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Operation and Maintenance Plan 08-16-07 001SAMANTHA RIDGE Prepared for: Prepared by: Operation & Maintenance Plan Jack Long The One Eleven Building Auburn, WA 98002 (253)846-5756 August 14, 2007 Pete Swan ~:,,'; . ~t ~,: ~P\~,~F Qi~ P~G~6 Reviewed by: Jeff McInnis, PE PETRA ENGINEERING, LLC 535 Dock Street, Ste 213 Tacoma, WA 98402 (253)752-7617 Project No: 06-036 Project Name: SAMANTHA RIDGE Oper & Main -Samantha Ridge (08.14.07).doc ~' ~ E it; GII~BERING, LLC 535000X 3TREEr•9URE 219 ITACOMA I WAI B9d021 PHONE 126.9)]52-]61] I FAX 1269)]61-6562 1 NNJW.PETnAENG.NET TABLE OF CONTENTS I. STORMWATER FACILITY MAINTENANCE GUIDE 3 INTRODUCTION 3 What is Stormwater Runoff? 3 What is a Storm Drainage System and how does it work? 3 What does Stormwater Runoff have to do with Water Quality 3 Your Stormwater Facility 3 Who is Responsible for Maintaning Stormwater Facilities 3 How [o Use the Stormwater Facility Maintenance Guide 4 Included in This Guide q A Regional Approach to Stormwater Management 4 YOUR STORMWATER FACILITIES 4 FACILITY KEY 4 SITE PLAN 5 QUICK LIST 6 MAINTENANCE CHECKLISTS 7 Detention Pond Checklist 6 Control Structure Checklist 11 Catch Basin Checklist 13 Vortechs Model 2000 Checklist i6 Fencing/Shrubbery ScreenlOther Landscaping Checklist 17 Grounds and Landscape Checklist 18 Drywells, French Drains, and Downspout Checklist 19 RESOURCE LISTING 2p GLOSSARY 22 ~~o.;_ oara% ancez I. STORMWATER FACILITY MAINTENANCE GUIDE INTRODUCTION What is Stormwater Runoff? When urban and suburhan development covers the land with buildings, streets and parking lots, much of the native topsoil, duff, trees, shrubs and grass are replaced by asphalt and concrete. Rainfall that would have soaked directly into the ground instead stays on the surtace as Stormwater runoff making its way into storm drains (including man-made pipes, ditches, or Swale networks), Stormwater ponds, surtace and groundwater, and eventually to Puget Sound. What is a Storm Drain System and how does it work? The storm drain system for most developments includes measures to carry, store, cleanse, and release the Stormwater. Components work together to reduce the impacts of development on the environment. Impacts can include flooding which results in property damage and blocked emergency routes, erosion which can cause damage to salmon spawning habitat, and pollution which harms fsh andlor drinking water supplies. The storm drain system provides a safe method to carry Stormwater to the treatment and storage area. Swales and ponds filter pollutants from the Stormwater by physically settling out particles, chemically binding pollutants to pond sediments, and biologically converting pollutants to less harmful compounds. Ponds also store treated water, releasing it gradually to a nearby stream or to groundwater. What does Stormwater Runoff have to do with Water Quality? Stormwater runoff must be treated because it carries litter, oil, gasoline, fertilizers, pesticides, pet wastes, sediments, and anything else that can float, dissolve or be swept along by moving water. Left untreated, polluted Stormwater can reach nearby waterways where it can harm and even kill aquatic life. It can also pollute groundwater to the extent that it requires treatment before it is suitable for drinking. Nationally, stormwaler is recognized as a major threat to water quality. Remember to keep everything out of stormwaler systems except the rainwater they are designed to collect. Your Stormwater Facility Different types of ponds are designed for different purposes. For example, wet ponds primarily provide treatment of Stormwater. Dry ponds or infiltration ponds are designed [o provide storage for stormwaler and allow for its gradual release downstream or into the ground. The private stormwaler facility for this project includes a water quality LCF vault, a stormwaler retention vault, and a conveyance system to collect site runoff from roadways, driveways, and roofs. Who is Responsible for Maintaining Stormwater Facilities? All Stormwater facilities require maintenance. Regular maintenance ensures proper functioning and preserves visual appeal. This Stormwater Facility Maintenance Guide was designed to explain how stormwaler facilities work and provide user-friendly, straightforward guidance on facility maintenance. You are responsible for regularly maintaining privately owned ponds, catch basins, pipes and other drainage facilities on your property. Stormwater facilities located in public rights-of-way are maintained by local governments. The private Stormwater facilities on this site will be maintained by a homeowner's association. ~~..-r- „,,~,;= o~. ,., ~, How to Use the stormwater Facility Maintenance Guide This Maintenance Guide includes a Site Plan specific to your development and a Facility Key that identifies the private stormwater facilities you are responsible for maintaining. A "Quick List" of maintenance activities has also been included to help you identify the more routine needs of your facility. Included in This Guide ^ Comprehensive Maintenance Checklists that provide specific details on required maintenance ^ Pollution Prevention Tips that list ways to protect water quality and keep storm drain systems functioning smoothly ^ Resources to provide more information and technical assistance A Regional Approach to stormwater Management It is important to educate and involve area residents in water quality issues and stormwater management. stormwater runoff is a widespread cause of water quality impairment and stream degradation. The jurisdictions should work together with residents, businesses, community groups and schools to address this problem. This guide focuses on providing information in ways [hat you can reduce stormwater impacts through pollution prevention and proper facility maintenance. YOUR STORMWATER FACILITIES This section consists of two parts that are to be used together: the Facility Key and the Site Plan. Review the site plan and identify the numbers denoting a feature of the system. Then check the facility key for the feature type and checklist name. FACILIN KEY The stormwater facility in your neighborhood is comprised of the following elements: Type of Feature & Checklist Name Location on Site Plan Detention Pond 1 Control Structure 2 Catch Basins 3 Vortechs Mode1200 q FencinglShrubbery ScreenlOther Landscaping 5 Grounds and Landscape 6 Drywells, French Drains, or Downspouts See individual lot site plan. 'THE MAINTENANCE FOR THE VORTECHS MODEL 2000 IS AS REQUIRED BY THE MANUFACTURER. IT IS ANTICIPATED AND RECOMMENDED THAT THE HOME OWNER ASSOCIATION SIGN UP FOR REGULAR MAINTENANCE FROM THE PROVIDER OF THIS SYSTEM. SITE PLAN FH~~~ QUICK LIST The following is an abbreviated checklist of the most common types of maintenance required. Please go over this checklist after heavy rains. The list represents minimum maintenance to be performed and should be completed in conjunction with the other checklists for an effective maintenance program. O Inspect catch basin grates to see that they are not clogged or broken. Remove twigs, leaves, or other blockages. Contact the local jurisdiction to replace [he grate if it is broken. O Inspect inlet and outlet pipes for blockages. Clear all blockages. O Inspect filter strip, swale and pond walls for erosion or caved in areas. O Inspect riprap (rocks) at the inlets and outlets of culverts and other pipes. If they are silted in or eroded away, replace [hem. MAINTENANCE CHECKLISTS The Maintenance Checklists in this packet are for your use when inspecting the stormwater facilities on your property. This packet has been customized so that only the checklists for your facilifies are included. If you feel you are missing a checklist, or you have additional facilities not identified or addressed in this packet, please contact your local jurisdiction. The checklists are in tabular format for ease of use. Each describes the area to inspect, inspection frequency, what to look for, and what action to take. A log sheet is included toward the end of the chapter to help you [rack maintenance of your storm drainage system. Although it is not intended for the maintenance survey to involve anything too diffcult or strenuous, there are a few tools that will make the job easier and safer including: ^ Aflashlight ^ Along pole or broom handle ^ Some kind of pry bar or lifting tool for pulling manhole and grate covers ^ Gloves A resource list is included in the next chapter. Here you will fnd the phone numbers of the agencies referred to in the tables, as well as the contractors and consultants who designed and constructed your (acilities. SAFETY WARNING: In keeping with OSHA regulations, you should never stick your head or any part of your body into a manhole or other type of confined space. When looking into a manhole or catch basin, stand above it and use the flashlight to help you see. Use a long pole or broom handle to check sediment depths in confned spaces. NO PART OF YOUR BODY SHOULD BREAK THE PLANE OF THE OPEN HOLE. ?tc[ ,. ~.,.~7 ,~_~ s Detention Ponds Checklist Date Drainage Condition Contlition Frequent System Problem sto sThat y Feature Orc Ob OLa Ou Check For S~isd Any [rash antl debris which exceetl 5 cubic feet per 1,000 square feet (this is about equal to the amount of trash it wnuM take to fJl up one stantlard M 5 Geneal Trash 8 Debris size garbage can). In Trash antl tlebris , general, there should clearetl from site. be no visual evidence of dumping. If less than thresholtl all trash antl debris will be removed as part of next scheduletl maintenance. Any poisonous or No danger of nuisance vegetation poisonous vegetation which may constitute a where maintenance hazard to maintenance personnel or the public personnel or the might normally be. A General Poisonous Vegetation public. Any evidence (Coortlinate with local weetl board) Complete antl noxious weeds of noxious weetls as eratlication of noxious tle(ned by Stale or weetls may not be local regulations. possible. Compliance (Apply requirements of with State or local adopted IPM policies eradication policies for the use of required herbicides . No conaminants or Any evitlence of oil, pollutants present. M S General Contaminants antl gasoline, (Coordinate , Pollution contaminants or other removal/cleanup with pollutants local water quality response agency). Rotlen[s destroyetl Any evidence of antl dam or berth rotlent holes if facility repaired. (Coordinate s acting as a tlam or with local health M General Rotlenl Holes berm, or any evitlence depadment: of water piping coordinate with through dam or berm Ecology Dam Safety via rotlent holes. ORCe if pond exceetls 10 acre-feet. Faciliy is relumetl to design function. Dam results in change (Coortlinate trapping M General Beaver Dams or function of the of beavers antl facility. removal of tlams with appropriate permitting agencies) When insecLS such as Insects tlestroyed or A General Insects wasps antl homers removetl from site. APPly insecticttles in intertere vnth Compliance with maintenance activities. adoptetl IPM policies- '.hTHA R.,.'L ._- ~- Tree growth does not allow maintenance Trees tlo not hinder access or interferes maintenance activities. Tree Growth antl with maintenance Harvestetl trees A General Hazard Trees activity (i.e., slope shoultl be recyGed mowing, silt removal, into mulch or other vactoring, or beneficial uses (e.g., equipment alders for firewood). movements . If If tlead diseased or tlying bees are itlentified (Use a A General cedifietl Arborist to Remove hazard Trees determine health of tree or remOVa regnlrements) Erotletl damage over Slopes shoultl be 2 inches deep where stabilizetl using cause of damage is appropriate erosion M Side Slopes of Pontl Erosion still present or where control measure(s); there is potential for e.g., rock continued erosion reinforcement, planting . of grass, compaction. If erosion is occumng on Any erosion observed on a compacfetl berms a licensetl M,S Side Slopes of Pond compactetl berm civil engineer shoultl be embankment consulted to resolve source of erosion. Accumulated sediment that ezceeds 16% ' ' Sediment Geaned out (typically 6 to 12 ) of the designed pontl to tlesignetl pontl M Storage Area Sediment depth unless shape antl tlep0; otherwise speGfied or pontl reseetletl if affects inleuing or necessary to control outleNng cgndition of erosion. _ the facili . Liner Is visible and has Liner repaired or M Storage Area Gner (If Applicable) more than three l/4- replaced Liner is fully inch holes in it. wveretl. Any part of berm which has settled 4 inches lower than the tlesign elevation. if settlement is apparent, measure berm [o tletermine amount of A Pontl Berms (Dikes) Settlements settlement. Settling Dike is built back to can be an intlication of the tlesign elevation. more severe problems with the berth or outlet works. A licensed Gvil engineer shoultl be consulted to tletermine the source of the settlement. Discernable water flow through pond berm. Ongoing erasion with potential for erosion to continue. Piping eliminatetl. A Pontl Berms (Dikes) Piping (Recommend a Erosion potential Goetechnical engineer resolved. be wlletl in to inspect antl evaluate condition and recommentl repair of wntlition. Trees should be removed. If root Tree growth on system is small (base emergency spillways less than 4 inches) the creates bOCkage root system may be A Emergency Overilowl Tree Growth Problems antl may left in place. Otherwise the roots should be Spillway cause failure of the berm tlue to removetl and the berm unwn(rolletl restored. Alicensetl overtopping. civil engineer should be consultetl far proper berm/spillway restoration. Only one layer of rock exisks above native soil in area fve spuare Emergency Overflow) Emergency Overflow/ feet or larger, or any Rocks antl patl tlep(h A Spillway Spillway exposure of naive soil are restoretl to design at [he top of out Oaw standartls. path of spillway. (Rip- ap on inside slopes neetl not be replacetl.) (M) Monthly from November through April. (A) Once in late summer (preferably September) (S) After any major storm (use 1-inch in 24 hours as a guideline). .._ _..Tr:<: ~loc_ Control Structure/Flow Restrictor Checklist Dale Frequent Drainage Contli[ion Contlition sThal y System Problem sto S d Feature Oxq O~ CtF ~~ Check For EZist Material exceeds Control structure M General Trash and Debris 25% of sump depth orifice is not (Includes Sediment) or 1 foot below blocked. All trash orifice plate. and debris removed. Structure is not Structure securely A General Structural Damage securely attached to attached to wall and manhole wall. outlet pipe. Structure is not in A General Structural Damage upright position Structure in correct (allow up to l0% position. from plumb . Connections to Connections to outlet pipe are water A General Stmctural Damage outlet pipe are not light; structure watertight and show repairetl or replaced signs of rust. and works as desi ned. Any holes-other than designed Structure has no A General Structural Damage holes-in the holes other than structure. designed holes. Damaged or Cleanout gate is not Gale is watertight A Cleanout Gate Missing watertight or is and works as missin desi ned. Gale cannot be Damaged or moved up and down Gate moves up and A Cleanout Gale Missing by one maintenance down easily and is watertight. erson. Damaged or Chain/rod leading to Chain is in place A Cleanout Gale Missing gate is missing or antl works as dama ed. tlesi ned. Damagetl or Gate is msled over Gate is repairetl or A Cleanout Gate Missing 50 % of its surface replaced to meet area. tlesign standartls. Control device is A Odfce Plate Damaged or not working properly due to missing, out Plate is in place antl. Missing of place, or bent works as designed. odfce late. Any trash, debris, sediment or plate is free of all M,5 Orifce Plate Obstructions , obstructions and vegetation blocking the late. works as designed. Any trash or tlebrls blacking (or having Pipe is free of all OverFlOw Pipe Obstructions the potential of obstructions and blocking) the works as designed. overflow i e. Cover is missing or only partially in A Manhole Cover Not in Place place. Any open Manhole is closed. manhole requires maintenance. Mechanism cannot 6e opened by one maintenance person with proper A Manhole Locking Mechanism tools. Bolts into Mechanism opens Not Working frame have less with proper tools. than 1/2 inch of thread (may not apply to self-locking litls . One maintenance person cannot remove lid after Cover can be Cover Diffcult to lying normal removed and A Manhole Remove liftin 9 Pressure. reinstalled by one Intent is to keep maintenance coverfrom sealing person. off access to maintenance. Ladder is unsafe due to missing Ladder meets A Manhole Ladder Rungs mngs, misalignment not design slandartls. Unsafe , securely attached to Allows maintenance slrudure wall, rust, person safe access. or cracks. Key: (M) Monthly from November through April. (A) Once in late summer (preferably September) (S) After any major storm (use 1-inch in 24 hours as a guideline). a ~ ,,, n..,.,~ ... ~ ... .~ Catch Basins Checklist FREpUENCY DRAINAGE SYSTEM DATE PROBLEM CONDITIONS TO CHECK CONDITIONS THAT SHOULD FEATURE FOR EXIST A General "Dump no Stencil or stamp shoultl be Warning signs (e g., "Dump No pollutants" visible antl easily read. Waste-0rains to Stream') shall Stencil or be paintetl or embossetl on or stamp not atljacent to all storm tlrain visible inlets. M,5 General Trash & Trash or tlebris which is No (rash or tlebris locatetl Debris located immetliately in front of immediately in Gont of vetch the catch basin opening or is basin or on grate opening. blacking inletting capacity of the basin b more than 10%. M General Trash & Trash or debris (in the basin) No trash or tlebris in the vetch Debris Ual exceetls 60 percent of the basin. sump tlepth as measuretl from 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. M General Trash & Trash or tlebris in any inlet or Inlet antl outlet pipes free of Debris outlet pipe blocking more Than trash or tlebris. il3 of its height. M General Trash 8 Deatl animals or vegetation No tleatl animals or vegetation Debris That coultl generate odors that present within the catch basin. coultl cause complaints or tlangerous gases (e.g., methane. M General Setllment Setliment (in the basin) that No sediment in the catch exceetls 60 percent of the basin. sump tlepth as measuretl from the bottom o! basin to invert of the lowest pipe into ar out of the basin, but in no rase less than a minimum of 6 inches clearance from the sediment surface m the roved of the lowest ipe. A General SVUCture Top slab has holes larger than Top slab is hee of holes antl Damage to 2 square inches or cracks cracks. frame antllor wider than'/. inch (Intent is to Top Slab make sure no material is running into basin) A General Structure Frame not sitting flush on top Frame is sitting push on the Damage to slab, i.e., separation of more riser rings or top slab and Frame and/or than'/. inch of Ne frame from Flrmly at[achetl. Top Slab the lop slab. Frame not securely attachetl. Catch Basins Checklist Continued) A General Fractures or Maintenance person jutlges Basin replacetl or repairetl to Cocks in that sVUCture is unsound. design stantlartls. Basin Walls/ Bottom A General Factures or Grout fillet has separated ar Pipe is regroutetl and secure Cracks in cracketl wider than'/: inch and at basin wall. Basin Wallsl longer than 1 fool at the joint of Bottom any inleVOUtlet pipe or any evidence of soil particles entering catch basin through tracks. A General Settlement/ If failure of basin has created a Basin replacetl or repaired to Misalignment safety, function, or design design stantlartls. mblem. M General Vegetation Vegetation growing across antl No vegetation blocking blocking more than 1g% of the opening to basin. basino enin . M General Vegetation Vegetation growing in No vegetaton or root growth inleVOUtlel pipe joints that is present. more than six inches tall and less than siz inches apart. M General ConlaminatiD Any evidence of oil, gasoline, No conWminan(s or pollutants n antl wntaminants or other present. Pollution pollutants (Coordinate removal/cleanup with local Watef gUdlty respDOSe a enc . A Catch Basin Cover not in Cover is missing or only Any open catch basin requires Cover place partially in place maintenance. Catch basin cover is Gosetl. A Catch Basin Locking Mechanism cannot be Dpenetl Mechanism opens with proper Cover Mechanism by one maintenance person tools. Not Working with proper tools. Bolls into Name have less than'/, inch of thfeatl. A Catch Basin Cover One maintenance person Cover can be removetl by one Cover DiRCUII to cannot remove litl after maintenance person. Remove applying normal lifting pressure. (Intent is keep cover from sealing off access to maintenance. A Latltler Ladder Latltler is unsafe tlue to Ladtler meets design Rungs missing rungs, not securely standards and allows Unsafe aBachetl to basin wall, maintenance person safe misalignment, rust. cracks, or access. shar etl es. A Grates Grate Grate with opening witler than Grate opening meets tlesign Opening ]/8 inch. stantlartls. Unsafe M,5 Gates Trash 8 Trash and debris that is Grate tree of trash and debds. Debris blocking more than 2g % of grate surface inletting capacity. Ca[ch Basins Checklist (Continued) A Grates Damaged or Grate missing or broken Grate is in place and meets Missing member(s) of the grate. tlesign stantlards. If you are unsure whether a problem exists, please contact a Professional Engineer. Key: (M) Mon[hly from November through April. (A) Once in late summer (preferable September). (S) After any major storm (use 1-inch in 24 hours as a guideline). ~-~,-. ~~.,~_ ,,,..;..r~ - _ .._ _-, Vortechs Stormwater Treatment System Checklist Dare Drainage Contlition Contlition Frequent System i Problem s [o s That y Feature ~~ ~~ (~~ ~~ Check For SExisttl Sediment depth is Sediment within 6" of tlry Accumulated M,S General accumulation weather water sediment should be surtace elevation. removed. Trash and debris accumulated in Trash and debris M,S General Trash and Debris vault, or pipe removed from vault, Accumulation inleUoudet, and inletloutlel floalables and non- piping. Floatables. Oil is extracted from vault using Oil accumulation vac[oring methods. that exceeds 1-inch Coalescing plates M,S General Oil Accumulation at [he water are cleaned by surtace. thoroughly rinsing and flushing. Should be no visible oil de lh on water. Intel ar outlet piping A Structure Damaged Pipes damaged or broken Pipe repaired and or and in need of replaced. re air. Baffles cortoding, cracking, warping and/or showing Baffles repaired or A Structure Baffles signs of failure as replaced to tletermined by specifcations. maintenance/inspec lion ersan. Cracks wider than 1/2-inch or evidence Vault Structure of soil particles Vault replaced or Damage -Includes entering the repairs made so Cracks in Walls structure through that vault meets A Structure , Bottom, Damage to the cracks, or design Frame and/or Top maintenance/inspec specifications and is Slab (ion personnel structurally sountl. determine that the vault is not struclurall sound. Vault Structure Cracks witler than Damage-Includes t/&inch at the joint Vault repaired so Cracks in Walls of any inletloutlel that no cracks exist A Structure , Bottom, Damage to pipe or evidence of wider than t/4-inch Frame and/or Top soil particles at the joint of the Slab entering through the inletloutlel pipe. cracks. -;, Ri r~ Fencing/Shrubbery Screen/Other Landscaping Checklist FREOUENCV DRAINAGE SYSTEM DATE PROBLEM CONDITIONS TO CHECK CONDITIONS THAT SHOULD FEATURE FOR EXIST M General Missing or Any defect in the fence or Fence is mentletl or shrubs broken padsl screen that permits easy entry replacetl to Corm a solid bartier tleatl to a facility. to entry. shrubbe M,S General Erosion Erosion has resulletl in an Replace soil untler fence sc opening untler a fence that that no opening exceetls 4 allows ent b eo le or pets. inches in height. M General Unruly Shrubbery is growing out of Shrubbery is trimmed and vegetation control or is infestetl wiN weetletl to provitle appealing weetls. aesthetics. Do not use chemicals to control weetls. A Fences Damagetl Posts out of plumb more than Posts plumb to within 1-1/2 pads 6 inches. inches of plumb. A Fences Damaged Top rails bent more than 6 Top rail free of bends greater parts inches. than linch. A Fences Damagetl Any pan of fence (inGUtling Fence is aligned antl meets parts posts, top rails, and fabric) tlesign slantlartls. more than 1 toot out of design ali omen[. A Fences Damagetl Missing or loose tension wire. Tension wire in place and parts holding fabric. A Fences Damaged Missing or loose barbed wire Barbed wire in place with less parts that is sagging more than 2-1/2 Than'/.-inch sag between inches between posts. posts. A Fences Damagetl Extension arm missing, Extension arm in place with no parts broken, or bent out of shape bends larger than'/.inch. more than 1-1/2 inches. A Fences Detedora[ed Pan or pads that have rusting Structurally atlequale posts or pain( or or sraling contliticn that has parts with a uniform protective protective affectetl structural adequacy. coating. coating M Fences Openings in Openings in fabric are such No openings in fabric. fabric that an 8-inch tliameter ball could fit throw h. If you are unsure whether a problem exists, please contact a Professional Engineer. KnY (M) Monthly from November through April. (A) Once in late summer (preferable September). (S) After any major storm (use 1-inch in 24 hours as a guideline). Grounds and Landscape Checklist FREODENCY DRAINAGE SYSTEM DATE PROBLEM CONDITIONS TO CHECK CONDITIONS THAT SHOOLO FEATORE FOR EXIST M General Weetls Weetls growing in more than Weetls present in less than 5 (nonpoisonou 20 % of the lantlsmpetl area of the landscaped area. s trees antl shrubs onl M Geneal Insect hoard Any presence of poison ivy or No poisonous vegetation or other poisonous vegetation or insect pests present In insect pests. lantlsm ed area. M,5 General Trash or litter See Pontls Checklist See Ponds Checklist M,5 General Erosion of Noticeable rills are seen in Causes of erosion are Grountl landscaped areas. itlentiFletl antl steps are taken Surface to slow down/spread out the water Erotletl areas are filled, contoured, antl seedetl. A Trees antl Damage Limbs or parts of trees or Trim trees/shmbs to restore shrubs shrubs that are split or broken shape. Replace trees/shmbs which affect more than 25% of with severe tlamage. the total foliage of the Tree or shrub. M Trees and Damage Trees or shrubs that have Replant tree, inspecting for shrubs been blown tlovm or knocketl injury to stem or roots. over. Replace if severe) tlama etl. A Trees and Damage Trees or shrubs which are not Place slakes and rubber- shrubs adequately suppodetl or are mated ties around young leaning over, causing treeslshrubs for support. exposure of the roots. If you are unsure whether a problem exists, please contact a Professional Engineer. _Key_ (M) Monthly from November through April. (A) Once in late summer (preferable September). (S) After any major storm (use 1-inch in 24 hours as a guideline). Drywells, French Drains, or Downspouts Checklist INSPECTION AREA FREQUENCY LOOK FOR ACTION ~~ Downspout Annually Water overtlowing from the First clean the gutters and downspout over the ground. downspouts. If this doesn't solve the problem, a larger d ell ma be re wired. Roof Annually Moss and algae taking over the Disconnect flexible part of the shadier parts of the shingles. downspout leading to [he drywell. Remove moss. Pressure washing or use of fatty acid solutions instead of highly toxic pesticides or chlorine bleach is preferred. Install a zinc strip as a preventative. c._ r e~ RESOURCE LISTING If you suspect a problem exists, please contact your local jurisdiction at one of the numbers below and ask for Technical Assistance. Contact Numbers: City of Yelm Public Works (360) 458-8406 WSU Cooperative Extension (253) 798-7180 Developer Information: Client Name Jack Long Address The One Eleven Building City, ST Zip Auburn, WA 98002 Phone (253)846-5756 Engineer's Information' PETRA ENGINEERING 535 Dock Street -Ste. 213 Tacoma, WA 98402 (253)752-7617 LOG SHEET Use log sheets to track maintenance checks and what items, if any, are repaired or altered. The completed sheets will serve as a record of maintenance activity and will provide valuable information about how your facilities are operating. Log sheets should be kept in a dry, readily accessible place. INSPECTION DATE: PERFORMED BV: PHONE NUMBER: ADDRESS: POSITION ON HOA: CITY, ST, ZIP: _ _-_ - ~ _. i -__. __ ., 144 rtv:,= _c.'4.v' .~E 22 GLOSSARY BEST MANAGEMENT PRACTICE (BMP)_- Structures, conservation practices, or regulations that improve quality of runoff or reduce the impact of development on [he quantity of runoff. BIOFILTER (SWALE) - A wider and flatter vegetated version of a ditch over which runoff flows at uniform depth and velocity. Bioflters pertorm best when vegetation has a thick mat of roots, leaves, and stems at the soil interface (such as grass). BIOFILTRATION -The process through which pollutant concentrations in runoff are reduced by filtering runoff through vegetation. BUFFER -The zone that protects aquatic resources by providing protection of slope stability, attenuation of runoff, and reduction of landslide hazards. An integral part of a stream or wetland ecosystem, it provides shading, input of organic debris, and coarse sediments to streams. It also allows room for variation in stream or wetland boundaries, habitat for wildlife, and protection from harmful intrusion. CATCH BASIN - An inlet for stormwater set into the ground, usually rectangular and made of concrete, and capped with a grate that allows stormwater to enter. CHECK DAM -Adam (e.g., rock, earthen, log) used in channels to reduce water velocities, promote sediment deposition, and/or enhance infltration. COMPOST STORM WATER FILTER - A treatment facility that removes sediment and pollutants from stormwater by percolating water through a layer of specially prepared bigleaf maple compost. CONSTRUCTED WETLAND - A wet pond with dead storage at varied depths and planted with wetland plants to enhance its treatment capabilities. CONTROL STRUCTURE (FLOW RESTRICTOR) - A manhole and/or pipe structure with aflow-regulating or metering device such as a weir or plates with small holes known as orifces. This structure controls [he rate at which water leaves the pond. CONVEYANCE -A mechanism or device for transporting water including pipes, channels (natural and man-made), culverts, gutters, manholes, etc. CRITICAL AREA -Areas such as wetlands, streams, steep slopes, etc. as defined by ordinance or resolution by the jurisdiction. Also known as "environmentally sensitive areas" CULVERT - A conveyance device (e.g., concrete box, pipe) that conveys water from a ditch, Swale, or stream under (usually across) a roadway or embankment. DEAD STORAGE -The volume of storage in a pond below the outlet that does not drain after a storm event. This storage area provides treatment of [he stormwater by allowing sediments to settle out. DETENTION FACILITY -A facility (e.g., pond, vault, pipe) in which surface and storm water is temporarily stored. DETENTION POND - A detention facility in the form of an open pond. DIS_P_ERSION TRENCH - An open-top trench filed with riprap or gravel [hat takes the discharge from a pond, spreads it out, and spills (bubbles) the flow out along its entire length. Dispersion trenches are used to simulate "sheet flow" of stormwater from an area, and are often used to protect sensitive adjacent areas, such as wetlands. DRAINAGE SYSTEM -The combination of Best Management Practices (BMPs), conveyances, treatment, retention, detention, and ouffall features or structures on a project. DROP STRUCTURE - A structure for dropping water to a lower elevation antl/or dissipating energy. A drop may be vertical or inclined. ~:_~~~ ne. u.c' DRY PONE] - A detention facility that drains completely after a storm. This type of pond has a pipe outlet at the bottom. EASEMENT -Aright afforded a person to make limited use of another's real property. Typical easements are for pipes or access to ponds, and may be 15 to 20 feet wide. EMERGENCY OVERFLOW OR SPILLWAY - An area on the top edge of the pond that is slightly lower in elevation than areas around it. This area is normally lined with riprap. The emergency overflow is used only if the primary and secondary outlets of the pond fail, in the event of extreme storms, or if the infiltration capability of the pond becomes significantly diminished. If the emergency overtlow ever comes into play, it may indicate the pond needs to be upgraded. ENERGY DISSIPATER - A rock pad at an outlet designed to slow the velocity, spread out the water leaving the pipe or channel, and reduce the potential for erosion. FREEBOARD -The vertical distance between the design high water mark and the elevation of the top of the pond. Most ponds have one to two feet of freeboard to prevent them from overflowing. INFILTRATION -The soaking of water through the soil surface into the ground (percolation). (Many ponds are designed to fully infiltrate stormwater, and thus do not have a regularly used discharge pipe.) INFILTRATION FACILITY (or STRUCTURE) - A facility (pond or trench) that retains and percolates stormwater into [he ground, having no discharge (to any surface water) under normal operating conditions. JUNCTION -Point where two or more drainage pipes or channels converge (e.g., a manhole). JURISDICTION -Olympia, Lacey, Tumwater, or Thurston County (as applicable). LINED POND or CONVEYANCE - A facility, the bottom and sides of which have been made impervious (using, for example, a plastic liner or clay/silt soil layer) to the transmission of liquids. LIVE STORAGE -The volume of storage in a pond above the outlet that drains after a storm event. This storage area provides flood control and habitat protection for nearby streams. MANHOLE -A larger version of a catch basin, often round, with a solid lid. Manholes allow access to underground stormwater pipes for maintenance. NATURAL CHANNEL -Stream, creek, river, lake, wetland, estuary, gully, Swale, ravine, or any open conduit where water will concentrate and flow intermittently or continuously. OIL-WATER SEPARATOR - A structure or device used to remove oil and greasy solids from water. They operate by using gravity separation of liquids that have different densities. Many catch basins have a downturned elbow that provides some ail-water separation. OUTFACE -The point where water flows from aman-made conduit, channel, or drain into a water body or other natural drainage feature. RETENTION FACILITY - An inf Itration facility. RETENTION POND - A retention facility that is an open pond. REVETMENTS -Materials such as rock or keystones used to sustain an embankment, such as in a retaining wall. RIP RAP -Broken rock, cobbles, or boulders placed on earth surfaces, such as on top of a berm for the emergency overflow, along steep slopes, or at the outlet of a pipe, for protection against the action of water. Also used for entrances to construction sites. RUNOFF-stormwater. SAND FILTER -A treatment facility that removes sediment and pollutants from stormwater by percolating water through a layer of sand. STORMWATER -That portion of precipitation that falls on property and that does not naturally percolate into the ground or evaporate, but flows via overland flow, channels or pipes into a def ned surface water channel, or a constructed infllration facility. Stormwater includes washdown water and other wastewater that enters the drainage system. SWALE - A shallow drainage conveyance with relatively gentle side slopes, generally with flow depths less than one foot. This term is used interchangeably with "BIOFILTER". TRASH RACK or BAR SCREEN - A device (usually a screen or bars) that fits over a pipe opening to prevent large debris such as rocks or branches from entering and partially blocking the pipe. WET POND - A stormwater treatment pond designed with a dead storage area to maintain a continuous or seasonal static water level below the pond outlet elevation.