhoods should be governed by
development standards which allow some flexibility. Flexibility should be
considered to encourage compact urban development, to provide
protection of critical areas and resource lands (including, but not limited
to, agricultural resource lands, cultural resources, forest resource lands,
mineral resource areas (Map 9.4) hillsides or wetlands), and to facilitate
non-motorized transportation. Increased density is achievable through
flexible development standards, if certain criteria are met, as established
in city code.
LU-24 The development of residential areas should recognize the
importance of community and public facilities in developing a sense of
neighborhood and community.”
“LU-28 Areas abutting major arterials should be carefully planned to avoid
potential conflict between the development of the arterial and single
family uses. Single family uses in such areas should be platted in a
manner which orients the units away from the arterial. Where such
orientation is not possible, a transition area should be allowed for non-
single family uses which reduce total driveway connections to the arterial.
In any case, non-motorized access between residential areas and
arterials should be provided. In areas with existing single family
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developments, substantial flexibility can be permitted for street front
buffering.”
“Objective 7.4. To establish new neighborhoods in a way that will minimize the
potential for intrusion of incompatible uses.”
“LU-29 Development design should utilize and preserve natural features,
including, but not limited to, topography and stands of trees, to separate
incompatible land uses and densities.”
The density for fourteen single family lots on 6.03 acres is 2.32 dwelling units per acre
under the former code definition of “Density” (ACC 18.04.300). This density is slightly less
than prescribed for the designation but density is allowed to vary by the permissive
language (“The bulk of the single family residential community should be developed at a
density of. . .”). The lesser density is appropriate in light of the site topography. The plat
takes advantage of proximity to adjacent schools (Riverside High School, Ilalko
Elementary), and nearby parks (Roegner Park, Mill Pond Park), and natural resources
(Game Farm Wilderness Park and the White River).
Lakeland Hills Special Plan Area
The site is within the Lakeland Hills Special Planning Area adopted as a sub-area plan of
the City’s Comprehensive Plan. The City’s Comprehensive Plan adopted in 1986, provided
for several nodes identified as “Special Plan Areas” (Map # 14.2) to allow large areas
within the City, under a single or a coordinated management, to be developed as a
planned unit. This designation was also applied when flexibility is needed or when there is
uncertainty regarding how an area may be most appropriately developed in the future.
The Lakeland Hills Plan was specifically adopted by Resolution # 1851 in April 1988 and is
an element of the Comprehensive Plan. The Plan covers the approximately 458 acres of
the Lakeland Hills development which falls within the King County portion of the City. The
Plan calls for a mix of residential uses including single- and multi-family housing as well as
supporting recreational, commercial, public and quasi-public uses. The plan calls for
phasing of development in coordination with the provision of necessary urban services.
The Plan is consistent with and implements the key mitigation measures related to land
use described in the Environmental Impact Statement described in the Final Environmental
Impact Statement for the Lakeland Hills Development (October 1981).
The Plan sets forth the appropriate comprehensive Plan designations and zoning
classifications for the portion of the development lying within the City of Auburn. The plan
also contains a number of individual policies specifying the preferred development pattern
in relation to topography, the provision of future park land, coordination of the future
street system and the provision of utilities.
Many of these policies of this Sub-Area Plan were established when the area was first
developing and now this site is one of the few remaining vacant, undeveloped properties
covered by the Plan. In general, the Plan provides that lower elevations and flatter slopes
are suitable for multiple-family residential while upper elevations are suitable for single
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family. The subject property was originally identified for multiple family development, but
a change was subsequently approved by the City. The provision of park land originally
specified by the Sub-Area Plan has subsequently been provided by developer’s provision of
the Mill Pond Park (to the west) and the City’s acquisition and development of the Roegner
Park (across the Street and along the south bank of the White River) and Game Farm
Wilderness Park. Additional open and recreational space is provided by Auburn Riverside
High School and its running track and ball fields situated on the north side of Oravetz Road
SE and, east and west of the school building in the vicinity. Significant water, sewer and
storm utility system upgrades, such as a new pump stations, main line extensions and new
detention and treatment facilities (Mill Pond Park), have also been completed concurrently
as development has progressed within the Sub-Area.
The proposed preliminary plat is in conformance with the general purpose of the Sub Area
Plan of the Comprehensive Plan and it goals, objectives, and policies.
3. Conformance of the proposed subdivision to the general purposes of any other
applicable policies or plans that have been adopted by the City Council.
Staff Analysis
The project is consistent with the Non-Motorized portion of the Comprehensive
Transportation Plan (which is also the transportation Element of the Comprehensive Plan).
Sidewalks will be constructed along both sides of the internal street and along the project
frontage of Oravetz RD SE. Safe walking conditions will be created through the
construction of sidewalks.
The project has been reviewed by the Utility Divisions of the Public Works Department for
general conformance with City standards and the consistency with the guidance of the
individual Comprehensive Utility Plans (Stormwater, Water and Sewer). The purpose of
this review is to ensure that City regulatory provisions for utility service can be met while
reasonably insuring that subsequent changes to the preliminary plat footprint (lots, tracts,
right-of-way, and easements) will generally not be needed to accommodate the final
design and construction of the utility systems during the civil plan review and final plat
process. The project was determined by these Public Works Department reviews to be
consistent with the individual Comprehensive Utility Plans.
The preliminary plat will be consistent with the Auburn Parks, Recreation and Open Space
Plan through payment of parks impact fees.
4. Conformance of the proposed subdivision to the general purposes of the Land
Division Ordinance as enumerated in ACC Section 17.02.030.
Staff Analysis
The preliminary plat is consistent with the broad purpose statements of the Land Division
Ordinance as enumerated in ACC Section 17.02.030.
ACC 17.02.030 Purpose.
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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
welf are 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;
B. Promote safe and convenient travel by the public on streets and
highways;
C. Promote the effective use of land;
D. Provide for adequate light and air;
E. Facilitate adequate provision for water, sewerage, storm drainage, parks
and recreational areas, sites for schools and school grounds, and other public
requirements;
F. Provide for proper ingress and egress;
G. 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;
H. Adequately provide for the housing and commercial needs of the citizens
of the state and city;
I. Require uniform monumenting of land divisions and conveyance by
accurate legal description;
J. Implement the goals, objectives and policies of the Auburn
comprehensive plan.
The preliminary plat of River Rock 4 is 14-lot subdivision that is consistent with the Single
Family Residential and Lakeland Hills Comprehensive Plan designations and the vested R1,
zoning classification and thus an effective use of land with adequate provision for access to
light and air. The fourteen lots are proposed to be developed as single-family residences
that provide additional housing stock for the city and state. Adequate provisions for safe
access, provision of utilities including water, sewer, and storm drainage are provided as
part of this project. The City is the service provided for these public utilities.
This project is responsible for street frontage improvements including sidewalk to enhance
pedestrian access of the project that will eventually connect to the city parks to the west.
Safe walking conditions and methods of ingress/egress are provided. Sidewalks will be
constructed along both sides of the internal road.
The plat has been processed in accordance with the regulations of the Auburn City Code,
other city plans, policies and land use controls, and RCW Chapter 58.17.
5. 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.
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Staff Analysis
Auburn City Code: Title 18 Zoning
The City has considered the project vested to the R1, Residential Zoning district standards
(ACC 18.12., based on a determination of completeness in 2008). The current zoning
classification of the site is R5, Residential Five Dwelling Units per Acre.
The preliminary plat is subject to the following standards. The proposed plat meets or is
capable of meeting the following zoning code standards.
ACC 18.12.040 (R1, Residential) Development Standards
Development Standards
A. Minimum lot area: eight thousand (8,000) square feet;
B. Minimum lot width: seventy-five (75) feet;
C. Minimum lot depth: one hundred (100) feet;
D. Maximum lot coverage: thirty-five (35 %) percent;
E. Minimum yard setbacks;
1. Front: twenty-five (25) feet;
2. Side, interior: for lots 75 feet or wider one side may be five (5) feet and
the other ten (10) feet; for lots less than 75 feet wide; each side may be
five (5) feet;
3. Side, street: ten (10) feet
4. Rear: twenty-five (25) feet
F. Maximum building height:
5. Main buildings thirty (30) feet;
6. Access buildings sixteen (16 feet).
The submitted site preliminary plat meets the above requirements for lot area, width and
depth. Setbacks, lot coverage, and building height will be reviewed at the time of building
permits for each individual lot.
Per ACC 18.52.020, a minimum of 2 parking spaces per single-family residence will be
required to be provided within each lot at the time of development.
City’s (Public Works) Design and Construction Standards Manuals
The plat has been or is capable of being designed in accordance with applicable City
standards including the City’s Design and Construction Standards Manuals, with the
exception of the requested plat modifications (Deviations from the City’s (Public Works)
Design Standards Manual).
Requested Plat Modifications Per ACC 17.18.010, the Hearing Examiner may approve a
modification of any standard or specification established or referenced by ACC 17.14 or
established or referenced in the city's (Public Works) 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.
Per the deviation request dated September 21, 2012, the Applicant proposes the following
deviations from city's (Public Works) Design Standards:
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• The Applicant has submitted request for deviations in order to use rolled curb to
provide flexibility in the location of lot driveways (rather than vertical curb)
• exceed 6% grade for public roadways and access tracts up to the maximum of
12% (based on vested standards)
Transportation Division staff has reviewed the request and the City Engineer recommends
approval of the second request that in light of the modification criteria and finds the
requests are justified. The first request does not require a deviation since the Applicant
can accomplish the requested continuous access utilizing the City’s standard depressed
curb throughout the cul-de-sac in lieu of the rolled curb.
In addition to constructing new accesses to the proposed lots, the project will need to
include provisions to accommodate continued access through the subject property to two
lots located to the east and one lot located to the south that currently access through the
subject property by private easements. The continued access is anticipated to be
addressed and ensured through the review and approval of civil plan and review and
approval of the final plat process.
6. 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
For the general development of the site and vicinity a Final Environmental Impact
Statement (EIS) for the Lakeland Hills Proposed Residential Community was issued by the
City in October of 1981.
For the specific development proposal, a Mitigated Determination of Non-Significance
(MDNS) (City File #SEP08-0007) was issued on March 15, 2013. The City did not receive
any comments in response to observance of the public comment period. Compliance with
the mitigation measures of the SEPA decision and the recommended conditions of
preliminary plat approval will assure that the proposal will not have an adverse impact on
the environment.
Wetland – The site is not shown on city’s wetland inventory maps and wetlands were not
identified by city environmental staff in response to a field visit. During processing
wetlands were investigated for an off-site area that could be disturbed by plat construction.
Based on the Wetland Reconnaissance Letter, River Rock PRV Station, Sewall Wetland
Consulting, Inc. December 5, 2012, a wetland exists off-site. This linear wetland parallels
the eastern edge of a portion of this undeveloped right-of-way (Kennedy Avenue SE) east
of the site. The buffer of this off-site wetland has the potential to be affected by project
construction of PRV maintenance access road as described in the Findings of Fact.
The wetland appears to be combination of slope and depressional seep type, shrub-scrub
wetland that has become impounded by the existing road fill prism. According to the
wetland letter, the proposed off-site construction of the maintenance access to the off-site
PRV station necessary for provision of water service to the plat would be within the
minimum 25-foot buffer appropriate for a Category 3 Wetland. While the wetland report
describes the construction of a 10-foot wide maintenance access, a minimum 20-foot wide
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access is required to provide for sufficient access for the type and size of maintenance
vehicles accessing the PRV station.
The wetland report identifies that the proposed construction may be subject to one of more
exemptions from the city’s critical area regulations under ACC 16.10.040 since it occurs
within an existing right-of-way that is currently used for maintenance access to a utility
(overhead electrical lines) and is proposed to be modified for purpose of access to a utility.
However, even if an exemption applies additional investigation of the wetland resource and
potential impacts will be required to ensure that exempt activities occurring in or near a
critical area comply with the purpose and intent of the standards and to consider on-site
construction alternatives that avoid or minimize significant adverse impacts. A final
mitigation plan will be required, reviewed, and approved prior to grading permits and civil
plan approval being issued.
Geologic Hazard Areas - The irregular 6.03 acre site measures approximately 698 feet
north to south and varies from 442 to 321 feet east to west. The site varies in elevation
from 210 feet near the NE corner to 110 feet near the southwest corner. The site is
dominated by a northwesterly facing hillside varying generally from 10% to 21% slopes.
The site is forested with scattered trees and mature understory vegetation. The forested
area is bisected by drainage and shared driveway within an easement roughly aligned east-
west accessing two lots and developed houses that are off-site east of the plat. The two
lots and houses were originally part of the subject property but segregated by past
boundary line adjustments (BLA07-0005, Recording Number 20070904900009 and BLA09-
0002, Recording Number 20090908900003.)
The proposed construction will require significant grading and clearing of a majority of the
site. The checklist application response indicates grading will be in excess of 500 cubic
yards and will seek to balance cuts and fills to the extent practical. However, the central
portion of the site will be cleared and graded for construction of the cul-de-sac public street
and the installation of utilities to serve future lots. Additional clearing and grading will be
required for installation of public sewer line along the northern boundary of the plat, a public
water line and pressure reducing station near the southern boundary of the plat and
stormwater drainage ponds and facilities along the western boundary of the plat. Retaining
walls of up to 8 feet in height and approximately 320 feet and 240 feet in length are
proposed along the eastern boundary of the plat where it abuts the two off-site lots. Also, a
retaining wall of up to four feet in height and approximately 80 feet in length is proposed
along the street frontage of Oravetz Road SE.
The report Geotechnical Engineering Report Proposed Single Family Plat, 850 Oravetz
Road SE , GeoResources LLC, December 3, 2007 analyzes the available geologic;
hydrogeologic; and geotechnical data for the site area, conducted a site reconnaissance,
and excavated test pits. Using this information, the report evaluates consistency with the
city critical area regulations, provides recommendations for grading/earthwork, for soil
bearing capacity, providing geotechnical recommendations for retaining walls, site drainage
and site’s stormwater system.
The Report notes the ground surface at the site generally slopes between 15 and 30% down
to the west. The slope eventually ends at the White River, which is over 500 feet west of the
site and separated by a road, ball fields and a riverfront park. The ground surface at the
extreme east end of the site behind the existing residences and off-site to the east at
inclinations ranges from 25 to 50%. The steeper slopes to the east are related to the
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flattened area of the undeveloped roadway of Kennedy Avenue SE and considered to be
engineered fill slopes by the report.
The report also compares the site conditions to the city’s critical area regulations. The report
notes that based on a review of soil data, the site soils technically meet the technical criteria
of an erosion hazard area. However, the report notes that potential erosion hazard is not a
limiting factor for the proposed roadway construction but removal of vegetation should be
minimized and limited to active construction areas. Temporary and permanent erosion
controls should be installed and maintained during construction and as soon as practical
thereafter to limit exposed areas and protect receiving waters.
Based on the city’s classifications of landslide hazard areas, the geotechnical report
concludes that although the site exceeds 15 to 40 percent slopes (criteria), there are not
zones of emergent water and there are no active landslide areas. The site is stable relative
to deep seated failures in their present configuration. Properly designed and constructed
cuts and fill (grading) with the installation of stormwater controls, foundations and retaining
walls will improve slope stability at the site. In addition, no disturbance of the steeper slope
areas is proposed.
The geotechnical report also considers the relationship to seismic hazard areas. Based on
the subsurface conditions observed at the site, the report identifies that the site soils are not
susceptible to liquefaction. The near surface soils are generally in a dense to very dense
condition and the static water table is located well below the site. Shaking of the already
dense soil is not apt to produce a denser configuration and subsequently excess pore water
pressures are not likely to be produced.
The geotechnical report contains recommendations on the conduct of earthwork. Grading of
the site will be required to reach design grades. The site soils are moisture sensitive and
will be difficult to impossible to compact adequately when above the optimal moisture
content or wet weather. Excavation extending into the areas with over-optimal (moisture)
soil, it may be necessary to over excavate and replace with soil material with quarry spalls,
or to aerate naïve soils prior to compaction. Prior to placement of fill, the exposed subgrade
areas would be compacted to a firm and unyielding surface. And when not compactable
removed and replaced with structural fill. Geotechnical expert inspection and evaluation is
recommended to evaluate exposed subgrade conditions.
The on-site soils are generally not suitable for reuse as structural fill when above optimal
moisture content. Reuse will only be possible in prolonged dry weather conditions.
The geotechnical report contains recommendations on stormwater management. The
geotechnical report notes that stormwater should not be infiltrated at the site. The soils
have very limited natural infiltration and storage capacity. Stormwater runoff should be
controlled and managed and tight-lined to an appropriate discharge location.
Because the construction to widen the existing maintenance road to provide sufficient
maintenance access to serve the future water system PRV station was not identified at the
time the geotechnical report was prepared, there is need to ensure that the construction to
widen the maintenance access surface within the undeveloped right-of-way of Kennedy AVE
SE does not result in adverse impacts on geologic hazard areas or increase instability of
slopes above and below.
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Groundwater protection zone - The project site is located in Groundwater Protection Zone
4. ACC 16.10.120(A)(5)(b) requires that for projects located within Groundwater
Protection Zone 4, property owners shall implement best management practices
(BMP) for water resource protection. At a minimum, this includes the following
BMPs listed in the City of Auburn Surface Water Management Manual:
• BMP C101 - Preserving Natural Vegetation
• BMP C102 - Buffer Zone
• BMP C103 - High Visibility Plastic or Metal Fence
• BMP C120 - Temporary and Permanent Seeding
• BMP C153 - Material Storage, Delivery and Containment
• BMP C160: Certified Erosion and Sediment Control Lead
RECOMMENDED CONDITIONS OF APPROVAL:
Based on the Findings of Fact and Conclusions of the staff report, staff recommends that the
Hearing Examiner approve the Preliminary Plat with the following conditions:
The following six mitigation measures as identified in the Mitigated Determination of Non-
Significance (MDNS) (File # SEP08-0007) shall be incorporated as conditions of the preliminary
plat approval.
1. Concurrent with the review of land clearing, grading, or public facility extension
approvals a limited scope Final wetland mitigation plan is required to be prepared and
submitted to the city for review and approval. The limited scope plan shall address the
location of the wetland, the wetland classification, functions and values and to ensure
consistency with the purpose and intent of the city critical areas regulations, consider on-
site alternatives that avoid or minimize significant adverse impacts, as required for
exempt activities consistent with ACC 16.10. The report shall be reviewed and approved
prior to permit issuance and or approval. The mitigation plan can be part of the
approved construction plan set.
2. Concurrent with the review of land clearing, grading, or public facility extension
approvals a limited scope geotechnical critical areas report shall be provided for review
and approval by the City. The report shall address the location of any on-site or
proximate off-site critical landslide hazards as defined by Chapter 16.10 ACC, and
provide recommendations for slope stability BMPS, erosion control and protective
buffers, as appropriate, related to the construction to widen the existing maintenance
road in order to provide sufficient maintenance access to serve the future water system
PRV station. The future water system PRV station was not identified at the time the
geotechnical report was prepared, so there is need to ensure that the construction to
widen the maintenance access surface within the undeveloped right-of-way of Kennedy
AVE SE does not result in adverse impacts on geologic hazard areas or increase
instability of slopes above and below. The report shall be reviewed and approved prior
to permit issuance and or approval.
The project shall implement the recommendation of the geotechnical report:
Geotechnical Engineering Report Proposed Single Family Plat 850 Oravetz Road SE,
GeoResources LLC, December 3, 2007. In particular a geotechnical engineer shall
evaluate the exposed subgrade conditions after removal of the vegetation and topsoils
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and prior to placement of structural fill and provide a report to the city prior to continuing
earthwork operations.
3. The future home owner’s organizations shall maintain those portions of the stormwater
tract (Tract D) located outside the fenced pond boundary, or if no fence if provided,
outside the 10-year storm water surface elevation, as determined by the City Engineer.
4. Prior to issuance of clearing or grading permits, a grading plan for grading and clearing
necessary for both the construction of infrastructure such as roads and utilities and for
lot grading shall be prepared, submitted and approved by the City of Auburn. The
purpose of the plan is to accomplish the maximum amount of grading at one time to limit
or avoid the need for subsequent grading and disturbance, including grading of
individual lots during home construction. The plan shall identify the surveyed boundary
of the crest slopes for the site's 40% or greater slopes. This plan shall show quantities
and locations of excavations, and embankments, the design of temporary storm
drainage detention system, and methods of preventing drainage, erosion and
sedimentation from impacting adjacent properties, natural and public storm drainage
systems and other nearby sensitive areas. All the measures shall be implemented prior
to beginning phased on-site filling, grading or construction activities. The Applicant's
grading plans shall be prepared in conjunction with and reviewed by a licensed
geotechnical engineer. The geotechnical engineer shall develop and submit, for the
City's review, specific recommendations to mitigate grading activities with particular
attention to developing a plan to minimize the extent and time soils are exposed on site
and address grading and related activities during wet weather periods (the period of
greatest concern is October 1 through March 31). The plans shall show the type and the
extent of geologic hazard area or any other critical areas as required in chapters 16, and
18 of the International Building Code (IBC).
5. Upon completion of rough grading and excavation, the Applicant shall have a geo-
technical engineer re-analyze the site and determine if new or additional mitigation
measures are necessary. A revised geo-technical report shall be submitted to the City
of Auburn for review and approval by the City Engineer. Recommendations for areas
where subsurface water is known or discovered shall be given particular attention by the
geotechnical engineer and coordinated with the project engineer responsible for the
storm drainage system design.
6. The proposed new public street internal to the plat is proposed as a “Local Residential
Street” 28 feet in width. As a result, in accordance with Section 10.01.3.1 and Table
10.02, Street Design Requirements, City of Auburn Construction Standard, local
residential streets are required to be a minimum of 28 feet between curbs and parking is
allowed on one side of the street only. "NO PARKING THIS SIDE" signs, in accordance
with City of Auburn Standard Details, shall be shall be shown to be installed on the civil
plans for approval and shall be installed prior to occupancy of structures on the site.
Failure to provide the no parking signs will result in the street being declared a Fire Lane
and additional signage and painting will be required to meet Auburn City Code
10.36.175, Fire Lane Marking.
7. The proposed fire hydrant shown located in front of Lot # 4 shall be located in front of Lot
# 2 to maintain residential hydrant spacing consistent with city standards, or alternative
as approved by the City Engineer.
Agenda Subject – PLT08-0002
River Rock 4 Preliminary Plat
Page 24 of 25
8. Fire Lane marking in accordance with city standards shall be shown to be installed on
the civil plans and shall be installed prior to occupancy of structures on the site for the
proposed hammerhead turn-a-round at the end of Private Access Tract "C".
9. There is a ten foot (10’) private sanitary sewer easement noted along the boundary
between Lot 8 and Tract D. Since there are two sewer laterals, and two “grantees,” two
easements will be needed, and each must extend five feet (5’) on each side of each pipe
or alternative as approved by the City Engineer.
10. Auburn Design Standards (Section 8.01.2.2.I) require that an all-weather maintenance
road be provided to access manholes located outside the paved roadway. The
approved civil plans must show access to sanitary sewer manhole (SSMH) #3, or
alternative as approved by the City Engineer.
11. Provide a turn-around area for maintenance vehicles accessing sanitary sewer manhole
(SSMH) #8, or suitable alternative as approved by the City Engineer which must be
shown on the civil plans for approval.
12. The flow from the sewer line between SSMH#9 and SSMH#2 must reverse direction to
enter the downstream pipe. The Applicant may construct that line in the roadway using
HDPE pipe and a curved alignment. That alignment would allow the flow to enter the
manhole at 90-degrees to the downstream flow and make the proposed drop connection
unnecessary. The Final design shall be as approved by the City Engineer.
13. Due to the difficulty in repairing and/or replacing sewer lines on steeper slopes, the City
will require a wider thirty foot (30') easement (rather than typical 15-foot easement) on
the steep slope on the north side of the project.
14. In order to ensure the accurate placement of the home/structure(s) in relationship to the
setbacks required from property lines, easements or other similar features associated
with a lot, the City's Building Official may require that all applicable corners of the
structure be surveyed and staked prior to the pouring of footings or foundations.
15. Vehicle access to Lots 7 and 8 shall only be allowed by Access Tract C.
16. No direct Lot access to Oravetz RD SE shall be allowed from Lot 1 and Lot 14. These
lots must access the new proposed plat public street (Shown as 46th Court SE).
17. The plat modification related to the exceed 6% grade for public roadways and access
tracts up to the maximum of 12% (based on vested standards) is approved.
18. The project must include provisions to accommodate continued access to two lots
located to the east (Parcel # 3121059048 and #3121059018) and one lot located to the
south (Parcel #3121059020) that currently access through the subject property via
private easements. The continued access to the adjacent parcels shall generally be
consistent with the proposal illustrated on the preliminary plat (Preliminary Plat PLT08-
0002, Sheets 1-7, Daley-Morrow-Poblete Inc. September 18, 2012) and include
provision of Tract A for the east lots and may require modification of the existing access
easement (Recording # 20090828001499) previously granted across a portion of the
Subject Property to coincide with the physical location of the northern portion of the
gravel driveway for the southern lot.
Agenda Subject – PLT08-0002
River Rock 4 Preliminary Plat
Page 25 of 25
19. During construction and development, the Applicant shall observe best management
practices as required by ACC 16.10.120(A)(5)(b) due to the project’s location within
Groundwater Protection Zone 4. At a minimum, this includes the following BMPs listed
in the City of Auburn Surface Water Management Manual:
• BMP C101 - Preserving Natural Vegetation
• BMP C102 - Buffer Zone
• BMP C103 - High Visibility Plastic or Metal Fence
• BMP C120 - Temporary and Permanent Seeding
• BMP C153 - Material Storage, Delivery and Containment
• BMP C160: Certified Erosion and Sediment Control Lead
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.
List of Exhibits
Exhibit 1 Staff Report
Exhibit 2 2007 Aerial Photo of Site and Vicinity
Exhibit 3 Preliminary Plat Application and Materials
Exhibit 4 Preliminary Plat PLT08-0002, Sheets 1-7, Daley-Morrow-Poblete Inc. September
18, 2012
Exhibit 5 Combined Notice of Application, Notice of Public Hearing, and SEPA
Determination of Non-Significance,
Exhibit 6 Revised Environmental Checklist Application, SEP08-0007, Daley-Morrow-
Poblete Inc. July 22, 2011
Exhibit 7 Affidavits for Publishing, Mailing, and Posting
Exhibit 8 FEIS for Lakeland Hills Residential Development, City of Auburn, October 1981.
(Due to the age and large number of pages, this document has not been
duplicated for distribution to all parties. This document is available for review at
City’s Customer Service Center at 1 East Main Street, Auburn WA 98001, or
upon request)
Exhibit 9 Letter of Complete Application, dated June 14, 2006
Exhibit 10 Geotechnical Engineering Report Proposed Single Family Plat 850 Oravetz Road
SE, GeoResources LLC, December 3, 2007
Exhibit 11 Wetland Reconnaissance Letter, River Rock PRV Station, Sewall Wetland
Consulting, Inc. December 5, 2012
Exhibit 12 Letter Request for Deviations from City (Public Works) Design Standards related
to the River Rock Preliminary Plat, Daley-Morrow-Poblete Inc. Received
September 21, 2012 and Exhibit A.
Exhibit 13 City Engineer’s Recommendation for Engineering Deviation Requests, October
30, 2012.
Exhibit 14 Photographs of undeveloped Kennedy Road SE right-of-way looking north and
south in the vicinity of the future PRV and maintenance road
2007 Aerial Photo
Printed Date:
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.
Map Created by City of Auburn eGIS
4/10/2013
Exhibit 8 FEIS for Lakeland Hills Residential Development, City of
Auburn, October 1981.
(Due to the age and large number of pages, this document has not been
duplicated for distribution to all parties. This document is available for review at
City’s Customer Service Center at 1 East Main Street, Auburn WA 98001, or
upon request)
December 5, 2012
Jason Cole
7202 Quincy Avenue SE
Auburn, Washington 98092
RE: River Rock – PRV Station access road
SWC Job#12-145
Dear Jason,
At your request, I inspected the location of the proposed gravel access road near the
terminus of Kennedy Avenue North, in the City of Auburn, Washington. The
investigation of the area consisted of a reconnaissance level review and did not include
any delineation or precise mapping.
I inspected the area of the proposed gravel access road in July of 2012. The site was
reviewed using methodology described in the Washington State Wetlands Identification
Manual (WADOE, March 1997). This is the methodology currently recognized by the
City of Auburn and the State of Washington for wetland determinations and delineations.
The site was also inspected using the 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.
Observations
The proposed access road will be located on top of an existing gravel road that provides
access to the existing power line that passes along the same alignment. The project
consists of placing gravel over the existing poorly maintained road to allow access to a
proposed pressure relief valve to be located at the southeast corner of the proposed River
Rock plat.
The majority of the road currently has patches of Himalayan blackberry along its length.
At a point near the proposed connection near the southeast corner of the site, there is a
small scrub-shrub wetland located along the east side of the existing gravel road.
Sewall Wetland Consulting, Inc.
27641 Covington Way SE #2 Phone: 253-859-0515
Covington WA 98042 Fax: 253-852-4732
River Rock
Sewall Wetland Consulting, Inc.
December 5, 2012
Page 10
Above: Map showing approximate location of the small wetland near the proposed
gravel access road.
This wetland is appears to be a combination slope and depressional seep-type wetland
that has become impounded by the existing road fill prism.
This wetland is vegetated with a mix of salmonberry, small fruited bulrush, and some
willows. Soils are a mucky loam and soils were saturated during our summer site visit.
Although we did not rate this wetland due to the fact that even the smallest buffer crosses
the existing road, it appears to be a Category 3 wetland which according to Code would
have a minimum buffer of 25’ and a maximum buffer of 50’
Proposed Project
The proposed project is the resurfacing of an existing gravel road to remove blackberry
and weeds and place a 10’ wide gravel access road. The buffer of the wetland, even at
25’ crosses over the existing road. However, according to Chapter 16.10.040.3 of the
City of Auburn Municipal Code, which list exemptions from the Code the following
exemption for maintenance and work on existing utility roads is as follows ;
River Rock
Sewall Wetland Consulting, Inc.
December 5, 2012
Page 10
3. Normal and routine maintenance, operation, repair and reconstruction of existing
roads, streets, utilities and associated structures; provided, that reconstruction of any
structures may not increase the impervious area and may not cause further encroachment
on the critical area or its buffer, and may not result in adverse impacts to surface water
and ground water quality. Operation and maintenance includes vegetation management
performed in accordance with best management practices that is part of ongoing
maintenance of structures, infrastructure, or utilities; provided, that such management
actions are part of regular and ongoing maintenance, do not expand further into the
critical area, are not the result of an expansion of the structure or utility, and do not
directly impact an endangered or threatened species;
It appears the proposed access road falls under this exemption. As such, no impacts to
wetlands or buffers are proposed.
If you have any questions regarding this report, please call us at (253) 859-0515 or at
esewall@sewallwc.com .
Sincerely,
Sewall Wetland Consulting, Inc.
Ed Sewall
Senior Wetlands Ecologist