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HomeMy WebLinkAbout20101006001951 STORM WATER EASEMENT AND MAINTENANCE AGREEMENT 100610 Return Address: City of Auburn City Clerk 25 West Auburn,WA 98001 20101006001951 PACIFIC NW TIT EAS 80.00 PAGE-001 OF 019 10/06/2010 15:29 KING COUNTY, WA Above this line reserved for recording information. 1Ct \ \Lk 2.- STORM WATER EASEMENT AND MAINTENANCE AGREEMENT FAC08-0009 Reference#(if applicable): N/A Grantor/Borrower: FONPEE,LLC Grantee/Assignee/Beneficiary: City of Auburn Legal Description/STR: NE 1/4 S2—T21 N—R4E jt' Assessor's Tax Parcel ID#: 022104-9098 gill' 1S EASEMENT AND AGREEMENT made and entered into this /7 day of L , 2008, by and between the City of Auburn, a municipal corporation of King County, Washington, hereinafter referred to as "CITY" and FONPEE, LLC hereinafter referred to as "PROPERTY OWNER". WHEREAS, PROPERTY OWNER has applied for certain permits with the CITY for the construction of facilities for Omega-Baja Office & Warehouse Development located at 3705 West Valley Highway NW, which create impervious surface; and WHEREAS, the PROPERTY OWNER will complete a storm system; and WHEREAS, the PROPERTY OWNER and the CITY desire that the storm system be maintained to provide adequate facilities for controlling both the quantity and quality of storm drainage; and WHEREAS, for maintenance of a storm system it is necessary to have appropriate right-of-way to bring in equipment to conduct maintenance functions; and WHEREAS, maintenance requirement is a covenant running with the land and binding upon all heirs, successors and assigns of both parties; and rah Storm Water Easement and Maintenance Agreement Page 1 of 19 WHEREAS, the parties desire that this Agreement be recorded to advise heirs, successors and assigns of both parties as to the existence of this easement and agreement; and WHEREAS, an easement is needed to bring in maintenance equipment; and WHEREAS, the parties are both desirous of permitting inspection of the storm system to make certain that it is functioning properly and for purposes of determining the appropriate repairs. NOW, THEREFORE, BASED UPON MUTUAL COVENANTS TO BE DERIVED THE PARTIES AGREE AS FOLLOWS: Section 1, EASEMENT PROPERTY OWNER hereby provides a non-exclusive easement to the City for access, inspection, and maintenance for the purposes of this Agreement and the attached Storm Water Pollution Prevention Plan, over, under and on that real estate described in Exhibit "A" & "B" and on that portion of the property as showing on the approved Record Drawings revised pursuant to construction records for the City of Auburn under Permit No. FAC08-0009, which record drawings are hereby incorporated by reference as if set out in full. This easement shall be a burden to that real estate which is legally described and attached as Exhibit "A" & `B" and incorporated herein by this reference, and shall be a benefit to the City Storm Drainage Utility System. Section 2, HEIRS, SUCCESSORS AND ASSIGNS This Agreement shall be binding upon the heirs, successors and assigns of the parties. Storm Water Easement and Maintenance Agreement Page 2 of 19 Section 3, MAINTENANCE The PROPERTY OWNER agrees to maintain the storm system in accordance with the ordinances and all applicable codes of the CITY and the Storm Water Pollution Prevention Maintenance and Operation Schedule attached as Exhibit "C" and incorporated herein by this reference. The PROPERTY OWNER does hereby agree that the CITY may enter onto the property of the PROPERTY OWNER via the easement described above to inspect and perform necessary maintenance if, after the PROPERTY OWNER is given notice to maintain, the PROPERTY OWNER fails to maintain. Further, the PROPERTY OWNER agrees the CITY may enter onto the property of PROPERTY OWNER via the easement described above to perform emergency maintenance in the event of the storm system's failure which might result in adverse impacts(s) on public facilities or private facilities of other property owners. In both events the PROPERTY OWNER agrees to reimburse the CITY for the costs incurred by the CITY in maintaining the storm system. Should the CITY incur attorney's fees and/or costs in enforcing the agreement and/or in maintaining or collecting maintenance fees, the PROPERTY OWNER agrees to pay reasonable attorney's fees and all costs incurred by the CITY. Section 4,ACKNOWLEDGMENT OF OTHER ENFORCEMENT ACTIONS PROPERTY OWNER acknowledges that there may be liability for violations of codes that could result in additional fines and/or the possibility of incarceration in addition to the fees for maintenance should violations occur. Storm Water Easement and Maintenance Agreement Page 3 of 19 EXECUTED as of the date first written above. ea. , % G thorized Signature D e Authorized Signature Date STATE OF WASHINGTON) ) ss COUNTY OF KING ) I certify I have know or have satisfactory evidence that 111 id-loet P . Cutiec, git are the person(s) who appeared before me, an. :id person(s, acknowledged that Oahe/they he/they signed this instrument on oath stated ' i . she/,,-y ,f/were authorized to exec to e instrument and acknowledge as the;.r_/.�: y of a limited liability company, to be the ree a voluntary act of such party for the uses and purposes mentioned in the instrument. Dated ®, `v AN+ fie 4 'f ir ',AA '\ A • t L� , Notary Public in and for the State of WashingN 4BZ ., .:a Residing at ILit ICUr(\ ' f n \P1:4, 05 �r ;,.4 My appointment expires '1 a a0 is ww.s.M:0 Storm Water Easement and Maintenance Agreement Page 4 of 19 CITY OF AUBURN min Carlaw Drainage g Engineer Draina En ineer Dade STATE OF WASHINGTON ) )ss. County of King ) I certify that I know or have satisfactory evidence that Tim Carlaw is the person who appeared before me, and said person acknowledged that he signed this instrument, on oath stated that he was authorized to execute the instrument and acknowledged it as the STORM DRAINAGE ENGINEER of THE CITY OF AUBURN to be the free and voluntary act of such party for the uses and purposes mentioned in this instrument. Dated /O/fie ..... ....,, �i 0 SO1r4� '',�� 1 zz� I- c.6. CT y Ili • , = Notary Pu • in and for the State Washington a. 7A-1 VI/0G i Residing at I v 1 ci ,,�• 9_1�, 0 ` My appointment expires //l t q/r i deli S Ott HS/t1b File: 1209 REF. H\Development\Projects\Omega-Baja\Legal Documents\2008 Storm Water Easement and Maintenance Agreement Page 5 of 19 EXHIBIT `A' OMEGA-BAJA INDUSTRIAL CONTRACTORS 3705 WEST VALLEY HIGHWAY NW AUBURN, WA 98001 Tax Parcel No. 0221049098 LEGAL DESCRIPTION THAT PORTION OF GOVERNMENT LOT 1 AND THE SOUTHEAST QUARTER OF THE NORTHEAST QUARTER OF SECTION 2,TOWNSHIP 21 NORTH,RANGE 4 EAST,WILLAMETTE MERIDIAN,IN KING COUNTY,WASHINGTON,DESCRIBED AS FOLLOWS: COMMENCING ON THE EAST LINE OF SAID GOVERNMENT LOT 1 AT A POINT WHICH IS SOUTH 01°33'33"WEST,945.12 FEET FROM THE NORTHEAST CORNER THEREOF; THENCE NORTH 89° 17'33"WEST,428.00 FEET; THENCE NORTH 01°33'33" EAST, 99.91 FEET TO A POINT ON THE SOUTH LINE OF THE NORTH 845.12 FEET OF THE NORTHEAST QUARTER OF SAID SECTION 2; THENCE NORTH 89° 17'33"WEST,ALONG SAID SOUTH LINE, 652.19 FEET TO A POINT ON THE EAST LINE OF THE WEST 1,524.60 FEET OF THE NORTHEAST QUARTER OF SAID SECTION 2; THENCE SOUTH 01° 05'07"WEST ALONG SAID EAST LINE,317.86 FEET TO A POINT ON THE NORTH LINE OF THE SOUTH 1,236.00 FEET OF THE NORTHEAST QUARTER OF SAID SECTION 2; THENCE SOUTH 89°55'04"EAST ALONG SAID NORTH LINE,309.58 FEET TO A POINT ON THE NORTHERLY LINE OF THE M.MARKDAHL ROAD,AS CONVEYED TO KING COUNTY BY DEED RECORDED IN VOLUME 1167 OF DEEDS, PAGE 133, RECORDING NUMBER 1592515(ALSO KNOWN AS MEREDITH ROAD OR S.292ND STREET); THENCE NORTHEASTERLY ALONG SAID NORTHERLY LINE TO THE EAST LINE OF THE NORTHEAST QUARTER OF SAID SECTION 2; THENCE NORTH ALONG SAID EAST LINE 95.00 FEET,MORE OR LESS,TO THE POINT OF BEGINNING; EXCEPT THE RIGHT OF WAY OF SECONDARY STATE HIGHWAY NO.5M(WEST VALLEY HIGHWAY);AND EXCEPT THAT PORTION THEREOF CONVEYED TO THE CITY OF AUBURN BY DEED RECORDED UNDER RECORDING NUMBER 9604220946. 0. WA tae°t=2 o o� • ` � s 00 • \ • ee4P, 32506�(, .0 -0° .0..a uo°° NAL LAS ' NNN • EXPIRES /1•31.07 1' t, AO' Storm Water Easement and Maintenance Agreement Page 6 of 19 EXHIBIT `B' IIYIH3I1:1Y IYdI3NIHd) AMH A3T1YA 193M Cr) as - f o ,_I t I— 1 1 I � �t w V U f`_�j ' :t } t CZ I I .1 , Z+ v o ; I It E- w Z C:6� y (7)Z : a O Q 2 :i; Z V CC 4 t vV W rn P p 1 Nu Z Z u_¢ >- U t � • .1 CD t- .� t � ~ Q C' N t -..." __I Q 1 i.-.t m If) �. — LIJ _ 1 N rZI. T� II CX _ — — as t � B i Vl 671;.'W',. t g N /\ �' Q Ci7 p o t C A Q z 0 0 z L- N a • ..� tt W o cUn ZCC r� lii op I \ t m CV Q iii a 1- /. i cn 0 W lU � t C/) r'` Q Q Z a_Mo th , I 1 "(A a. by 1 CD 1 1 t Q W i i z ' m ii I o • ; • \`\ -Ili ad II :I I \` 111 / \ W Z � 2 i i . I o J , I IL 1 Storm Water Easement and Maintenance Agreement Page 7 of 19 EXHIBIT `C' STORM WATER POLLUTION PREVENTION MAINTENANCE and OPERATION SCHEDULE for OMEGA-BAJA GARAGE & OFFICE, PHASE 1 SEPA NO. 07-0017 FAC NO. 08-0009 GRA NO. 07-0013 Site Address: The project is located in NE QTR of Section2, Township 21N Range 4 East, W.M., 3705 West Valley Highway NW, Auburn, WA 98001. The tax parcel number is 0221049098. Introduction: This storm drainage technical information report has been prepared to address the City of Auburn's site development and storm drainage requirements for the proposed Omega-Baja Garage & Office, Phase 1 located at 3705 West Valley Highway NW, Auburn, WA 98001 . The site has an area of approximately 6.25 acres and is currently being used by Omega-Baja Industrial Contractors under a temporary use permit from the City. An old house on the property has been converted into a temporary office for this purpose. The east end of the site has been cleared, but is undeveloped. The west end of the site is wooded and undeveloped. The subject site will be (developed as the headquarters of Omega-Baja Industrial Contractors, and will contain an office building, a garage for vehicle maintenance, and a storage shed. The subject site has a temporary entrance off of South 292nd Street (37th Street NW). The only existing building is an old house that is being used as temporary office space by Omega-Baja Industrial Contractors. It has well water and a septic tank. All existing development will be demolished or abandoned upon completion of Phase 1 construction. Storm Water Easement and Maintenance Agreement Page 8 of 19 According to the City of Auburn's Construction Standards for storm water management, the city requires storm water quantity and quality control to all proposed developments. We have proposed to collect all of the storm water runoff from the landscaped, building and pavement areas in a series of catch basins. This water will be conveyed by storm drainage pipe to a storm water vault that will provide both storm water detention and water quality treatment, located on the eastern portion of the site. Here the storm water will be released into a 24" diameter proposed storm drainage line running to a new catch basin on West Valley Highway at the northeast corner of the site. From there, the storm water will be conveyed in a 30" diameter pipe (to be a new part of the public system) northward along the west side of West Valley Highway to an existing catch basin adjacent to the Span Alaska office buildings. Plan Goal: The specific purpose for the storm water facility is to minimize pollution that is typically associated with modern development. In general, pollution from motor vehicles and pollution generated from erosion. Attached to this narrative is a maintenance manual, which offers guidelines to the owner for storm water facility maintenance. Prevention BMP'S: The catch basins shall have stenciled on them "DUMP NO WASTE — DRAINS TO STREAM." The owner shall be responsible for sweeping the lot, installing storm drainage stenciling and provide spill control procedures. In case of spill call DOE at 1-425-649-7000. The catch basins, detention/wetpond, and control structures will be visually inspected for accumulation of debris and silt and will be maintained as required by this pollution prevention plan and attachments. • Maintenance Standards for Drainage Facilities (from the Department of Ecology Storm Water Manual, August 2001) No. 3 — Closed Detention Systems (Tanks/Vaults) No. 4 — Control Structure/Flow Restrictor No. 5 — Catch Basins No. 8 — Typical Biofiltration Swale No. 12 — Wetvaults Storm Water Easement and Maintenance Agreement Page 9 of 19 Treatment BMP'S: A wet vault has been installed to treat runoff for conventional pollutants. The wet vault was designed to treat 64% of the 2-year storm event (water quality storm) for water quality treatment. In addition, the detention pond was designed to detain the volume created from releasing half the existing 2-year, 10, 25, and 100-year storm events, while holding the developed 2- year, 10, 25, and 100-year storm volumes. The City of Auburn Storm Drainage Utility section is to review and approve any changes to this Storm Water Pollution Prevention Plan prior to changes in its implementation. Additionally, any changes in ownership or person of responsibility are to be reported to the City of Auburn Storm Drainage Utility section. Inspection/Maintenance: Regular inspections of the drainage facilities should be carried out twice per year, in the spring and fall. The responsible party should keep records of these inspections available for review by the City. Additional inspections may be required after severe storms. Routine maintenance of the site will include mowing, care of landscaping and the removal of trash and debris from the drainage system. The parking lots and driveways should be kept clean and in repair. Events such as major storms or heavy winds will require immediate inspections for damages. To ensure proper water quality and treatment, the wet vault must be properly maintained. Be careful to avoid introducing landscape fertilizer to receiving waters or groundwater. If wetpond side slopes become eroded over 2" deep, stabilize by using appropriate erosion control measures (e.g., rock reinforcement, planting of grass, compaction). Catch basins shall be cleaned when sump is 1/3' full of sediment or debris. Person of Responsibility: Mike Cotter Omega-Baja Industrial Contractors 3705 West Valley Highway NW Auburn, WA 98001 Tel: (253) 804-6000 Storm Water Easement and Maintenance Agreement Page 10 of 19 Design Engineer: Barry Knight, P.E. CTS Engineers 1412 — 112th Avenue NE, Suite 102 Bellevue, WA 98004 Tel: (425) 455-7622 Plan and/or Information Updates: The City of Auburn Storm Drainage Utility section is to review and approve any changes to this Storm Water Pollution Prevention Plan prior to changes in its implementation. Additionally, any changes in ownership or person of responsibility are to be reported to the City Storm Drainage Utility section. INSPECTION/MAINTENANCE CHECKLIST ° Y' iiiiti air � i = t, � � V g i STRUCTURE D � # 5 a`�Yh e 'fa, Results/ Maintenance Date Inspection All Catch Basins Results Maintenance Done Storm Detention/ Inspection Wet Vault Results Maintenance Done Inspection Conveyance Pipes Results Maintenance Done Flow Control Inspection Structure Results Maintenance Done Biofiltration Swale Inspection Results Maintenance Done Storm Water Easement and Maintenance Agreement Page 11 of 19 Maintenance Standards for Drainage Facilities: The facility-specific maintenance standards contained in this section are intended to be conditions for determining if maintenance actions are required as identified through inspection. They are not intended to be measures of the facility's required condition at all times between inspections. In other words, exceeding these conditions at any time between inspections and/or maintenance does not automatically constitute a violation of these standards. However, based upon inspection observations, the inspection and maintenance schedules shall be adjusted to minimize the length of time that a facility is in a condition that requires a maintenance action. No. 3—Closed Detention Systems(TanksNaults) Maintenance Defect Conditions When Maintenance is Needed Results Component Expected When Maintenance is Performed, Storage Area Plugged Air Vents One-half of the cross section of a vent is Vents open and blocked at any point or the vent is damaged. functioning. Debris and Sediment Accumulated sediment depth exceeds 10% All sediment and of the diameter of the storage area for 1/2 debris removed length of storage vault or any point depth from storage exceeds 15%of diameter. area. (Example: 72-inch storage tank would require cleaning when sediment reaches depth of 7 inches for more than 1/2 length of tank.) Joints Between Any openings or voids allowing material to All joint between Tank/Pipe Section be transported into facility. tank/pipe sections are sealed. (Will require engineering analysis to determine structural stability). Tank Pipe Bent Out Any part of tank/pipe is bent out of shape Tank/pipe of Shape more than 10%of its design shape. repaired or (Review required by engineer to determine replaced to structural stability). design. Vault Structure Cracks wider than 1/2-inch and any Vault replaced or Includes Cracks in evidence of soil particles entering the repaired to design Wall, Bottom, structure through the cracks, or specifications and Damage to Frame maintenance/inspection personnel is structurally and/or Top Slab determines that the vault is not structurally sound. sound. Cracks wider than 1/2-inch at the joint of No cracks more any inlet/outlet pipe or any evidence of soil than 1/4-inch wide particles entering the vault through the at the joint of the walls. inlet/outlet pipe. Storm Water Easement and Maintenance Agreement Page 12 of 19 No. 3—Closed Detention Systems(Tanks/Vaults) •Maintenance Defect Conditions When Maintenance is Needed Results Component Expected When Maintenance Performed Manhole Cover Not in Place Cover is missing or only partially in place. Manhole is Any open manhole requires maintenance. closed. Locking Mechanism One maintenance person with proper tools Mechanism opens Not Working cannot open mechanism. Bolts into frame with proper tools. have less than 1/2 inch of thread(may not apply to self-locking lids). Cover Difficult to One maintenance person cannot remove lid Cover can be Remove after applying normal lifting pressure. Intent removed and is to keep cover from sealing off access to reinstalled by one maintenance. maintenance person. Ladder Rungs Unsafe Ladder is unsafe due to missing rungs, Ladder meets misalignment, not securely attached to design standards. structure wall, rust, or cracks. Allows maintenance person safe access. Catch Basins See"Catch Basins" See"Catch Basins"(No. 5). See"Catch (No. 5) Basins"(No. 5). No. 4—Control Structure/Flow Restrictor Maintenance Defect Condition When Maintenance is Results Expected Component Needed When Maintenance is Performed General Trash and Debris Material exceeds 25%of sump depth or 1 Control structure (Includes Sediment) foot below orifice plate. orifice is not blocked. All trash and debris removed. Structural Damage Structure is not securely attached to Structure securely manhole wall. attached to wall and outlet pipe. Structure is not in upright position (allow Structure in correct up to 10%from plumb). position. Connections to outlet pipe are not Connections to watertight and show signs of rust. outlet pipe are watertight;structure repaired or replaced and works as designed. Any holes, other than designed holes, in Structure has no the structure. holes other than designed holes. Storm Water Easement and Maintenance Agreement Page 13 of 19 No. 4—Control Structure/Flow Restrictor Maintenance Defect Condition When Maintenance is Results Expected Component Needed Wit Maintenance Is PertmIrted Cleanout Gate Damaged or Missing Cleanout gate is not watertight or is Gate is watertight missing. and works as designed. One maintenance person cannot move Gate moves up and up and down gate. down easily and is watertight. Chain/rod leading to gate is missing or Chain is in place damaged. and works as designed. Gate is rusted over 50%of its surface Gate is repaired or area. replaced to meet design standards. Orifice Plate Damaged or Missing Control device is not working properly Plate is in place and due to missing, out of place, or bent works as designed. orifice plate. Obstructions Any trash, debris, sediment, or vegetation Plate is free of all blocking the plate. obstructions and works as designed. Overflow Pipe Obstructions Any trash or debris blocking(or having Pipe is free of all the potential of blocking)the overflow obstructions and pipe. works as designed. Manhole See"Closed See"Closed Detention Systems"(No. 3). See"Closed Detention Systems" Detention Systems" (No. 3). (No. 3). Catch Basin See"Catch Basins" See"Catch Basins"(No. 5). See"Catch Basins" (No. 5). (No. 5). Storm Water Easement and Maintenance Agreement Page 14 of 19 No. 5—Catch Basins Maintenance Defect Conditions When Maintenance Is Needed Results Expected, Component When Maintenance is performed General Trash& Trash or debris which is located immediately No Trash or debris Debris in front of the catch basin opening or is located immediately in blocking inletting capacity of the basin by front of catch basin or on more than 10%. grate opening. Trash or debris(in the basin)that exceeds 60 No trash or debris in the percent of the sump depth as measured from catch basin. the bottom of basin to invert of the lowest pipe into or out of the basin, but in no case less than a minimum of six inches clearance from the debris surface to the invert of the lowest pipe. Trash or debris in any inlet or outlet pipe Inlet and outlet pipes blocking more than 1/3 of its height. free of trash or debris. Dead animals or vegetation that could No dead animals or generate odors that could cause complaints or vegetation present within dangerous gases(e.g., methane). the catch basin. Sediment Sediment(in the basin)that exceeds 60 No sediment in the catch percent of the sump depth as measured from basin. the bottom of basin to invert of the lowest pipe into or out of the basin, but in no case less than a minimum of 6 inches clearance from the sediment surface to the invert of the lowest pipe. Structure Top slab has holes larger than 2 square Top slab is free of holes Damage to inches or cracks wider than 1/4 inch. and cracks. Frame and/or Top Slab (Intent is to make sure no material is running into basin). Frame not sitting flush on top slab, i.e., Frame is sitting flush on separations of more than 3/4 inch of the frame the riser rings or top slab from the top slab. Frame not securely and firmly attached. attached Fractures or Maintenance person judges that structure is Basin replaced or Cracks in unsound. repaired to design Basin Walls/ standards. Bottom Grout fillet has separated or cracked wider Pipe is regrouted and than 1/2 inch and longer than 1 foot at the joint secure at basin wall. of any inlet/outlet pipe or any evidence of soil particles entering catch basin through cracks. Settlement! If failure of basin has created a safety, Basin replaced or Misalignment function, or design problem. repaired to design standards. Vegetation Vegetation growing across and blocking more No vegetation blocking than 10%of the basin opening. opening to basin. Storm Water Easement and Maintenance Agreement Page 15 of 19 No. 5—Catch Basins Maintenance Defect Conditions When Maintenance is Needed Results Expected Component ;WherrMisdrdenance is performed Vegetation growing in inlet/outlet pipe joints No vegetation or root that is more than six inches tall and less than growth present. six inches apart. Contamination See"Detention Ponds" (No. 1). No pollution present. and Pollution Catch Basin Cover Not in Cover is missing or only partially in place. Any Catch basin cover is Cover Place open catch basin requires maintenance. closed. Locking Mechanism cannot be opened by one Mechanism opens with Mechanism maintenance person with proper tools. Bolts proper tools. Not Working into frame have less than 1/2 inch of thread. Cover Difficult One maintenance person cannot remove lid One maintenance person to Remove after applying normal lifting pressure. can remove cover. (Intent is keep cover from sealing off access to maintenance.) Ladder Ladder Rungs Ladder is unsafe due to missing rungs, not Ladder meets design Unsafe securely attached to basin wall, misalignment, standards and allows rust,cracks, or sharp edges. maintenance person safe access. Metal Grates Grate opening Grate with opening wider than 7/8 inch. Grate opening meets (If Applicable) Unsafe design standards. Trash and Trash and debris that is blocking more than Grate free of trash and Debris 20%of grate surface inletting capacity. debris. Damaged or Grate missing or broken member(s)of the Grate is in place and Missing. grate. meets design standards. Storm Water Easement and Maintenance Agreement Page 16 of 19 No. 8—Typical Biofiltration Swale Maintenance Defect or Condition When Recommended Maintenance to Component Problem Maintenance is Needed Correct Problem General Sediment Sediment depth exceeds 2 Remove sediment deposits on grass Accumulation on inches. treatment area of the bio-swale. Grass When finished, swale should be level from side to side and drain freely toward outlet. There should be no areas of standing water once inflow has ceased. Standing Water When water stands in the Any of the following may apply: swale between storms and remove sediment or trash blockages, does not drain freely. improve grade from head to foot of swale, remove clogged check dams, add underdrains or convert to a wet biofiltration swale. Flow spreader Flow spreaders uneven or Level the spreader and clean so that clogged so that flows are not flows are spread evenly over entire uniformly distributed through swale width. entire swale width. Constant When small quantities of Add a low-flow pea-gravel drain the Baseflow water continually flow through length of the swale or by-pass the the swale, even when it has base flow around the swale. been dry for weeks, and an eroded, muddy channel has formed in the swale bottom. Poor Vegetation When grass is sparse or bare Determine why grass growth is poor Coverage or eroded patches occur in and correct that condition. Re-plant more than 10%of the swale with plugs of grass from the upper bottom. slope: plant in the swale bottom at 8- inch intervals. Or re-seed into loosened, fertile soil. Vegetation When the grass becomes Mow vegetation or remove nuisance excessively tall (greater than vegetation so that flow not impeded. 10-inches);when nuisance Grass should be mowed to a height of weeds and other vegetation 3 to 4 inches. Remove grass start to take over. clippings. Excessive Grass growth is poor If possible,trim back over-hanging Shading because sunlight does not limbs and remove brushy vegetation reach swale. on adjacent slopes. Inlet/Outlet Inlet/outlet areas clogged Remove material so that there is no with sediment and/or debris. clogging or blockage in the inlet and outlet area. Trash and Trash and debris Remove trash and debris from Debris accumulated in the bio-swale. bioswale. Accumulation Storm Water Easement and Maintenance Agreement Page 17 of 19 No. 8—Typical Biofiltration Swale Maintenance Defect or Condition When Recommended Maintenance to Component Problem Maintenance is Needed Correct Problem Erosion/Scouring Eroded or scoured swale For ruts or bare areas less than 12 bottom due to flow inches wide, repair the damaged area channelization, or higher by filling with crushed gravel. If bare flows. areas are large, generally greater than 12 inches wide, the swale should be re-graded and re-seeded. For smaller bare areas, overseed when bare spots are evident, or take plugs of grass from the upper slope and plant in the swale bottom at 8-inch intervals. Storm Water Easement and Maintenance Agreement Page 18 of 19 No. 12—Wetvaults Maintenance Detect Condition When Maintenance Results Expected When Component is Needed Maintenance is Performed General Trash/Debris Trash and debris accumulated Remove trash and debris from Accumulation in vault, pipe or inlet/outlet vault. (includes floatables and non- floatables). Sediment Sediment accumulation in vault Remove sediment from vault. Accumulation in bottom exceeds the depth of Vault the sediment zone plus 6- inches. Damaged Pipes Inlet/outlet piping damaged or Pipe repaired and/or replaced. broken and in need of repair. Access Cover Cover cannot be opened or Pipe repaired or replaced to Damaged/Not removed, especially by one proper working specifications. Working person. Ventilation Ventilation area blocked or Blocking material removed or plugged. cleared from ventilation area. A specified%of the vault surface area must provide ventilation to the vault interior(see design specifications). Vault Structure Maintenance/inspection Vault replaced or repairs made so Damage- personnel determine that the that vault meets design Includes Cracks vault is not structurally sound. specifications and is structurally in Walls Bottom, sound. Damage to Frame and/or Top Slab Cracks wider than 1/2-inch at Vault repaired so that no cracks the joint of any inlet/outlet pipe exist wider than 1/4-inch at the or evidence of soil particles joint of the inlet/outlet pipe. entering through the cracks. Baffles Baffles corroding, cracking, Baffles repaired or replaced to warping and/or showing signs specifications. of failure as determined by maintenance/inspection staff. Access Ladder Ladder is corroded or Ladder replaced or repaired to Damage deteriorated, not functioning specifications, and is safe to use properly, not attached to as determined by inspection structure wall, missing rungs, personnel. Replace sign warning has cracks and/or misaligned. of confined space entry Confined space warning sign requirements. Ladder and entry missing. notification complies with OSHA standards. Storm Water Easement and Maintenance Agreement Page 19 of 19