Loading...
Drainage and Erosion Control Report 012308 001DEL'S FARM SUPPLY Drainage and Erosion Control Report Prepared for: Linda Michaelis DFS Properties, LLC 'ION Fairway Drive East Hoodspart,lNA 98548 [253) 3'12-4467 Revised January 23, 2007 Prepared by: David W. 5piller, PE Reviewed by: Steven ^. Hatton, PE HATTDN G~DAT PANTIER 1840 Barnes Blvd SW Tumwater, WA 9851 ~ X350} 943-1599 Project Nv: 85-055 Project Name: ^EL'S FARM SUPPLY E:lvtfcel.tdBSl2Q05105-055-De1's Farm Supply - YeIm1RP'T- Dra i Wage-07.23.08.dvc RECEIVE^ SAN ~ 4 2088 TABLE OF CONTENTS I. YELM REGION FACILITY SUMMARY FORM .......................................................................3 II. ©RAINAGE REPORT ...............................................................................................................T Section 1 -Project gescription ........... . ........................ ............ ........... .. ................7 Sec#ion 3 -Soils Report ...... ................... .................................... ................................8 Section 4 - We11s and Septic 5ystems ...................................._...... ........................---.-...8 Section 5 -- Fuel Tanks ...................................................... . ....... ...................~~- ~~-~-~--8 Section fi -Analysis of 100-Year Flood ......................................... ................................8 Section 7 -Aesthetic Consideratians ............................................ ..•----....................---..8 Section 8 -Facility Sizing and ^ownstream Analysis ................... ................................8 Section 9 -Covenants, Dedications, and Easements ................... ..............................12 Section 10 - Articles of Incorporation ............................................ ..............................12 111. EROSION CONTROL PLAN .............•----....................._..-•---.................. ......--------..................13 Section 1 -Construction Sequence ...... .. ..................... . .......... ...................~ -- ......13 Section ~ -Trapping Sediment .............................................. . ~--. ......................---~ --13 Section 3 -site Restoration .......................... . ....................~~- ~-- ~~---.........................14 Section 4 - Geotechnical Analysis ................... ~ ----.....................-- ~ ---.........................14 Section 5 -Inspection Sequence ...... ....................... . ................ ......~~--~ - ~--~--.........14 Section fi -Control of Pollutants other than Sediments ................ ..............................14 N. STDRMWATER MAINTENANCE PLAN .....................•--•--................... .....-----._....................15 Appendix A -Site Plan Appendix 13 -Calculations I. YELM REGIGN FACILITY SUMAAARY F~RIVI Complete ^ne far each facility {detentionlretention, caafescing plate filter, etc.} on the project site. Attach 8 %" by 11" sketch showing location of facility. Proponent's facility name or identifier {e-g., Pond Ay: Name of road or street to access facility: Hearings Examiner case number: Development Review Project NoJBldg- Permit NQ_: Parcel Number{s}: Storm Pond Bald Hills Road fi43O32OO7QO,fi43O3200704 To Be Completed By Utility Staff: Utility facility number :........................................ ~ -~----~~--~~- Parcel number status, {num, 1ch} ..................................... ~-Known; 1-Public; 2-Unknown; 3-Unassigned Basin and sub-basin, {num, fish} ....................................... {2ch-Basin; 2ch-Sub-basin; 2ch-Future Responsible jurisdiction, [alpha, 1ch} ................................ D-Dlympia; C-County; T-Tumwater; L-Lacey Part 1 - Project Name and Proponent Project name: Del's Farm Supply Project owner: ^FS Properties, LLC _~ Project contact: Linda Michealis Address: 'ION Fairway Drive East, Haadsport, WA 98548 __ Phone: {36O} 8TT- 5420 ,. . Project proponent (if different}: pFS Properties, LLC Address: 1ON Fairway Drive East, Hoadsport, WA 98548 Phone: Project engineer. Steven ^. Hatton, PE Firm: HATTQN GGDAT PANTIER Phone number. {36Oj 943-'[599 ^EL'S FRRM SUPPLY a1-23.2068 PRGE 3 Part 2 -Pro ect Location 5ection.......-._-- Township ........ ........... 24 ---~ - ~- 1TN Range .................... ........ 1E Names and addresses of adjacent property owners: Part 3 -Type of Permit ApRiication Type of permit [e-g_, commercial fJUilding}: Dther permits [®}: ^ ^DF IUV HPA ^ CDE Wetlands ^ FEMA ^ Shoreline Management ^ Encroachment ® Other Building Site Plan ^ CDE A04 ^ DDE Dam Safety ^ Floodplain ^ RockerylRetaining Wall ® Grading Dther agencies (Federal, State, Local, etc.} that have ar will review this Drainage and Erasion Cantroi Plan: NINE ^EL'S FAR]VI 5Uf'PLY 01.23.24fl8 PAGE 4 Part 4 - Proposed Protect ^es~ription What stream basin is the projec# in [e.g., Percival, Woodland, etc.]? Zoning :......................... Commercial C-'I ~nsite: Residential Subdivision: Number of lots ............................~- -......................... Lot size [average, ages} .......................................... Building PermitlCammercial Plat: Buildings} [footprint, acres} ..................................... Concrete paving [acres] ........................................... Gravel surface [acres} .............................................. Lattice 61ock paving (acres} .............. .... . ................... Public roads-including gravel shoulder {acres ........ Private roads-including gravel shoulder [acres]....... Onsite imper~ivus surface fatal [acres ..................... Part 5 -Pre-de~ela ed Pro-ect Site Characteristics: Stream through site [yln} ......................................NO Name ......... ............................... NIA ^NR Type ................. . ~- ~--.......... NIA Yelm 0.29 Type of feature this facility discharges to [i.e., lake, stream, intermittent stream, pothole, roadside ditch, sheetflow to adjacent property, etc_}: TYPE OF GiSCHARGE _ lnfiltration Swales [y!n}.....- • . ................................ . ........ N Steep slopes-steeper than t0°I° {y!n} ---------------------- N Erosion hazard [Y~n} • ........................... . -- N SDfl-year flaodplain [Y~n)-~ ••- . ...................... Y Wetlands [y!n} ...... . .............................. • - ....... N 5eepslsprings [yln} • ~ . ........................ - ~- ~- N High groundwatertatale [yln} ................................... Y Other ...................................................................... N ^EL'S FARltiel 5i1PPLY 01.23.2fl08 _. _....._. PAGE 5 Part 6 -Facility description Total area tributary to facility including offsite [acres] ................. Total onsite area Tributary to facility [acres} ................................. Design imper-rious area tributary to facility [acres}---------------------- Design landscaped area tributary to facility {acres} ..................... Design total tributary area to facility [acres} ................................ Enter "1" for type of facility: Wet pond detention.-- ---- ~-~~- ~-- ~-~ -......--~ ............... 1 Wet pond water surFace area {acres} ..................... Dry pond detention ................................................. - tJndergraund deten#ion ........................................... - Infiltration pond ....................................................... ____ Drywekl infiltratian........---~~--~ .................................... -_ Coalescing plate separator ..................................... Centrifuge separator ............................................... -_ Other .........................................•--•-----------•------•-•---- cutlet type {enter "1" far each type present}: Filter ........................................................................ Cillwater separator ................................................. _._.._... Single arifice....._.-... ~-- .._..-... -~ - ~- ~- - ~- ~- - Multiple ^rit"ECes - ~ -- - ~ - - - ~ ~ ~ ~ --~~-- - 1 Weir ........................ ~ -- ~ -... ~ ~ - ~-~ - ~- ~ - -- --~ 5pillway ................................................................... ~_ Pump{s} .................................................................. Dther ...................................................................... ~"__._-~ Part T - Release to Groundwater 2.59 2.18 1.97 8.513 2.59 Design percokation rate to groundwater {if applicable} -------------------------NSA Part 8 -Release to Surface Water fif applicable] Thurston County MSL. Percent ^esign discharge Tv Surface Efe--ation Ift.] Fall Volurne fcu. ft.l Water fcfsl 34fi.00 _._...__. __ __ _0 _. ._._ .~ 0.00 0.00 347.00 .- _ _ _ 25 12,110 ~-027' 348.00 50 25,003 0.04fi 350.1]0 100 55,670 34.79 01-23-2fl08 PAGEfi DEL'S FARM Sl1PPLY II. DRAINAGE REPORT Seetian 1 -Project Description This project proposal seeks approva! to improve the existing Del's Farm site. The projec# will consist of frontage improvements along Bald Nills Road including replacement of fencing, adding new pavement, and increasing the number or parking spaces. The site currently has two buildings consisting of an 8,205 sf retail lauilding and a 4,320 sf storage barn on 7.47 acres. The site is located east of the intersection of Yelm Avenue {SR 507} and Bald Hills Road. The Tax f arcel Numbers for this project are 643032U0700 and fi430320fl704. The site is zoned Commercial (G-1}, which allows the use. Stormwater improvements will be provided onsite far the project. City water and sewer service is available at the site and is proposed to service the site. This project will require site plan approval, grading and right-of--way permits_ Stormwater Best Management Practices will be provided for the project including water quality treatment. Treatmen# will consist of a wet pond for Bald Hills Road improvements and far the onsite impervious areas. The wef pond is designed to treat the 8-month event_ Stormwater quantity runoff impacts are mitigated lay an onsite pond. Appendix A contains a reduced copy of the site plan. Approximately 4.9 acres of the site will remain in an undeveloped condition. In addition, portions of the undeveloped area are being dedicated to the City for Yelm Avenue and Bald Hills Road. .. ' , :::.:';° :. laeseriptian ~... . lmperviaus Area [ac}' `:- `:..:Total Area ~acj: Area draining to pond Bald Hills Road [offsite} 0.32 0.41 Parking lot and roof area 1.fi5 2.Ofi Pond area 0.12 0.12 Sub Total 2.179 2.59 Area draining to existing dry well 0.50 0.5Q Area draining to landscaping 0.11 0.11 Area to remain in natural condition not drainin to and 3.55 Total 2.70 fi.75 Section 2 -Existing Conditions There is no significant offsite drainage tributary to the storm facilities. The Yelm Avenue right-of--way is located north of the site, and is lower than both the site and the parcel. The crown of bald Hills Road prevents water from entering the drainage system from the southwest. The site generally drains to the eas#, at a maximum grade of 3°I°. The site is located within an aquifer recharge area. A small stream is located near the easf property Line. There are n^ other known wetlands, gullies, steep slopes, springs, or other environmentally sensitive areas on site ^r immediately down grade of the property. _...._..__. _T T__......... ...................... ~.................... EEL'S FARM SUPPLY 61.3.?.~08 PAGE 7 Section 3 -Sails Depart The Thurston County Soils map list the soils an the site as Spanaway gravelly sandy loam. Infiltration rates far Spanaway soils are generally considered rapid. However insufficient separation between ground water and finished grades prevents the use of infiltration on #his site. Section 4 -Wells and Septic Systems Records at Thurston County and the Department of Ecology were searched in order to locate wells and septic systems that may be located within the setback distances from the stormwater pond or ponds. In addition, the Project Engineer, or someone under his direct supervision, has visited the site to verify the presence or absence of wells and septic systems as best can be done visually without trespassing onto other properties. All wefts and septic systems found to be located within the setback dis#ances from the stormwater pond, or ponds, have been shown an the plans. Section 5 -Fuel Tanks Records at Thurston County and the ^epartment of Ecology were searched in order to locate the presence of above and below ground fuel storage tanks thaf may be located within the setback distances from the s#ormwater pond or ponds. In addition, the Project Engineer, ^r someone under his direct supervision, has visited the site #o verify the presence or absence of fuel tanks as best can be done visually wi#hout trespassing onto other properties. All fuel tanks found to be located within the setback distances from the starmwater pond or ponds have been shown on the plans. Section fi -Analysis of 1~a-Year Flood The Federal Emergency Management Agency prepares maps far all areas within Thurston County, including the incorporated cities therein. Panel #530188 0355 ^ depicts the areas, if any, subjected to flooding in the vicinity of this proposal. By inspection of this map, this development area of this proposal appears to be located in Zone X, an area determined to 6e outside the 100-year flood plain. The east portion of the site is located in a Zone A7 with elevations between 344 and 345. Section 7 -Aesthetic Considerations All stormwafer facilities will be hydroseeded upon completion. Additional landscaping shall also be provided throughout the project in conformance with the approved landscaping and tree restoration plan, as applicable, and as otherwise required by the approving authority. Section 8 -Facility Sizing and Downstream Analysts This project has been designed per the requirements of the Stormwater Management Manual for the Puget Sound Sasin published in 2x03 which was developed by the Washington State Department of Ecology. The stormwater conveyance system and drainage control features have been analyzed using the WWHM computer modeling software. A copy of the WWHM model is located in Appendix C. DEL'S FARM SUPPLY 6~.23.2a68 PAGE S Pond 5izin Pre~ieveloped Site Hydrology: The pre-developed conditions for starmwater modeling purposes way set to forested conditions per the requirements of the ^rainage Manual. The sails are tills. The site was divided into two basins, Basin 1 is the parking lot and pole barn, Basin 2 consists of the frontage improvements. Basin 1: Basin 2: Acreage: 2.18 ac Soil Group: Tili Modeled as: Forested Acreage: 0.41 ac Soil Group: Till Modeled as: Forested Pre-Developed Condition Event output: WWHM version 2.D Return Period Total Flow Rate [cfs} 2-Year D.D7 5-Year fl.11 10-Year D.14 25-Year D.18 50-Year 0.18 100-Year D.21 Developed Site Hydrology: The parking lot consists of landscaping, roof area, and paved parking areas. The soils are tills. Basin 1: Land use and Cover Condition: Parking Lat Paved and Building Modeled as: StreetslsidewalksJparking Acreage: 1.85 ac Modeled as: Pasture Acreage: 0.41 ac Modeled as: Pond Acreage: 0.12 ac Soi! Group: ^utwash Basin 2: Land use and Cover Condition: Street Improvements Modeled as: 5treetsJsidewalkslparking Acreage: D.32 ac Modeled as: Landscaping Acreage: D.D9 ac Sail Group: Gutwash ^EL'S FARA+I SUPPLY 01.232~p8 PAGE 9 ~e--efoped Unmitigated Condition Event Dutput: INWHM version 2.fI Return Period Fl a w Rate Total ~~ ,, r { SCE 2-Year 0.52 5-Year 0.63 10-Year 0.69 25-Year 0.77 50-Year 0.83 100-Year 0.89 QEL'S FARM SUPPLY 01.23.2608 PAGE 16 Discha a Structure Riser Height Riser Diameter Qrifire 1 ^iameter Notch Type Notch Height Notch Width 3 feet 18-inch 1.OD inch Elevation D feet Rectangular 1.17 0.04 NOTE: Elevation is measured from the pond bot#om. Pond Dimensions Depth 4 feet bottom Length 105-75 feet [plans 224 feet} Bottom Width 105.75 feet (plans 5D feet] Side Slopes 3:1 Volume at Riser Head 0.909 acre-feet Developed Condition Event Output: WWHM version 2.[) Return Period Pre-Developed Developed with Developed w1 Flow Rate cfs n^ and Pond Flow Rate 2-Year 0.07 D.52 0-D54 5-Year D.11 D_63 0.D85 1 D-Year D.14 D.69 D.11 25-Year D.16 0.77 D.14 50-Year 4.18 0.83 Q.17 100-Year 0.21 D.89 0-20 Wet Pond Sizin :The wet pond was sized to meet the '#995 Washington State Department flf Ecology's standards for the Puget Sound Basin {DDE}. The pond will treat the onsite parking, frontage improvements, and roof area. The DOE standard is a pond with a permanent pool depth of 3~ feet deep, and a minimum volume equal to 6-month rainfall event. Step 1 }Calculate the volume of the fi-month event_ WWHM estimates the volume of the fi-month event to be D.11-fi5 ac*ft (5,075 cf}. Step 2} Confirm the wet pond volume is provided by the proposed pond. The plan is fora 3-foot deep we# pond with a bottom area of 15 by 65 feet_ The wet pond will be located in the bottom of the detention pond, and additional treatment will be provided by the deten#ion pond bottom. An Excel spread sheet was used #o estimate the volume of a 15 x 65 foot pond with 3 tot side slopes to be 5,348 cf [0.1228 ac""ft} at 3 feet deep- Use a 15 x 65 foot pond bottom with 3 to 1 side slopes for the wet pond. QEL'S FARM SIJPPI_Y fl1.23.2QD8 ~ ...PAGE 13 5ectivn 9 - Ca~enants, Dedications, and Easements All stormwater facilities located on private property shall be owned, operated, and maintained by the property owners, their heirs, successors, and assigns. The property owners shall enter into an agreement with the governing body, a copy of which is included in Part V of this report. The agreement requires main#enance of the stormwater facilities in accordance with the maintenance plan provided and shall grant easement for access to the governing body to inspect the stormwater facilities. The agreement also makes provisions for the governing body to make repairs, after due notice is given #o the owners, if repairs are necessary to ensure proper performance of the stonnwater system and if the owners fail to make the necessary repairs. The cost of said repairs shall t}e borne 6y the property owners, their heirs, successors, and assigns_ 5ectinn 18 -- Articles of Incorporation Not applicable. pEL'S FARNf SE]PPLY 01.23.208 PAGE 12 III. EROSION CONTROL PLAN Section 1 ~-Construction Sequence Prier to commencing any grading or filling upon the site, all erasion control measures, inckuding installation of a stabilized construction entrance, shall be installed in accordance with this plan and the details shown ^n the drawings. More specifically, the following construction sequence shall be observed: 1. Construction vn this site shall he conducted substantially in accordance with the construction sequence described on the plans and in this erosion control plan. t7eviations from this sequence shall be submitted to the project engineer and permitting jurisdiction. ~eviatians must be approved prior to any site disturbing activity not contained within these plans. 2. Far each phase of the developmen# of this site, the fallowing general sequence shall be observed: a. Install perimeter frlter fabric fence as shown. b. Install inlet protection for existing inlets in the vicinity of areas to be disturbed. c. Call for inspection by the project engineer. d. Construct temporary sedimentation traps] and outle#[sy. e. Perform grading directing site runofF towards the sediment trap prior to discharge from the site. f. Instal! temporary piping, as required, to direct runoff towards the sediment trap. 3. Once the site is disturbed, continue operations diligently toward completion. 4. Monitor alk erosion control facilities, and repair, modify, or enhance as directed or as required. Section 2 -Trapping Sediment Protection of offsite properties against sedimentation is an absolute necessity. Additional measures may be required #a provide full protection of downstream areas. Additional measures may include, but are not limited to, use of sediment bags in existing catch basins, increased filters within sediment ponds such as hay hales, introduction of coagulants to the sediment ponds, and other such measures. Continuous monitoring of the erosion control systems, depending upon site and weather conditions, shall be ongoing throughout project development. Vehicle tracking of mud offsite shall be avoided_ Installation of a stabilized construction entrance shall be installed at the start of construction at the exit point to he used by the equipment. This en#rance is a minimum requirement and may he supplemented if tracking of mud ^n#o public rights-of-way becomes excessive. Washing down roads daily to remove excessive mud may he required. Wash water shall be directed to the temporary sediment traps installed ansite and shall not be allowed to discharge downstream without treatment. r]E[_ 5 FARM 5l1PPLY _ 01.23.~flD8 PAGE 13 Section 3 -Site Restoration ^isturtred areas on and offsite sha[I he hydroseeded or otherwise landscaped or stabilized upon project completion to provide permanen# erosion control where required. Erosion control measures shall remain in place until final site stabiliza#ion is imminent (e.g., paving scheduled with a favorable weather forecast}. Section 4 - Geotechnica! Analysis Existing slopes in the area of the stormwater ponds are at a maximum of 3°I4. The temporary sediment ponds will be excavated into the native soil. No embankment is required. Section 5 - Inspection Sequence The projec# Engineer, ar someone under his direct supervision, and the permit authority shall inspect the #emporary erasion control facilities construction entrance, sediment (raps, and erosion control barriers} prior to commencement of construction. ^uring and following construction, the Engineer shall inspect the construction of the permanent stormwater facilities and report to the permit authority his findings as to performance and operability of the completed system. Section 6 -Control of Pollutants other than Sediments A centralized equipment marshalling area and containment area is to be provided onsite for equipment maintenance and storage of any equipment service materials. An area onsite will be selected as a temporary debris and stockpile area for materials that will be removed from the site. Erosion control containment and harming of this area will be provided for pollutant can#ainment and sheeting provided for coverage or lining if applicable. gEL'S FARM SLfPPLY 01.23.2068 PRGE 14 lV. ST~RMWATER MAINTENANCE PLAN DEL'S FARM SUPPLY REVISED JANUARY 23, 2UD8 ^EL'S FARM SUPPLY a1.7.3.2D68 PAGE 15 TABLE ~F CONTENTS 11. STDRMWATER FACILITY MAINTENANCE Gl1l0E ........................................................................17 INTROf3UCTI~N ........................... ................. ............. ............. ............ ......................... ..........17 What is Stormwater Runoff? .................... ................~.............-......---... ......_..................-- -......17 What is a Storm ^rain System and how does it Wark? ........................ ....................................17 What does Stormwater Runoff have to do with Water Quality? ............ ..................................17 Your Stomjwater Facility ..................:.................................................... ....................................17 Who is Responsi171e for Maintaining 5tormwater Facilities? ................. ....................................17 How to Use the 5tormwater Facility Maintenance Guide ..................... .....................................18 included in This Guide .................................................. .. ............. .... .............. .....................18 A Regional Approach to Stormwater Management .............................. .....................................18 YOUR ST~RMWATER FACILITIES ............. ........................................ ............. ~-~---.................18 FACILITY KEY .................. ................................ .................. ............... ... .............. ......................18 SITE PLAN ........................ ................. .................................................... .....................................19 QUICK LIST .............................................. ............. ................... ............ ... .................... .........20 MAINTENANCE CHECKLISTS ............... .............................................. ........ ................~~ - ~ ....21 Ponds ............ . ................................. .................. ~~---........... -............ ..-- ---...............----~--......22 Catch basins, Manholes and Inlets .... .............. ~-- .............. --.........-- ~~---~ --......................-.....24 Conveyance Pipes, Ditches and Swales ............................................. .....................................26 Grounds and Landscaping- ~ ................. ................ ~ -.............._......... ........---._......---...........- --27 RES~URCIr LISTiNG ............... ............................................................... ........... ........................28 III. POLLUTION SOURCE CONTROL pROGRAM ................................................................................3d What Are Pollution Source Controls and Why Are They Needed? ...... .....................................3~ Materials Used and Wastes Generated ............................................... .....................................30 Required Actions ............. ............... ................. ~---.............-- ~--......... ....... ~-- -.....---.........-~- -30 ^EL'S FARfN 5L1P~LY Q1-23-2008 PACE 15 II. ST~RIIAWATER FACILITY MAINTENANCE GUIDE 1NTROOLICTION What is Stnrmwater Runoff? When urban and suburban development cavern 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 sur#ace as sformwaterrunofl making its way into storm drains (including man-made pipes, ditches, or swale networks}, starmwater ponds, surface and groundwa#er, and eventually to Puget Sound. What is a Storm Orain System and how does it Wark? The storm drain system for mos# developments includes measures to carry, stare, cleanse, and release the starmwater. 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 pallutior~ which harms fish andlar drinking water supplies. The storm drain system provides a safe method to carry starmwater to the treatment and storage area. Swales and ponds filter pollutants from the starmwater by physically settling out particles, chemically binding pollutants to pond sediments, and biologically converting pollutants to less harmful compounds. Ponds also stare treated water, releasing it gradually to a nearby stream or to groundwater. What does 5tar+nwater Runoff have to da with Water G>~uality? Stnrmwater 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 starmwater can reach nearby waterways where i# 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, starmwater is recognized as a major threat to water qua{ity. Remember to keep everything out of starmwater systems except the rainwater they are designed to collect. Your Stnrmwater Facility Different types of ponds are designed for different purposes. For example, wet ponds primarily provide treatment of starmwater. Dry ponds ar detention ponds are designed to provide storage far starmwater and allow far its gradual release downs#ream or into the ground. Who 'ss Responsible for Maintaining Stnrmwater Facilities? A!I starmwater facilities require maintenance. Regular maintenance ensures proper functioning and preserves visual appeal. This Stnrmwater Facility Maintenance Guide was designed to explain how starmwater facilities work and provide user-friendly, straightforward guidance an facility maintenance. You are responsible for regularly maintaining privately awned ponds, catch basins, pipes and other drainage facilities on your property. Starmwater facilities located in public rights-of-way are maintained by local governments. DEL'S FARM 5llPPLY -------- f 01.23.208 PAGE i7 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 mare routine needs of your facility. Included in This Guide ^ Comprehensive Maintenance Checklists that provide specific details on required maintenance. ^ Poilutian 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 The Cities of Lacey, Olympia and Tumwater together with Thurston County are taking steps to educate and involve area residents in water quality issues and stormwater management. stormwater runo#f is a widespread cause of water quality impairment and stream degradation. The jurisdictions are working together with residents, businesses, Community groups and schools to address this problem. This guide fetuses on providing information on ways that you can reduce stormwater impacts through pollution prevention and proper facility maintenance. YDUR ST~RMWATER 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 #acility key far the feature type and checklist name. FACILITY KEY The s#ormwater facility in your neighborhood is comprised of the following elements: ..:. Type of Feature & CheckNst Name Location on 5il:+s` F?lan Ponds ~ Catch Basins, Manholes, and Inlets ~ Conveyance Pipes, ditches, and Swales 3 Grounds and Landscaping ~ DEL'S FARI+IE SUPPLY 01.23.2008 PAGE 18 ss ~'3Te^1:; `~~.'~~~ iy aeza .. me -d sesxs eon.--r~_c -. _._ El~t"3c&'3l.6S ;~~ ,L~ - vn L6Sf36 °i/A~l `W"I3A T~ - 3 Ya :. ~ A l~ a' 8~N ~ P L - ~b'6 :3 i 9C7 } ~~z ~ ~„~ t~ satin inai e.. ~ ~vaan~ .a*~~ 3S El t3 "7'I!N Q ~~ ~ ~ u ~u ~v~~~,~.,~_ ~ ,vim, 0 a ~. ~ z,_ r ~ W ~hw r h -~~ ~"- r. ~l r ~Ff I~ 1 I, 0 ~aa 1 „ ;t ~~ ~ n ~~ ~ M 4~3 L z ~ ~ C ~ ~ ~ 's , F ~ ~ ~ ~ r. 5~ r~~~~y~ ~~"~zx aa'S~ ~ z 4 ^~ WC~'~. z'~ ~ZZ ~ ~~ s'S 'S ~~ ~~ ~ ~ , . a ra m ~ a x ~ r ! j i fi .,, ~ I ui ~ >~ ~ ? ~ ~ ~~ ~ ~~ ~ ( 5 gk; ~ ~ ~ ~ ~~ f a F ~+~ $ ~}+yi~' ~ ~~~ s,y k ~ I ~ # ~ Y 3 m 5ia &i i5f a~~6`if 'i °5 P5 'Sn tb 5 a t5n E e a' a s~ u ya n LG C`i Y, u. ~ Z .~ ¢ 1°- a O Q G~. G2 `._'a~C. a~1~o.n as ~. ~ w ~ ~ ®p ~ t ~ ~ 0. W ~ ut ipw w:-rua g j OaR' W ~QMi~'>~ aaC per.. ',. ~) eul Ot72`VAODU3m S''~'uz ~, s I ~I I M `Li o ~ ~e h 11 r W~ ~ tr w ~ K ~' ~ ~ ' ''i .- _ , l i _. _ _ -- ~" .. _- ` - - _ - _ - -- - - 1-=-°~ - -- -~ -- ~ '~ --_ -- 7---- --- - - .. - - _- r g I ~~~F3'a ~ } .y c J ~~ a. ~ _ ~~ a w a ~ i ~ ~} a ~ ~~, /` r z 1 t i ~ 3 -_ i n =- 1 ~ _, ~ 1 , - , - ; ~ ~ /,~'r k -, ~ - ,: ._ ~ - ~ r ~ ~ ~~ ' ~- ~~ 'a a~ - r ~ -- ~ ~ ' _ ~ r f E~~ • a ~~ v d 111 ~- __-~ - ~ ~ I ~ ~ ~., - _ ~~ i ~'~-~ ~~ l~ 1 .. ~~`°~ .. 111 ~~~t ~ f ( i , 't . ~ " ~ ~ '~ ! ~- ~ 1 5 / C 8 fi f c ~ j : Fk 3 6 `~ 1~3n /` I 31 7 ~ C $g~ Y a ~5 1. ~~5. ~y 1 "~ ~ ~ l; ~q R I ~ t ~a j i ~P f ~ ~( i °6 u ~ n P i ~I~ ( ~i~„ ~ , 9 ~ ~ffl ~ , ia~o~ r - la J~~~ ~ ~ ~~ ~ 1 ~ ~~ ~{ f - ~,_ ~~ 1 ~ ~' ~ F m ~~ J~ ~ °~ - 1 .,~ ~' ~~ ---- ~~ a d ° ..a n~ ~ ~ r o ~~ ~ ~y 1 d. `` J c~vlclc t_lsT The fallowing is an abbreviated checklist of the most common types of maintenance required. Please g^ over this checklist after heavy rains. The list represents minimum maintenance to be perfom7ed and should be completed in conjunction with the other checklists far an effective maintenance program- ^ 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 if it is broken. ^ Inspect inlet and outlet pipes for blockages. Clear aA blockages. ^ Inspect filter strip, Swale and pond walls for erasion ar caved in areas. ^ Inspect riprap [racks] at the inlets and outlets of culverts and other pipes. If they are silted in or eroded away, replace them. EEL'S FARM SUPPLY 01232Q08 -------------_ _ PAGE 20 MAINTENANCE CHECKLISTS The Maintenance Checklists in this packet are for your use when inspecting the stormwater facilities an your property. This packet has been customized sa that only the checklists for your facilities 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 far ease of use. Each describes the area to inspect, inspection frequency, what to look for, and what action to take. A lag 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 main#enance 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. ^ 5ome kind of pry bar or lifting #ool for pulling manhole and grate covers. ^ Gloves. A resource list is included in the next chapter. Here you will find the phone numbers of the agencies referred to in the tables, as well as the contractors and consultants who designed and constructed your facilities. 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 confined spaces. NO PART ~F YOUR BQDY SN~ULD BREAK THE PLANE OF THE OPEN HOLE. EEL'S FARf~R SllPPLY 01.23.7.Qfl8 PAGE 21 Ponds There are essentially three kinds of ponds: treatmen# ponds, infiltration ponds and detention ponds_ Although each pond has unique maintenance requirements, there are also many things they have in common. Your facilit is a detention ond. Inspection Frequency Look For Action Area Entire Rand Quarterly Yard waste such as grass Remove trash and debris and clippings and branches in dispose a# properly. basin; presence of glass, plastic, metal, foam or coated paper. Entire Panel Quarterly Vegetation that may constitute Remove invasive or noxious a public hazard, e.g., tansy vegetation. Do not spray ragwort, poison oak, stinging chemicals an vegetation nettles, devilsclub. without obtaining guidance from WSU Cooperative Extension and approval from City or County. Entire Pond Quarterly Presence of chemicals {e_g., First, attempt to locate source naturaE gas, ail or gasoline}, of pollution; then call Moderate noxious odor or sludge. Risk Waste program at Thurston County Environmental Health to report the hazard. Entire Pond Quarterly Sparse, weedy or overgrown Grassy ponds: selectively grass in grassy (drylinfiltration} thatch, aerate and re-seed ponds; presence of invasive ponds. Grass should be kept species or sparse growth of less than 8 inches high. Wet plants in wet panels. ponds: hand-plant nursery- grown wetland plants in bare areas. Contact WSU Cooperative Extension for guidance on invasive species. Pond bottoms should have uniform dense coverage of desired plant species_ Entire Pond Quarterly Evidence of rodent holes if ^estroy rodents and repair facility is a dam or bean. Water dam ar berm. Contact should not flow through rodent Thurston County Health hales. Clepartrnent far guidance. Entire Panel Quarterly Nuisance insects such as []estroy or remove insects. wasps, hornets or mosquitoes Contact WSU Cooperative that may interfere with Extension far guidance. maintenance. Checklist continues on next page_ pEL'S FARM SUPPLY ~1,23.~008 PAGE 22 Ponds Checklist, Continued ,: ; . cY..:: Fre uen > ;.:... . ....: t.ook;lFor : ~: : ` 'Aetini Area :. z . : Entire Pond Annually Confirmation that trees are not Prune tree limbs to allow far interfering with maintenance maintenance. Some trees [i.e., mowing, silt removal or may be cut. access}. Inlet Annually Confirmation that the riprap Replace rocks andlor remove under the inlet pipe is intact sediment. and that na native soil is exposed. Also, soak far accumulations of sediment greater than half the height of the racks. ^utlet Quarterly Afree-flowing overflow that is Replace riprap if missing. clear of debris. Remove #rash ar debris and dispose of properly. Side Slopes Annually Signs of erosion around insets Attempt fa determine the and ^utiets. Inspec# berms for cause of erasion and repair it. signs of sliding or settling. Stabilize slopes by reinforcing Take action if eroded damage with rock, planting grass, or is over 2 inches deep and compacting soil. Contact where there is potential for WSU Cooperative Extension continued erosion. for guidance an slope reinforcement. Storage Area Annually Sediment build-up an pond Remove the sediment and re- bottom. A buried or partially seed the pond if necessary to buried outlet structure or very improve infiltration and control straw infiltration rate may erosion. indicate significant sediment deposits. Dikes Annually Significant settling of any part Build dike back to the original of dike. elevation. Emergency Annually Intact riprap protective area- Replace rocks sv all native soil ~verflowl Repair if any native soil is is covered. Spillway expvsed_ Trench Drain Quarterly Confirmation that the grate is Remove debris from grate, clear of debris and that the clean drain. drain is not plugged. E]EL'S EAftM SUPPLY a1-23-2~Q8 PAGE 23 Catch Basins, Manholes and Inlets These structures are typically {orated in the streets and public rights--of-way. Local jurisdictions are responsible far routine maintenance of the pipes and catch basins in rights-of--way, whereas homeowners are responsible for keeping the grates clear of debris in all areas as well as pipes and catch basins in private areas ..... Inspection ~~:, : .. iFr~egency ; ~:' ~.isak For coon ~.. .:A ,.. tea ;. ,.... Catch Basin During and Accumulation of trash or debris in front Remove blocking trash or ^pening after major of catch basin opening that prevents debris with a rake and storms water from flawing in. clean off the grate. Catch basin Quarterly Sediment or debris in the basin. No Remove debris from more than half the depth from the catch basin. bottom of the pipe to the bottom of the basin should be allowed to accumulate. Use a fang stick or broom handle to poke into sediment and determine depth. inlet and Quarterly Trash or debris in the pipes that has Remove trash ^r debris Dutlet Pipes exceeded 115 of their height. Ensure from inlet and outlet there are not tree roots or other pipes. vegetation growing in the pipes. Inlet and Annually Cracks wider than '/:inch and longer Repair cracks or replace cutlet Pipe than 12 inches at the joint of any inlet the joints. Joints or outlet pipe. Also check for evidence of sediment en#ering the catch basin through cracks. Grate Quarterly Cracks longer than 2 inches or Replace gra#e if multiple tracks. necessary. Frame Quarterly Confirms#ion that the frame is sitting Repair or replace the flush on tap of the concrete structure frame so it is flush with [siaby. A separation of mare than ~/ the slab. inch between the frame and the slab should be corrected. Catch Basin Annually Cracks wider than % inch and longer Replace or repair the than 3 feet. Alsa Check #or any basin. Contact a evidence of sediment entering the professional engineer for catch basin through cracks. evaluation. Determine whether or nat the structure is sound. Checklist continues on next page. DEL'S FARNf SUPPLY ~1232flflg PAGE 24 Catch Basins, Manholes and Inlets Checklist, Continued ,.. Inspection Area ~~t'equency >, Laok i'nr : ~Actian Catch Basin Quarterly Chemicals such as natural Clean nut catch basin. Contact our y gas, oil and gasoline} that local jurisdiction ar Thurston County may have en#ered the catch Environmental Health if you detect a basin. Check far noxious color, odor or oily sludge. odor or oily sludge. CillWater Quarterly Significan# sludge, ^il, Remove the catch basin lid and skim Separator grease or scum layer off oil layer. Pour ail into a ~downturned covering all or most of the disposable container, seal container, elbow nr "T° in water sur#ace. wrap securely in newspaper, and Cathh Basin} place it in the trash. Water surface should be clear of oily layer. Pipe Elbow Quarterly Damage to top or bottom of If pipe is broken, replace pipe in pipe; determine whether accordanoe with approved plans an pipe is plumb. file with your local jurisdiction. DEL'S FAR[+11 SUPPLY 01.23.~(la8 PAGE 25 Conveyance Pipes, Ditches and Swales Inspection .; . . ~ Frequency: F':~: Look Fa[;. .. Action - ;: . Area Pipes Annually Confirmation that accumulated Clean pipes of all sediment sediment has not exceeded and debris. Remove all 20°/° of the diameter of the pipe vegetation sa that water flaws and that vegetation has not freely through pipes. Repair reduced free movement of or replace pipe as necessary. water through pipes. Ensure that the protective coating is not damaged and rusted. ^ents should not significantly impede flow. Pipe should not have major cracks or tears allowing water to leak out. Dpen ^itches Quarterly Yard waste or litter in the ditch, Remove trash and debris and dispose of properly. Dpen Ditches Annually Confirmation that accumulated Clean ditch of all sediment and sediment has not exceeded debris. 2fl°/° of the depth of the ditch. ^pen Ditches Annually Vegetation [e.g., weedy shrubs Clear blocking vegetation s^ and Swales ar saplings] that reduces the that water flows freely through free movement of water ditches. Grassy vegetation through ditches or Swales. should be left alone. Dpen ^itches quarterly Signs of erosion. Inspect Eliminate causes of erosion. and Swales slopes for signs of sloughing or Stabilize slopes by using settling. Action is needed appropriate erosion control where eroded damage is over 2 measures [e.g., reinforce with inches deep and where rack, plant grass, compact potential for continued erasion soil}. exists. Dpen Ditches Annually Adequate rock placement in Replace rocks to design and Swales splash pad, check dam or standard. lining. Native sail should not be visible. Swales Quarterly Adequate grass coverage. Aerate sails, reseed and lake action if coverage is mulch bare areas. Keep grass sparse and weedy, or areas are less than 8 inches high. overgrown with woody Remove woody growths, vegetation. regrade and reseed as necessary. Swales Quarterly Confirmation that Swale has not I# possible, speak with been filled in ar blacked by homeowner and request that structures, shrubbery, etc. the Swale area be resfored. Swales Annually Standing water in Swale or very A survey may be needed to slow flow velocity. Stagnation. verify grades. Grades should foe between 1 °I° and 5 °/o. r3EL'S FARIV~ SUPPLY 0123.2Q08 PAGE 2fi Grounds and Landscaping I.nspectirin~,: n:: ]I Frequen ..:L olc For .::.- :. ~.:: ,.:. Q ....: ....:.:~s ::~.. . Action '.aF~~`°:: . :::~z;: ... ..::::.,Area ~.:: :;.:.: . _ . ~`: Landscaped Quarterly Uncontrolled weed growth in If possible, pul[ weeds by hand to Areas landscaped areas. avoid using chemical weed controls. Landscaped Quarterly Presence of poison ivy or Remove poisonous vegetation or Areas other poisonous vegetation or insect nests. insect nests. Landscaped Quarterly Yard was#e or litter. Remove and dispose of properly. Areas Landscaped Quarterly Noticeably visible rills in Identify the causes of erasion and Areas landscaped areas. take steps to slow down ^r disperse the water. Fill in contour; seed area. Trees and Annually Split, broken ^r otherwise Trim trees and shrubs to restore Shrubs damaged tree parts and shape. Replace severely shrubs. damaged trees and shrubs. Trees and Annually Blown down or knocked aver Replant trees or shrubs, Shrubs trees or shrubs. inspecting for injury to stem or roots. Replace if severely damaged. Trees and Annually Exposed roots, inadequate Place stakes and rubber-coated Shrubs suppor#, severe leaning. ties around young treeslshrub5 for support. E7EL'S FRRM SUPPLY 01.23.2908 PAGE 27 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: Yelm Public Works (360 458-3244 WSLJ Caaperati~e Extension {3fi0] 786-5445 Engineers Information: HATT~ N GO SAT PANT] ER 1840 Barnes Blvd 5W Tumwater, WA 98512 (360} 943 -1599 DEL'S FARM SUPPLY 81232008 PAGE 28 LOG SHEET E?EL'S FARM Sf~PPLY 01.~3.2~08 PAGE 29 Use log sheets to track maintenance checks and what items, if any, are repaired or altered. The completed sheets wilt 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. 111. P~LLUTIDN Snl1RCE CONTRC]L PROGRAIVI What Are Pollution Source Controls and Why Are They Needed? Pollution source controls are actions taken 6y a person ^r business to reduce the amount of pollution reaching surface and ground waters. Controls, also called "best management practices" {BMPs} include: ~ AI#ering the activity {e.g., substi#ute non-toxic products, recycle used ^il, route floor drains to sanitary sewer rather than storm sewer}. s Enclosing or covering the activity {e.g., building a roof}. N Segregating the activity {e.g., diverting runoff away from an area that is contaminated} E Routing runoff from the activity to a treatment alternative {e_g., a wastewater treatment facility, sanitary sewer, or stormwater trey#ment area}. Pollution source controls are needed because of the contamination found in runoff from commercial areas and the effect of this contamination on aquatic life and human health. Research on urban runoff in the Puget Sound area and elsewhere has found oil and grease, nutrients, organic substances, toxic metals, bacteria, viruses, and sediments at unacceptable levels. Effects of contaminated runoff include closure of shellfish harvesting areas and swimming areas, mortality of young fish and other aquatic organisms, tumors on 1"rsh, and impairment of fsh reproduction. Materials Used and Wastes Generated Of particular concern are drives and parking areas. Because of heavy vehicle usage, the concentration of oil and grease in stormwater may exceed the Ecology guidelines of 10 mg11. Although there are no local data to confirm this view, limited research in the San Francisco Bay area found the mean concentration of ail and grease in stormwater to exceed 1g mg11. Required Actions The following actions shall be taken to ensure that pollution generated an site shall be minimized: 1. Warning signs {e.g., "Dump No Waste -Drains to Stream"} shall be painted ar embossed on or adjacent to a!I storm drain inlets. They shall be repainted as needed. Materials needed to undertake this task can be purchased or may be available from the Public Involvement Coordinator for the Department of Public Works. 2. Sediment removed from basins, pflnds, and swaies shall be disposed of in a proper manner. Contact the local governing jurisdiction for inspection prior to completing this task. 3. No activities shall be conducted an site that are likely to result in short-term, highly concen#rated discharge of pollution to the stormwater system. Such activities may include, but are not limited to, heavy vehicle maintenance, and cleaning of equipment used in the periodic maintenance of buildings and paved surfaces. 4. Use of pesticides and fertilizers shall be minimized. 5. Da not dump paint, solvents, oils, ^r other such substances, including landscape waste, into s#arm drains ^r ponds. DEL'S FAF2M SUPPLY --- p~.23.2Qb8 PAGE 30 APPENaIX A -Site Pian EEL'S FARM SI~PPLY fl1.23.~0~8 PAGE 31 ~~ ~x ~,~~ ~ ,~~ -- - es tad ~~as ~ .- ~' ~ ~ ~ y I N c~sae ~rrt`w-s~sR. I :`~ ..~ ~ =, saona~ans r~n. aaarve~~r~a 3a O~6 -t-7[4-i i71b'~ 9 [ 0t3 € .. ___--_ ~~~ m '' ' .. , ~131L!'.tR1c4 !`J4~1_~'d!-i- ,~'~'r~s3~1S 6~`VIa~S~~ ~i~4`~C3 -~- ...n_,~a ~u QOLQPZf9£P~#cs1 `~ ~c »~.n.-~-.~ ~ .. h` I di ~,, ~~ ~~ ~ ~ ~' t ~ ~ ~ ~ t ~ W a e ~ s ~~~ ~~ ~ ~ ~ ~ x + ~~ _ U ~ x ~ ~ II ~'~ ~ ~ ~mn ~aa~ w x ~ JI{ { i ~~ ~ i ~i Y ~ ~ 5 ~ Y ~ ~ ~ T ~ ~ ~ ~ ~' N ~~ kY gg ~ k ~ ~ ~ 2 ' ~ ~ ~ ' ~ '~ K ~ ~ ~ r Y y R ~ ~x1S~ fr ok i ~''t i.;r~~i. 'G 5L `fro. ~i ~ws.aW~c:~rs ~a~~. s~~ 's-~ss c~~rn :. ;s ~~--~I I ua ~ ~`r- °, A 2 ~ ~ u -4 dd 4 ~ ~ Q tit-- ffifl~-J Sa aS. ES= x ¢ ¢ ¢ 5K' WCe~~ H4-H ZQ 2';K2 o m ~ ~ ~ fCp~Zgy~j~¢tY p: fC EC W in1 "a4[}~^SLL1 W 4u W tyy p.. ?6~ K~ W "y F.H4°. W ^wct c3 a3wOL'ww ~~+n ~ vnvu'sws= o ° = "" f I ~ ~ i ~ ai s ~ r -~~ `' i ~~ ~5 ' * ~ ~ ~ ~ ~ ~ ~e ra j oil ~~w ~ ~~~ €~~'a. ~, ~"2 ~~ vw ~° ~ `~ ~r 4 i ser ~ ~~ s 9 a T~~ ~ac ~ aid ,~ ~ ~ ~ ~ ~ r ~, ~ s I, ~~~ I w~h' ~ ~ ~ 5 ~ § ~~e ~ ~ - a r ~;. ~ Y-~ J y s ~~.~ s, li s a '~ ~ r-3 ~ e~ -?,fie ~~ ~ ~-~ ~ ~ 'i ._ ~~~ ~ ~ ~ ~ ~ I , . . _;_ __ _ _ - -- - t - - --- - - 'c -- - _ A - I T _ - ~" ~ i ~, ~ LL 3~ p. ~ A I ~ ~ I - _ +. ,a ~ J - ~~ -, e ~ w o M i l i cau -- i j i ~ I .~ - _. -- -- - - I ~~< 1 ~-°`s' . _ i '` ~~ i ~ ~ ..r---- l' ~~:~ ' i_ - _~ - ,, ,, ` ~ ~ t "' ~_ ,~ r - ~ e r ~~ ~I~ ~ - I ~ ~` ~. ~ L_ -' A ~ ~ u I ~' I~ ~° ~ 11 a r, ~ "~ ~ `~ ~ i ~, ~'! ~('( ~~~ " ~%°, k s 3 'o ~ Y \i ~ X ~i, ~ 3 Cs as q __. ~ ~ /i N *Tf / ?/ I ~ x~. r~/ _ (~ ~ ' ~ ~ `2 ~ o ~ ~ `~ ~~~ - 1 ~~ d 'S. I 5'~ ~ ~ j ~ ~ ~ % "~\ ~' f~ ya " / ~ ...:~ ~ / ~r ... tJ O I ~ ~ {.{ ' ~I ag ~ ~W ~ r yy~ ~ ~ h p ~ i ~ ~ W 5~L Z) ~ ~ F fr y+ X 4 _ x`~. ~r 5r ~ ~. U t ' ao ~ ~J ~ 4 ~ m ~ ~A J iJ s i Q Y 4 .-._ -- __- _ d T ~ ~ ~ ~ d ~ ~ ; W ~ ~~~ C v~ ~ ~ e~q r~~€~ ~ E ~ E ~ ~ W . ~~ W C ~ ~ W r E ~ ° ~ ac '. d ~ ~ i ~ ~ '_~ ~ ~ i ~ .a W ~ ~ ~ W ~ ~ ~ ~ : E E ~20 5~ ~ v G~ ~ o Q a~ , 66 ~$ ~_ X _ ~ ~ ~ E` ~ ~ ~ era ~ 1 ~ ~' ~~g ~ {Q R~p yy E y N ~ a O. V7 ~i ~ ~ C"~ F W i ~ x + ~ ~" i iiS $ BYE~F E Z .. ~ ,,,., ~ co r ?c ~ ~ ~ E _ w p s _ie r G ~ J .'7 ~ x ~~~ W i x W `~ ~ W t A_' ~~ E_~ ~~~~ ® ~~A~ i•~a C1 r z Y °~ W c~F ~ ecz vz ~a ^ ~Q s i~ a [] N a ~ ~ ~ as -' N orou, aoo7 uan c ~ I ~ ~ , .C, ~ %J ~ T2 ~ ' ~~ 04 • O ' o ~~ ' ~ . s _ ~ _ ~ o00 • ~4 . a . j a - .n n ° `cam -' om` v ~7 ~ • 1l `" vo 6v d o .^ ae .at a i'] i~7 ~ + 17 2 2~ Da ~~~ + c v o. °op 0 fl 7! J7 ~~P . ~ 7 Q_ ~ [~ ~' oP 3 P G ~ f ] P , S C.7 ' 9 ~ . ~ i 3 JJ l Y ~ O ~ ~ / / / ~ 11 71 eP •• ' I ~ ` ]'~ f ~S ~ ~? ~ E.' N '' _ w w ~ ~~ LL V % ~ ~ W o, a ~ r Y i~ s ~m w , z ~ w ~ a~ a A ; ~ ~ ^ T`~ y yO ~ ° o Q 6~ r, ,, ~ o ~ V o-. ~ p 4 N ti iy ~ ~ ~~ z .o `' ~ a J ° ~ . .... - . ~ .. , Sfax n ~ kaal. '] rr a' o- ~ n ~ . ~ E y•• c ; ~ Q ~ ~ U ^ N w ? isvarainvs ' oroa ~ ~a uow e o o , . r ,~/ II A Uw V~ ~ _ p ~ ~ - ma ~, 'z c p ~ o t I ~ ~ 1 a ~ z $ _ ~ r. ~ ~ ; ~ a ~a = - = ~, i o W ~ _ ~ L N Y $ ~ m ~ ~ ~ ~ ~ • w, °"O 9 ~ • • v o ~ ~ W a ~_ e K a ~~ v - ["~ ^boa .a ~aa+~~ • o ~~~ ~ ~ ~ ~ a ~~ m ~ ~ ii _ ~ w n ~~ ~ '~ r c u ¢ W ° i N ^ 1 ~ 2 ~ gm _ Z •f ~n H . ~r • 9 ~ ~ ' _. ~ a z qa o ~ ~~ w W ~ ~~ z a ~~ -- APPENDIX B -Calculations EEL'S FARM SUPPLY 01.23.7.QQ8 PAGE 32 7i.0 .-. 1A e1 ... o Predeve ed L ~~_~ Kxx Mitigate ea _~ ~ akkk~~~` ~ 0 k~$~~~ x 10E-2 1 1a 2a 3Q 4a5osa ~a sa 9a 99 Cumufati-re Probaf~fifty Yearly Peaks for Prede-relvped Flew Frequency Chart YEAR FLOW Msl 100 ,~ ~ ~ a Predeueloped 50 .8319 x Dsv~elaped with Facility .~ .TT~1 0.15 - _-- - ~1a .6933 .-. +~ 0.71 -- _..~ ------. _- 3 .6261 R] ..K ~ 0.07 ..~.._ _.._.__.._._r 2 S1T4 L, y a.oa ~, ~ 10E-5310E-A 1QE~ t11f=-2 !OE•'I 1 'Ea Percent Exeeedin Yearly Peaks fnr de~elvped W10 Pond ^uration Graph YEAR ROW [~ 100 .2x44 ~0 .1T29 25 .1440 10 .1093 5 .050 2 A535 Yearly Peaks for Developed WlPond WESTERN WASHINGTON HYDROLpGY MODEL V2 PROJECT REPORT Project Name: fly-855 dels final Site Address: City Yelm Report Date 09/05/2007 Gage Olympia Data. Start 1955 Data Er~d 1999 {adjusted Precip Scale: 0.80 PREDEVELC]PEn LAND USE Basin Basin 1 Flows To Point of Compliance Groundwater.:_ ~In WESTERN WASHINGTON HYDRpLQGY DEL V2 PROJECT REPORT Project Name: 05--855 dels final Site Address: City Yelm Report Date 09/06/2087 Gage Olympia Data Start 1955 I]ata End 19 9 9 {adjusted} Precip Scale: 0.8[3 PREDEVELOPED LANID USE Basin Basin 1 Flows To Point of Compliance Groundwater: IVo Land Use Acres TILL FOREST: 2.18 Basin Basin 2 Flows To Point of Compliance Groundwater: Igo Land [Ise Acres TILL EY]RLST: 8.41 DEVEIAPED LAND USE Basin Basin 1 Flows To Pend 1 Groundwater: No Land Use Acres OUTWASii PASTURE: 0.41 IMPERVIOUS : 1. `7 7 Basin Basin 2 Side s 7.ope 2 : 3 Ta Side slope 3: 3 To 1 aide slags 4: 3 Ta 1 +~alume at Riser Head: 0.9D9 acre-ft. Dischar a Structure Riser Height: 3 ft. ~Ziser I]iameter : 18 in . NotChType _ Rectangular Hatch Width D.040 ft. Notch Height: 1.169 ft. Orifioe 1 Iliakneter: 1. DD1 in. Eievatian: D ft. Porxd Hydraulic enable 3 [ft) Area {acr} Valvm~e [acr-ft) Dschr [cfs} Ixifilt [ePa} D.oa^ 6.257 o.oDD D.DDO o.ooD o.aa4 x.258 b.o11 a.oo6 o.DO6 0.089 0.259 D.D23 6.D08 Q.D00 D.133 D.261 0.034 6.O1D O.DOD 0.178 ^.262 D.D45 O.OlI ^.600 0.222 0.253 O.D58 0.012 O.OOD 0.267 0.255 0.07^ 0.014 0.000 0.321 0.7_65 6.081 O.D15 o.aoo 0.355 0.267 D.D93 D.616 O.D60 o.4ao a.zs9 o.1D5 0.617 D.DOo D.444 0.270 0.117 D.D18 0.06D 6.4$9 o.z71 0.129 D.DIB 6.06D 0.533 6.273 D.141 D.D19 D.600 0.578 0.274 0.153 0.020 D.OOD 0.622 0.275 0.165 0.021 O.OOD 0.667 0.277 D_178 0.021 O.DOD 0.711 D.278 0.196 0.022 0.000 D.756 D.279 0.202 6.623 6.oDD 0,800 D.281 0.215 ^.624 O.D00 0.844 0.282 0.227 D.024 O.ODD D.889 D.283 0.246 D.025 0.60D 0.933 0.285 0.253 D.625 D.OOD 0.978 0.286 0.265 0.626 6.OD0 1.D22 0.287 D.278 0.027 0.000 1.667 0.289 D.291 0.027 D.D00 1.111 D.29D 0.304 6.028 0.6DD 1.155 13.291 0.317 O.D28 O.OOD 1.20D 0.293 D.33D D.029 D.00^ 1.244 D.294 D.343 D.D29 D.600 1.289 0.296 0.356 ^.D30 O.OOD 1.333 0.297 6.369 0.030 D.000 1.378 0.29$ 0.352 0.031 DODO 1.422 0.30D 0.385 0.031 O.ODD 1.467 D.3D1 0.4x9 6.632 D ODO 1.511 D.303 D.422 0.032 6.000 1.556 6.304 0.436 0.033 ^.DOD 1.5D0 ^.305 ^.449 0.033 0.000 1.694 0.3D7 ^.A53 D.034 0.006 1.689 0.308 0.476 0.034 0.000 1.733 0.310 0.490 0.035 6.D00 1.778 D.311 0.564 ^.035 ^.DDD 1.822 0.313 ^.518 0.035 O.D60 1.867 0.314 0.532 0.037 6.OD0 1.911 0.315 4.546 6.639 D ODO 1.956 0.317 D_566 6.642 6.OD0 2.D06 D.318 D.574 0.046 0.000 2.D44 0.32D 4.588 0.050 0.000 2.0$9 6.321 0.602 6.054 o.DOo 2.133 D.323 0.617 x.659 0.000 2.178 6.324 x.631 0.064 6.OD0 2,222 D_326 0.645 D_069 0.000 2.257 D.327 0.560 0.074 0.000 2.311 0.328 0.675 0.08D 0.066 2.356 0.33D 0.689 D.085 D.OOD 2.400 6.331 0.704 O.D91 Q.D00 2.444 0.333 0.719 0.09'1 O.DOD 2.489 D.334 0.733 0.103 6.0D6 2.533 6.336 0."748 D.1D9 0.000 ~ ~~R n ~~~ n 7F~ n ~~~ n nnn 2.622 0.339 0.778 0.121 0.000 2.657 0.340 D.793 0.17.] 0.000 2.711 0.342 x.809 0.133 b.000 2.756 0.343 0.824 D.139 0.040 2.800 0.345 0.839 0.145 0.000 2.844 0.346 0.859 x.15Z p_OOD 7...889 0.348 ^.870 0.159 0.000 2.933 x.349 0.885 0.16'1 b.oba 2..978 0.351 0.901 0.].75 D. oxx 3.02? 0.352 0.917 0.227 x.000 3.06'7 0.354 0.932 0.431 x.ODO 3.111 0.355 x.948 0.721 0.040 3.156 0.357 0.969 1.076 x.000 3.200 0.358 0.980 1.487 0.000 3.244 0.36D 0.996 1.946 {3.000 3.289 x.361 1.012 2.449 D.bbb 3.333 0.363 1.028 2.953 D.DDb 3.378 0.365 1.D44 3.574 0.000 3.422 0.356 1.D60 4.19^ 0.000 3.467 0.368 1.077 4.839 0.000 3.511 D.369 1,093 5.520 O.Opx 3.556 0.371 1.1x9 6.232 O.Oxx 3.6D0 0.372 1.126 6.973 0.000 3.644 D.374 1.142 7.741 0.x00 3.689 0.375 1.159 8.536 x.000 3.733 0.377 1.176 9.358 0.000 3.778 x.379 1.193 1a.2p D 000 3.822 0.38D 1.2x9 11.08 ^.b00 3.867 0.382 1.226 11.97 O.b00 3.911 0.383 1.243 12.89 0.000 3.956 0.385 1.260 13.83 O.ObD 4.ObD 0.386 1.278 14.79 D.DDb Flow Frequency Return Period 2 year 5 year 1^ year 25 year 50 year 10^ year Flow Frequency Return Return Period 2 year 5 year 10 year 25 year 50 year 100 year Flow Frequency Return Period 2 year 5 year 10 year 25 year 50 year 100 year AISAT,YSIS RESULTS Return Periods fox Flow [cfs) 0.071268 x.111756 x.1370D5 0.1664b2 0.1$6565 0.2[35152 Periods far Flow [cfs} 0.517409 0.626146 0.693269 D.774x42 b.831898 x.888158 Return Periods for Flow [cfs} 0.053528 0.084953 0.109264 ^.144025 0.1729x9 0.2x4405 Predevelaped Developed Unmitigated Developed Mitigated Yearly Peaks for Predevelaped and Developed-Mitigated Year Predevelo ed Devel.o ed 1956 O.D94 0.059 1957 x.147 O.a46 1958 0.041 x.029 1959 0.048 0.058 ].960 0.109 D.X36 1961 0.477 0.068 1952 0. D24 C7. ^29 1953 0.124 4.089 1954 0.p81 b.a59 1965 D.078 b.035 1965 fl.037 ^.433 195'] fl_©88 O.D59 1.968 O.b64 0.031 1969 0.029 0.031 197D D.069 4.077 1971 0.091. b.085 1972 D.142 b.131 1973 D.D59 D.1D5 1974 D.057. 0.059 1975 4.039 Q.031 1975 b.1D0 O.p89 1977 b.b11 D.D26 1978 b.070 D.075 1979 p.p64 0.029 198D n.p67 0.065 1981 p.p92 a.a51 1982 D.D63 x.057 1983 0.114 0.035 1984 0.083 0.032 1985 0.024 p.p3i 1985 D.14D b. f}75 1987 0.114 p.126 1988 0.041 D.D53 1989 0.051 b.D30 1990 0.142 D.D79 1991 0.187 4.18b 1992 D.p41 b.b35 7.993 p.p29 0.027 1994 D.b29 O.a26 1995 4.D89 p.p62 1996 0.147 p.p83 1997 4.479 fl_08p 1998 0.058 p.p32 1999 0.1D1 p. }_22 Ranked Rank 1 2 3 4 5 5 .l 8 9 10 ]. 1. 12 13 14 15 16 17 18 19 zn 21 22 23 24 25 26 27 28 29 Yearly Peaks for Predeveloped ^.1865 4.1472 0.1469 D.1423 fl.14I9 0.7.397 0.1241 0.1135 0.1142 0.1494 D.1Dp5 O.I003 0.0945 a.0918 p.09a6 O.D887 D.4a7s a.4s3D 0.08D8 D.a789 D.D780 ^.Q770 0.0704 D.4695 0.D591 b.a57D 4.0645 p.n63~ p.D633 Predeveloped and Developed 0.1865 0.1355 0.1314 n.1265 0.1222 0.1046 O.D893 0.0891 0.485D p_0826 0.0799 0.0794 4,0767 4.0751 a.a747 a.069D D.D684 D.D647 b.0522 a.0595 0.059p D.D589 0.057$ D.D568 D.0526 0.0513 0.0455 0.03b1 p_D354 Developed-Mitigated O.b585 0.0357_ 0.0507 0.0326 0.05Df~ 0.0324 O.D479 0.0321 0.0414 0.0314 0.0409 0.0312 0.0407 0.0312 0.0390 0.0307 0.0374 0.0298 O.D293 0.0294 0.0288 0.0294 0,D287 0.0285 0.0.7.41 D.0270 D.0239 Q_0264 D.D113. 0.0261 1/Z 2 year to 50 year Flow{CFSy Prede~ Final Percentage Pass/Fail O.D356 4227 3570 84.0 Pass 0.0372 3892 2974 76.D Pass 0.0387 3589 264? 73.0 Pass 0.04DZ 33D4 2398 72.^ Pass D_D417 3D34 2193 72.0 Pass 0.0433 2780 1996 73..4 Pass 0.0448 2573 1810 70.0 Pass 0.0463 2373 1623 68.0 Fass 0.0478 2173 1486 68.0 Pass D.D494 1994 3356 68.0 Pass 0.05D9 1847 1231 65.0 Pass 0.0524 1709 1115 65.0 Pass ^.0539 1587 10D7 63.0 Pass O.b555 1485 9D9 61.0 Pass 0.057D 1358 8i4 59.b Pass 0.0585 1254 725 57.0 Pass 0.D500 1155 660 57.D Pass O.D615 1063 615 57.0 Pass O.D631 987 547 55.0 Pass 0.0646 913 502 54.0 Pass 0.(3661 847 460 54.0 Pass 0.0676 787 426 54.D Pass D.0692 722 388 53_D Pass 0.07D7 669 360 53.0 Pass O.D722 b21 326 52.0 Pass 0.4737 581 296 50.0 Pass 0.0753 536 264 49.0 Pass 0.0768 505 246 48.0 Pass 0.0783 469 Z33 49.0 Pass D_D798 429 2.24 52.0 Pass 0.0814 3$7 211 54.D Pass 0.0829 360 201 55.D Pass 0.0844 339 185 54.D Pass 0.0859 317 170 53.0 Pass 0.D875 296 16D 54.0 Pass 0.089D 270 146 54.0 Pass ^.0905 255 139 54,Q Pass O.b92D 238 132 55.0 Pass 0.0936 224 13D 58.0 Pass 0.0951 217 123 55.0 Pass 0.0966 200 115 57.D Pass 0.09$1 192 111 57.D Pass 0.0997 180 106 58.^ Pass O.1b12 169 100 59.[3 Pass 0.1027 3.63 99 6D.0 Pass 0.1042 1.55 92 59.D Pass O.1D58 146 89 60.0 Pass 0.1073 134 85 63.0 Pass D.ID88 125 81 64,0 Pass 0,3.103 114 77 67.0 Pass D.1119 108 75 69.0 Pass 0.3134 103 68 6~_0 Pass ^.1149 94 64 68.0 Pass 0.1164 91 59 64.0 Pass D.118D 84 52 6'_.D Pass 0.1195 78 48 61.0 Pass 0.1210 72 42 58.0 Pass 0.125 67 35 52.0 Pass 0.1241 65 33 5D.D Pass D.125fi 58 3I 5:3.0 Pass D.1271 55 25 44.0 Pass D.1?_8fi 51 25 49.0 Pass 0.1302 47 23 48.0 Pass 0.13I7 42 7.$ 42.D Pass 0.1332 37 18 48.0 Pass 0.1397 35 16 44.0 Pass 0.1363 37_ 14 43.0 Pass 0.1378 29 13 44.D Pass ^.1393 26 12 46.D Pass 0.14D8 24 12 5D.D Pass 0.14?.4 20 11 55.0 Pass 0.1439 19 11 57.0 Pass 0.1454 17 11 64.D Pass 0.1469 14 10 71.0 Pass 0.14$5 12 1^ $3.D Pass 0.1500 12 IO 83.0 Pass D_1515 1I 8 72.0 Pass D.I530 10 8 8D.0 Pass D.I545 10 8 80.0 Pass D.1561 1D 7 70.0 Pass D.I576 9 7 77.^ Pass 0.1.591 8 7 87.0 Pass 0.16D6 8 7 87.D Pass 0.1622 7 b 85.0 Pass 0.1637 7 6 85.D Pass 0.1652 6 6 100.0 Pass D.1657 5 S 100.0 Pass D.1683 5 4 80.0 Pass 0.1698 5 4 80.0 Pass 0.1713 4 3 75.D Pass D.1728 4 3 75.D Pass D.1744 4 3 75.D Pass D.1759 3 3 100.D Pass 0.7.774 3 2 66.0 Pass D.1789 3 2 66.0 Pass 0.1805 2 2 100.0 Pass 0.1820 2 2 100.0 Pass 0.1835 1 1 100.0 Pass 0.1850 1 1 100.0 Pass 0.1866 1 D .0 Pass Water quality H1IP Flaw and Volume. an-line facility volume: U.1155 acre-feet pn-line facility target fiox: O.U639 c£a. Adjusted for 15 min: O.U634 ets. off-line facility target flow: 0.0357 cfs. adjusted £ax 15 min: O.R357 cgs. 'this program and accompanying documentation is provided 'as-is' without warranty of any kind. The entire risk regarding the performance and results of this program is assumed by the user. Clear Creek Solutions and the Washington State nepartment of Ecology disclaims all warranties. either expressed or implied, including but not limited to implied warranties of program and accompanying documentation. In no evert shall Clear Creek Solutions andlor the Washington State Department of Ecalagy be liable for any damages whatsoever [including without limitation to damages for loss of business profits, loss of business information, }~usiness interruption, and the like] arising out of the use of, ^r inability to use this program even if Clear Creek solutions or the Washington State nepartment ^f Ecology has been advised of the possibility of such damages. Tra ~zvitlal ~3asi~. Length 65 ft Width 15 ft side slope 1 3 side slope 1 3 side slope 2 3 side slope 2 3 Base ele~atic 290.00 ft Aeq Volume 0.1165 ac ft 5074.74 cf Vol wxxe Elevation cf ac * ft 290.00 0 O.D000 290.50 549 0.0126 291.0D 1224 0.0281 291.50 2D33 OA467 292.p0 2985 0.0685 292.50 4087 OA938 293.40 5348 0.1228 293.10 5620 D.129p 2.93.20 5899 0.1354 293.30 6185 4.1420 293.4D fi477 0.1487 293.50 6776 0.1556