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Storm Maint Plan 001SAMANTHA RIDGE Operation & Maintenance Plan Prepared for: Jack Long The One Eleven Building Auburn, WA 98002 (253) 846-5756 November 30, 2007 Prepared by: Pete Swan 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 (11.30.07).doc E~' Err~rrr~~zzm~~, t ~~~ _ r b95000H 87flEET•aUfiE213 TTACOMA I'WAI 964021 PHONE (259(]52-]61] I EA%(253)]81-0592 i NNJN(.PETRAENG.NET TABLE OF CONTENTS I. STORMWATER FACILITY MAINTENANCE GUIDE 3 INTRODUCTION 3 What is Stormwater Runoff? 3 What is a Storm Drainage System and haw does it work? 3 What does Stormwater Runoff have fo do with Water Quality 3 Your Stormwater Facility 3 Who is Responsible for Maintaining Stormwater Facilities 3 How to Use the Stormwater Facility Maintenance Guide 4 Included in This Guide 4 A Regional Approach to Stormwater Management 4 YOUR STORMWATER FACILITIES 4 FACILITY KEY 4 SITE PLAN 5 QUICK LIST 0 MAINTENANCE CHECKLISTS ~ Detention Pond Checklist (1 Control Structure Checklist 11 Catch Basin Checklist 13 Vortechs Model 2000 Checklist 16 Fencing/Shrubbery Screen/Other Landscaping Checklist 17 Grounds and Landscape Checklist 18 Drywells, French Drains, and Downspout Checklist 19 MAINTENANCE COST ESTIMATE 20 RESOURCE LISTING 21 GLOSSARY 22 r ~ANTHA R 33~ '73.1' ;- I. STORMWATER FACILITY MAINTENANCE GUIDE INTRODUCTION What is Stormwater Runoff? When urban and suburban development covers the land with buildings, streets and parking lots, much of the native topsail, duff, trees, shrubs and grass are replaced by asphalt and concrete. Rainfall that would have soaked directly into the ground instead stays on the surface as stormwater runoff making its way into storm drains (including man-made pipes, ditches, or Swale networks), stormwater ponds, surface 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 fish andlor drinking water supplies. The storm drain system provides a safe method to carry stormwater to the treatment and storage area. Swales and ponds flier 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 [o 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, stormwater is recognized as a major threat to water quality. Remember to keep everything out of stormwater systems except [he 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 to provide storage for stormwater and allow for its gradual release downstream or into the ground. The private stormwater facility for this project includes a water quality LCF vault, a stormwater 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 stormwater 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. ~,,,., _.,,. 'AG[ 3 How to Use the Stormwater Facility Maintenance Guide This Maintenance Guide includes a Site Plan specifc 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 [o help you identify the more routine needs of your facility. Included in This Guide ^ Comprehensive Maintenance Checklists that provide specfiic 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 II 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 that 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. FACILITY KEY The stormwater facility in your neighborhood is comprised of the following elements: Type of Feature & Checklist Name Location on Site Plan Detention Pand ~ Control Structure 2 Catch Basins 3 Vortechs Model 200 4 Fencing/Shrubbery Screen/Other Landscaping 5 Grounds and Landscape 0 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. ~c.~ gar o° 'ice s SITE PLAN S .ti ~. tisaROGe ,..~ ace=. 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 the grate rf it is broken. O Inspect inlet and outlet pipes for blockages. Clear ail 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 them. ~ N'NF ='IDGE OSS9.J) PN6E6 MAINTENANCE CHECKLISTS The Maintenance Checklists in this packet are for your use when inspecting the stormwaler facilities on your property. This packet has been customized so that only the checklists for your facilities are included I(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 track maintenance of your storm drainage system. Although it is not intended for the maintenance survey to involve anything too difficult or strenuous, there are a few tools that will make the job easier and safer including: ^ A Flashlight ^ 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 facilities. SAFEN 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 confined spaces. NO PART OF YOUR BODY SHOULD BREAK THE PLANE OF THE OPEN HOLE. SAM'.NT;1A 31~GL udt~.0~ ~.: IS18 DGc ._~~.. N,CEIl Detention Ponds Checklist Dale Drainage Contli[ion Condition sTha[. Fre uenc V .System Problem s to Should Y Feature O'~e O+a Our p+ts Check For Fxist Any t25h antl tlebris which exceetl 5 wbic feel per 1,000 square feet (this is about equal to the amount of trash it wouM take to fill up one stantlartl size garbage can). In Trash and tlebds M,S Geneal Trash 8 Debris general, there should clearetl from site. be no visual evitlence of dumping. If less than threshold all trash and tlebris will be removed as part of next schetluletl maintenance. Any poisonous or No danger of nuisance vegetation poisonous vegetation which may constitu[ea where maintenance hazartl to personnel ar Ne public maintenance might normally be. personnel or [he (COOrtlinate vAth local A General Poisonous Vegetation public. Any evitlence weed boartl) Complete antl noxious weetls of noxious weeds as emtliwtion of noxious tlefined by State or weetls may not be local regula4ons. possible. Compliance (Apply requirements of with Stale or local atlopted IPM policies eratliwtion policies for Ne use of requiretl heNicides. _ No wntaminants or Any evidence of oil, ppllutanLS present. Contaminants and gasoline, (Coordinate M,S General Pollution contaminants orother removallcleanup with pollutants local water quaky response agency). Rodents desVOyetl Any evitlence of and tlam or berm rodent holes if facility repaired. (COOrtlinate is acting as a dam or with local health M General Rotlenl Holes bens, or any evitlence department; of water piping wortlinale with through tlam or berm Ecology Dam Safety via rotlent holes. Office if pontl exceeds 10 aae-feet. Farility is reNmed to tlesign function. Dam results in change (Coordinate trapping M General Beaver Dams or function of the of beavers antl facility. removal of dams with appropriate permitting agencies) When insects such as Insects tlestroyetl or wasps and hornets removed from site. A General Insects interfere with APPly insecticides in maintenance activities. wmpliance with atlopted IPM policies. .,. aV NTHA 21DGE Tree growth does not allow maintenance Trees do not hintler access or interteres maintenance activities. with maintenance Harvesletl trees q General Tree Growth antl activity (i.e., slope shoultl be recyGetl Hazartl Trees mowing, silt removal, iota mulch or oNer vaUOdng, or beneficial uses (e.g., equipment altlers forfrewnotl). movements . If If tlead. tliseaseq or tlying trees are itlentifietl (Use a A General ceNfied Arborist to Remove hazard Trees tlelermine healU of tree or removal requirements) Slopes shouts be Erotletl damage aver stabilizetl using 2 inches deep where appropriate erosion M Side Slopes of Pontl Erosion cause of tlamage is stillprosent or where control measure(s); there is potential for a"g" rock reinforcement. planting continued erosion. of grass, compaction. If erosion is occurdng on Any erosion observed on a compacted berms a licensed M.S Side Slopes of Pontl compacted bens civil engineer shoultl be embankment consultetl to resolve source of erasion. Accumulated sediment That exceetls l0% Setlimenl Geanetl out (typically 6'to 12")of to designed Pontl the designetl pond shape and depth: M Storage Area Sediment tlepth unless pond reseetled if otherwise specified or necessary tc control affects inletting or erosion. outleWng contlibon of the hdGli . Liner is visible antl has Liner repairetl or M Storage Area Liner (If Applicable) more than three l/4- replaced. Liner is Polly inch holes in it. _ wveretl. _ Any part of berm which has se¢letl 4 inches lower than the design elevation. If settlement is apparent, measure berm to determine amount of settlement. Setlling Dike is built back to A Pond Benns (Dikes) Settlements can be an indication of the design elevation. more severe problems with the bens or outlet woBS. A licensed Gvil engineer should be consulted to tletennine the source of the settlement. Discernable water flow Through pond berm. Ongoing erosion vnth potentlal for erosion to continue. Piping eliminated. q Pontl Berms (Dikes) Piping (Recommend a Erosion potential Goetechnical engineer resolved. be called in to inspeG and evaluate rgndilion antl recommentl repair of contliticn. „ ~ AP»~ .3.1 w- :GE 10 Trees shoultl be removed. if root system is small (base Tree growth on less than4inches)the emergency spillways root system may be creates blockage lek in place. Otherxise A Emergenq Werflow/ Tree Growth roblems and ma p y the roots shoultl be S illwa p y cause failure oRhe removed and the berm berm due to restoretl. Alicensetl uncontrolled civil engineer should overto in GF g' be mnsultetl for proper bennlspillway restoration. Only one layer of rock exists above native soil in area five sguare feel or larger, or any Rocks antl patl tlepth A Emergency Overtlowl Emergency Overflowl exposure of native soil are restored to tlesign Spillway Spillway at the top of outflow slantlartls. path of spillway. (Rip- ap on inside slopes need 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). it.,...., t:e= . Control Structure/Flow Restrictor Checklist Date _. Dreina a Contlrtion Cs Thatn Freguenc System Problem sto Shoultl y Feature Ore OtA 0.,8 ': ~y9 Chock For Exist Material exceeds Control structure Trash and Debris 25% of sump depth orifice is not M General (Includes Sediment) or 1 foot below blocked. All trash orifice plate. and debris romovetl. SWCture is not Sfructure securely A General Structural Damage securely attached to attached to wall and manhole wall. outet pipe. Stmc[ure is not in upright position Structure in coned A Geneml Slmctu2l Dama a g (allow up to 10 % position. from lumb . Connections to Connections to outlet pipe are water outlet pipe are not tight; stmcturo A General Structural Damage watertight and show repaired or replaced signs of rust. and works as desi ned. Any holes-other Stmcture has no A Geneml Structural Dama a g than designed holes other than holes-in the designed holes. structure. Cleanoul gale is not Gale is watertight A Cleanout Gale Damaged or watertight or is and works as Missing missin desi ned. Gate cannot be Gate moves up and A Cleanoul Gale Damaged or moved up and tlown tlown easily and is Missing by one maintenance watertight. erson. Chain/rod leading to Chain is in place A Cleanout Gate Damaged or gate is missing or and works as Missing dama ed. desi ned. Gate is rusted over Gale is repaired or A Cleanout Gate Damaged or 50% of its surface replaced to meet Missing area. design stantlards. Control device is Damaged or not working properly plate is in place and A Orifice Plate Missing due to missing, out works as designed. of place, or bent onfce late. Any Uash, debris, plate is free of all M,5 Odfce Plate Obstructions sediment, or vegetation blocking obstructions and works as designed. the late. Any trash or debris blocking (or having Pipe is free of all Overfiow Pipe Obstructions the potential of obstructions and hlocking) the works as designed. averfiow ipe. Cover is missing or only partially in A Manhole Cover Not in Place place. Any open Manhole is closed. manhole requires maintenance. Mechanism cannot be opened 6y one maintenance person with proper Locking Mechanism fools. Bolts into Mechanism opens A Manhole Nat Working frame have less with proper tools. than i/2 inch of thread (may not apply to self-locking lids . One maintenance person cannot remove lid after Cover can be applying normal removed and q Manhole Cover Difficult to lifting pressure. reinstalled by one Remove Intent is to keep maintenance coverfrom sealing person. off access to maintenance. Ladtler is unsafe due to missing Ladder meets Ladder Rungs mngs, design standards. A Manhole Unsafe misalignment, not gpows maintenance securely attached to person safe access. structure wall, rust, or cracks. (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). ..n.°."P.NTHFl RIDGE Catch Basins Checklist DRAINAGE CONDITIONS TO CHECK CONDITIONS THAT SHOULD FREQUENCY SYSTEM DATE PROBLEM FOR EXIST FEATURE A Geneml "Dump no Stencil or stamp should be blaming signs (e.g.,'DUmp No pollutants" visible and easily reatl. Waste-Drains to Stream") shall Stencil or be paintetl or embossed on or stamp not atljacent to all stone drain visible inlets. M S Geneal Trash & Trash or tlebris which is No trash or debris located , Debris Iccatetl immetlia[ely in front of immetliately in front of catch [he catch basin opening or is basin or on grate opening. blocking inlelting capacity of the basin b more than 10%. M General Trash & Trash or debris (in the basin) No trash or tlebris in the catch Debris that exceeds 60 percent of the basin. sump tlepth as measuretl from the bottom of basin to invert of [he lowest pipe into or out of Ne basin, but in no case less than a minimum of six inches clearance from the tlebris sudace to the invert of Ne lowest i e. M General Trash 8 Tmsh or debris in any inlet or Inlet and outlet pipes hee of Debris outlet pipe blocking more than trash or debris. 1l3 of its height. M General Trash 8 Dead animals or vegetaton No tleatl animals or vegetation Debris that multl generate odors [hat present within the catch basin. mind rouse complaints or tlangerous gases (e.g., methane). M General Setliment Sediment (in the basin) that No Setliment in the catch exceeds 60 percent of the basin. sump tlepth as measuretl from the bottom of basin tc invert of the lowest pipe inW or cut of the basin, but in no rose less than a minimum of 6 inches cleaance from the Setliment sudace to the invert of the lowest e. A General SWCture Top slab has holes larger than Top slab is free of holes and Damage l0 2 square inches or cracks cracks. frame andlor witler than'/. inch (Intent is to Top Slab make sure no material is running into basin) A General Structure Frame not sitting flush on tap Fame is sitting flush on the Damage to slab, i.e-, sepaation of more riser rings or top slab antl Frame antllor than 6inch of the frame hom fnnly attached. Top Slab the top slab. Frame not securely attached. .~1-IA FiDGc -u-~ -- ."- .' Catch Basins Checklist (Continued) A Geneml Ractures or Maintenance person lutlges Basin replaced or repaired to Cracks in that stmcture is unsountl. tlesign sandards. Basin Walls! Bottom A General Factures or Grout fillet has sepaatetl or Pipe is regrouletl and severe Cracks in aaWetl wider than % inch and at basin wall. Basin Wallsl longer than 1 foot at the Joint of Bottom any inleVoutlet pipe or any evidence of soil particles entering catch basin through cracks. A General Settlement/ If failure of basin has created a Basin replacetl or repairetl to Misalignment safely, (unction, or tlesign tlesign standards. roblem. M General Vegetation Vegetation growing across and No vegetaton blocking blocking more than 10 0 of the opening ro basin. basin o enin . M General Vegetatlon Vegetatlon growing in No vegetatlon or root growth inleVoutlet pipe joints that is present. more than six inches tall and less than six inches apart. M General COnlaminatlo Any evidence of oil, gasoline. Nc wnlaminanLS or pollutants n antl mntaminanls or other present. Pollution pollutants (COOrtlinale removal/Geanup with local water quality response a enc . A Catch Basin Cover not in Cover is missing or only Any open vetch basin requires Cover place partially in place maintenance. Catch basin cover is dosed. A Catch Basin Locking Mechanism cannot be openetl Mechanism opens with proper Cover Mechanism by one maintenance person tools. Nol Working with proper tools. Bolts into frame have lessthan'/: inch of thread. A Catch Basin Cover One maintenance person Cover ran be removetl by one Cover Difficult to cannot remove lid after maintenance person. Remove applying normal lifting pressure. (Intent is keep cover from sealing oB access fo maintenance.) A Latltler Ladder Ladtler is unsafe due to Ladder meets tlesign Rungs missing mngs, not securely standaMS and allows Unsafe adachetl to basin wall, aintenance person safe misalignment, rust, tracks, or access. shar ed es. A Grates Grate Gate with opening wider than Grate opening meets design Opening ]/8 inch. standards. Unsafe M.S Gates Trash 8 Trash antl tlebris that is Grate bee of trash antl debris. Debris blocking more than 20%of grate surface inletting rapacity. `-A ftF GE 08. ri.OZ _.:GE 15 Catch Basins Checklist (Continued) A Grates Damagetl or Grote missing or broken Grate is in place antl meets Missing member(s)of the grate. design standaMS. 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) Afler any major storm (use i-inch in 24 hours as a guideline). RIDGE Vnrterhs Stormwater Treatment Svstem Checklist _______-_ - Date ~reinage Condition Condition sThaF Fre uenc 4 System_ Problem sto Shoultl y Feature Otq O'ie O'~e O'~a. Check FOr ' Exist Sediment depth is accumulated S M General Sediment within 6' of dry sediment should be , accumulation weather water removed. surface elevation. Trash and debris accumulated in Trash and debris Tash and Debris vault, or pipe removed from vault, M,S General Accumulation inleUoutlet, and inleUoutlet Floatables and non- piping. Floatables. Oil is extracted from vault using vactodng methods. Oil accumulation Coalescing plates M S General Oil Accumulation that exceeds i-inch are cleaned by , at the water thoroughly rinsing surface. and flushing. Should be no visible oil de [h on water. Inlet or outlet piping damaged or broken Pipe repaired and or A Structure Damaged Pipes and in need of replaced. re air. Baffles corroding, cracking, warping and/or showing Baffles repaired or A Structure Baffles signs of failure as replaced to determined by specifcations. maintenance/inspec tion erson. Cracks wider than 1 /2-inch or evidence Vault Structure of sail particles Vault replaced or Damage - Includes entering the repairs made so Cracks in Walls structure through that vault meets A Structure , Damage to Bottom the crocks, or design , Frame and/or Top maintenance/inspec specifrations and is Slab tion personnel s[mcturally sound. determine that the vault is not slmcturall sound. Cracks wider than Vault Stmcture t/2-inch al the joint Vault repaired so Damage-Includes of any inleUoutlet that no cracks exist A Structure Cracks in Walls, Pipe or evidence of wider than 1/4-inch Bottom, Damage to soil particles al the joint of the Frame and/or Top entering through the inlet/outlet pipe. Slab cracks. ,.1~~r. RI~G~ ,.i '~ Fencing/Shrubbery Screen/Other Landscaping Checklist DRAINAGE CONDITIONS TO CHECK CONDITIONB THAT SHOULD FREpUENCY SYSTEM DATE PROBLEM FOR EXIST FEATURE M General Missing or Any tlefed in Ne fence or Fence is mended or shrubs broken parts/ srseen that permits easy enUy replacetl to form a solid barrier tleatl to a fa0lity. to entry. shmbbe M S Gene21 Emsion Erosion has resulted in an Replace soil untler fence sc , opening under a feme that Nat no opening exceeds 4 allows ent b eo le or ers, inches in hei hl. M General Unruly Shrubbery is growing out of Shrubbery is trimmed and vegetation control or is infesletl with weedetl to provitle appealing weeds. aesthetics. Do not use chemicals to control weetls. A Fences Damagetl Posts out of plumb more than Posts plumbto within Ll/2 parts 6inches. inches of plumb. A Fences Damaged Top rails bent more than 6 Top rail free of bentls greater parts inches. Uan 1 inch. q Fences Damaged Any part of fence (including Fence is aligned antl meets parts posts, top 2ils, antl fabric) design stantlartls. more than 1 foot out of tlesign ali omen(. A Fences Damaged Missing or loose tension wire. Tension wire in place and parLS hcltling fabric. A Fences Damaged Missing or loose baNetl wire Barbed wire in place with less parts that is sagging more than 2112 than'/.-inch sag between inches between posts. posts. A Fences Damaged Extension arm missing, Extension arm in place with no pans broken, or bent out of shape bends larger than '/.inch. more than 1-1/2 inches. A Fences Deteriorated Part or pads that have rusting Structurally adequate posts or paint or or styling condition that has parts with a uniform protective protective affected structural adequacy. coating. mating M Fences Openings in Openings in fabric are such No openings in fabric. fabric Nal an 6-inch diameter ball multl fl throw h. If you are unsure whether a problem exists, please contact a 4'rofesslonal tnglneer. Kev: (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). os.'~,=. ~ =tc,=_ is Grounds and Landscape Checklist DRAINAGE CONDITIONS TO CHECK CONDITIONS THAT SHOULD FREpUENCV SYSTEM GATE PROBLEM FOR EXIST FEATURE M General Weeds Wesds growing in more than Weetls present in less than 5% (nonpoisonou 20%of the lantlscapetl area of Nelantlscapetl area. s trees and shrubs onl M General Insect hazaM Any presence of poison ivy or Na poisonous vegetation or other poisonous vegetation or insect pests present in Insect ests. IaiWSCa etl area. M,S Geneal Trash or litter See Pontls Checklist See Ponds Checklist M G General Erosion of Noticeable rills are seen in Causes o(erosion are , Grountl landscaped areas. itlentifietl antl steps are taken Surface to slow downlspreatl out the water. Erotled areas are filled cenmured, and seetletl. A Trees and Damage Limbs or parts of trees or Trim bees/shmbs to restore shrubs shrubs that are split or broken shape. Replace trees/shrubs whiGr affect more than 25% of with severe damage. the total foliage of the tree or shmb. M Trees antl Damage Trees or shrubs That have Replant tree, inspecting for shmbs been blovm tlown or knocked injury b stem or roots. over. Re lace if severe) tlama etl. A Trees and Damage Trees or shmbs which are not Place stakes antl rubber- shmbs adequately supported or are ceatetl ties around young leaning over, causing bees/shmbs for support. exposure of the mots. If you are unsure whether a problem exists, please contact a Processional tnglneer. Kev: (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). 5 ...THF. RI ~~ ?",.i _, Drywalls, French Drains, or Downspouts Checklist INSPECTION AREA FREOUENCy LOOK FOR ACTION Downspout Annually Water overFlOwing from the First clean the gutters and ' downspout over the ground. t downspouts. If this doesn 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 the drywall. 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 reventative. Maintenance Cost Estimate The estimated cost for the annual maintenance of the facilities, including removal of debris, cleaning out piping, catch basins, vortechs, pond, etc. is as follows: Clean out piping, catch basins, and vortechs - Personnel @ $25/hr for 4 hrs = $ 100 10 hours per year = $ 1,000 Detention Pond Maintenance $1,000 per year = $ 1,000 Total Estimated Annual Cost = $ 2,000 RESOURCE LISTING If you suspect a problem ezis[s, 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 Address City, ST Zip Phone Engineer's Information: Jack Long The One Eleven Building Auburn, WA 98002 (253)846-5750 PETRA ENGINEERING 535 Dock Street -Ste. 213 Tacoma, WA 98402 (253)752-7617 ,,, -,. ~iA aocc __ ~..~, : q.,~rz 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: ~ ~ •r _. _.- _. - _ - i __ _ - . _._ ~ ___ __ _. _ __. _.I. __._ '. ___ _ _. l4', hA R ~3- 2.r' 0' .{ p} GLOSSARY BEST MANAGEMENT PRACTICE (BMP1-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 perform 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 [o reduce water velocities, promote sediment deposition, andlor enhance infll[ration. 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 andlor pipe structure with aflow-regulating or metering device such as a weir or plates with small holes known as orifices. This structure controls the 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 defned 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 the stormwater by allowing sediments to settle out. DETENTION FACILITY-Afacility (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. DISPERSION TRENCH - An open-top trench filed with riprap or gravel that 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 flovJ 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 andlor dissipating energy. A drop may be vertical or inclined. na.~ne; ?nc= ax DRY POND - 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 lop edge of [he 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 infltration capability o(the pond becomes signifcantly diminished. If the emergency overflow 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 tap 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 infltrate 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 the 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 even[. 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 oil-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 overfow, 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. _. ,,,.iJvi I-~.4 NI9GE 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 defined surtace water channel, or a constructed infltration facility. Sformwater 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.