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Home My WebLink AboutO&M ManualBMP OPERATION & MAINTENANCE MANUAL Robbins Subdivision Project Site Addresss: 11400 Westfield Boulevard Carmel, IN 46032 Prepared For: Kevin Silvius 40 E Bloomfield Lane Westfield, IN 46074 08-Mar-2024 Prepared By: William A. Cash 212 Redwood Circle Noblesville, IN 46062 Page 1 of 23 William A. Cash 317-490-4036 TABLE OF CONTENTS 1. Project Narrative 2. Background 3. Inspection Requirements 4. Inspection and Maintenance Activities • Stormwater Management Area • Storm Structure Sumps • Storm Sewer System • Infiltration Trench 5. Owner Acknowledgement 6. Appendices • BMP Location Map • Details o Outlet Sump Structure o Storm Sewer Trench/Pipe o Infiltration Trench • Inspection Checklists o Storm Sewer and Sump Structures o Storm Sewer o Stormwater Management Area Page 2 of 23 William A. Cash 317-490-4036 Project Narrative The Robbins Family plans to subdivide their 4.58 acre at 11400 Westfield Boulevard and construct a three new single family residential homes. The three new homes will be located east of the existing homes and accessed by a common drive. Existing impervious surfaces include a residence, barn and paved areas. The proposed development is on a site located within Clay Township, Hamilton County, Indiana. The site is generally located in Section 1, Township 17 North, and Range 3 East, Hamilton County Indiana. The site will discharge by overland flow and drain directly into an onsite stormwater management area located in the southeast corner of the property. The project will replace an existing residential driveway culvert. Additionally, separate SSD lines extend to the three building pads and are intended to collect roof drainage and convey the flow directly to the stormwater management area. The stormwater management area acts as both a natural BMP and detention pond. The new stormwater management area will be equipped with an outlet control structure and outlet pipe which will drain to Westfield Boulevard right-of-way. Stormwater quality best management practices for this property include sump grass swales, infiltration trench and a “sumped” outlet control structure. BMP Owner Contact Information Kevin Silvius 40 E Bloomfield Lane Westfield, IN 46074 317-610-2627 Page 3 of 23 William A. Cash 317-490-4036 Background Best Management Practices (BMP) - Best Management Practices, refer to structural or non- structural measures designed to improve stormwater quality. Urban stormwater runoff contains pollutants that in high concentration impair the quality of natural streams, rivers and lakes. When compared to stormwater run-off from natural undeveloped areas, concentrated developed runoff contains a high amount of pollutants including petroleum-based products, fertilizers, pesticides and sediments. Poor stormwater quality can be harmful to the environment. Impervious surfaces and stormwater detention ponds increase stormwater temperature and further damages offsite stormwater quality. Stormwater pollution increases biological oxygen demand and reduces oxygen levels available for aquatic organisms. Increased runoff volume and increased flow rate tends to erode and degrade sensitive aquatic habitat. Residential and commercial paved areas introduce pollutants including heavy metals, oils and grease that eventually drain to streams and rivers. BMP Owner - Typically the property owner also owns and maintains the stormwater best management practices. In some arrangements when agreed to by written contract a property lessee could agree to operation and maintenance responsibilities for the site BMPs. Stormwater Infrastructure - Stormwater infrastructure includes piped or lined drainageways and natural drainageways designed to safely and efficiently drain stormwater and protect site improvements. Stormwater results after grassed areas, paved areas and rooftops can no longer absorb or “soak up” stormwater and flow results. Stormwater flow either enters the storm drain system or runs directly into streams, rivers or lakes. The BMP owner typically manages and maintains the stormwater infrastructure. Storm Sewer Pipe – Storm sewers require an annual inspection. It’s best to perform inspections during dryer times of the year. Storm sewer maintenance and repair should also only occur during periods of minimal rainfall. The BMP owner should inspect storm sewer inlets frequently and at a minimum once every six months. When obvious unseen problems exist that reduce the capacity of the storm sewer the BMP owner should televise the system in an effort to identify the obstruction or failure. Signs of obstruction for failure include excessive sediment, erosion of natural channels, visibly failed concrete or plastic piping, pipe or structure settlement. The BMP owner shall create a written report indicating the nature of the failure and the actions taken to restore the system. Page 4 of 23 William A. Cash 317-490-4036 Stormwater Pond - Detention ponds are used to improve the quality of urban runoff from roads, parking lots, residential neighborhoods, commercial areas, and industrial sites, and to reduce peak stormwater runoff rates by providing temporary storage during larger storm events. If the detention pond on your property was constructed early in the development process, it was probably used to trap sediment from construction activities in the tributary drainage area, a very effective way to collect and remove pollutants. In addition, the detention pond on your property may provide other benefits such as open space opportunities in addition to reducing peak runoff rates and improving water quality. A functioning detention pond is a requirement for stormwater management. You, as the owner of this stormwater feature need to understand the importance of the detention pond facility and your obligation to assure its continued proper function. This provided detention pond inspection sheet will provide the information you need to operate a fully functional detention pond on your property. The owner shall establish and maintain a healthy stand of native vegetation which will stabilize the pond area and improve the ponds function. Infiltration Trench – The purpose of the infiltration trench is to promote absorption of the runoff into the upper organic soil layers where natural biological process tend to improve the water quality. The infiltration trench consists of a perforated plastic drain tile wrapped in geo-textile filter cloth and backfilled with washed crushed stone. Both the crushed stone trench and perforated drain tile lead to the pond outlet. Excess site stormwater runoff enters the infiltration trench and pond area. The outlet control structure restricts the flow rate so that the stormwater backs up into the trench and allows for time for percolation. Ultimately, the stormwater recedes and the trench drains down the pond water level so that the owner can access the area and perform maintenance. The perforated plastic drain tile should be inspected and maintained along with the other site drainage pipes installed on the property. Sump Structure - Sump structures collect drainage surface flow and tramp sediment in a portion of the structure lower than the outlet pipe. Sump structures typically include a hood or snout covering the outlet pipe which helps collect sediment and debris in the structure and prevent downstream migration of pollutants. Sump structures require regular removal of sediment from the lower portion of the structure. When sediment collects to a depth level with the outlet pipe the structure will no longer function to remove sediments and downstream pollutant migration will result. Depending on the depth and volume of the sump the owner could remove sediment by manual methods; otherwise, safe maintenance practices require use of a vacuum truck. Page 5 of 23 William A. Cash 317-490-4036 Inspection Requirements The BMP owner shall regularly complete all inspections and perform maintenance and when necessary hire qualified contractors to make significant repairs. The BMP owner shall be financially responsible for any maintenance or repairs required by the City or its representatives during the City’s inspections. The approved maintenance plan and inspection forms provided with this manual should be used as guidance for performing maintenance activities. Completed inspection forms must be maintained by the BMP owner. The BMP owner shall present inspection and maintenance records upon request by the City. The City must be notified of any changes in BMP ownership, major repairs or BMP failure in writing within 30 days. The letter should be addressed to: City of Carmel Engineering Department 1 Civic Square Carmel, IN 46032 The City and/or its representatives have the right to enter the property to inspect BMPs. In the event that the City finds a BMP in need of maintenance or repair, the City will notify the BMP owner of the necessary maintenance or repairs and give the landowner a timeframe for completing the maintenance or repairs. If the maintenance or repairs are not completed within the designated timeframe, the City shall perform the maintenance or repairs and bill the landowner for the actual costs for the work. There are requirements regarding the submittal of annual inspection reports to the City of Carmel Engineering Department. The first report is due one year after construction is completed, with subsequent reports due each year within the same month of the initial report. If there are any deficiencies found during the inspection, these should be addressed. If the inspection report is not received within the month it is due, if there are deficiencies which were not included in the report, or if any deficiencies included in the report are not addressed in a timely manner, the BMP owner faces enforcement action from the City. Page 6 of 23 William A. Cash 317-490-4036 Inspection & Maintenance Activities Refer to the checklists provided with this manual for operation, maintenance and inspection of a BMP and stormwater infrastructure. The checklist is for the use of the BMP owner in performing routine inspections. The City will perform annual inspections of BMPs, using similar checklists when necessary. The BMP owner must maintain and update the BMP operations and maintenance plan as conditions change. At a minimum, the operations and maintenance plan must include, but is not limited to: 1) Visual inspection and removal of debris from inlet, outlet, and sump structure 2) Removal of sediment from stormwater management area and infiltration trench BMP owners must routinely inspect BMPs to verify that all BMP components are functioning as designed and are not in danger of failing. All BMPs require regular maintenance to function properly and efficiently remove sediments and pollutants from stormwater. Maintenance efforts include sediment removal, mowing and repairs to eroded areas. Dry stormwater detention areas should include a permanent and healthy stand of grass. The detention area should be kept free of debris and maintained in such a manner as to encourage native species plant health and limit the growth of noxious weeds. In general, follow these guidelines when maintaining the detention pond vegetation. First year: mow when vegetation is 6 to 12 inches high. Native plants are sending down roots and will be shorter than non-desirable vegetation. It may be necessary to mow several times to keep vegetation below 12 inches. Second year: continue to mow, but less frequently. Third year: native grasses and forbs should be able to hold their own. After three years: plan to burn or mow every third year. The owner shall consult with the nursery providing the plantings on further more specific good practices concerning the prolonged health of the native plantings. Page 7 of 23 William A. Cash 317-490-4036 The BMP owner should limit the use of fertilizers and pesticides within the dry detention area. Storm sewer should be kept clear of sediments and debris. The natural areas near ditch or swale drains should include rip rap or other permanent structures in good repair to avoid introducing soil and sediment into the storm sewer system. The BMP owner agrees to the maintenance and inspection program defined with this manual. The BMP owner shall document inspections on appropriate forms. The site owner shall organize a self-monitoring program construction of the site. A trained individual employed or retained by the site owner shall prepare and maintain written evaluations of the stormwater improvements. Inspections during the post- construction operation and maintenance period must include routine inspection of all stormwater infrastructure to verify that proper functioning of the system. The stormwater system shall be inspected on an annual basis or upon observed failure. The owner and inspection personnel are encouraged to reference the IDEM "Indiana Storm Water Quality Manual" specifically Chapter 8 for additional information and resources pertaining to the operation, inspection, maintenance and repare of post- construction best management practices. https://www.in.gov/idem/stormwater/resources/indiana-storm-water-quality-manual/ Page 8 of 23 William A. Cash 317-490-4036 Owner Acknowledgement Agreement (“Agreement”) For good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the undersigned owner (“Owner”) hereby submits this Operation and Maintenance Manual (“Manual”) to the City of Carmel, Indiana (“City”) as a written acknowledgement of Owner’s warranty and agreement to institute, maintain, and follow the water quality Best Management Practices (“BMPs”) listed below, and to follow and abide by the inspection schedule and maintenance activities listed in this Manual. The Owner also hereby agrees to provide, at Owner’s cost, all additional maintenance, repair, and/or replacement services reasonably necessary to maintain the function and longevity of the BMPs from and including the date this Agreement is executed by Owner to and including the date on which a new Agreement is filed with the City by another party who assumes all of the obligations and responsibilities of Owner as set forth herein. BMPs: Dry Detention Pond Native Plantings Sumped Outlet Structure Perforated SSD Infiltration Trench _______________________________ ________________________ Owner Signature Date _______________________________ ______________________________ Printed Name Company STATE OF INDIANA ) ) SS: COUNTY OF HAMILTON ) BEFORE ME, the undersigned, a Notary Public in and for said County and State, personally appeared _________________________________ Owner subscribed and sworn before this ____ day of __________________, ________. ______________________________ ______________________________ County of Residence Signature ______________________________ Commission Expiration Date ______________________________ Printed Name Page 9 of 23 William A. Cash 317-490-4036 Appendices Page 10 of 23 William A. Cash 317-490-4036 Sumped Outlet Control Structure R-4342 CASTING GRATING OVER 12'' CORED OPENING 6" SSD CONNECTION AT INV=815.40 2" ORIF ICE INV = 815.40 251•· 4 RIM ELEV = 817,70 '• ~·-· 24" , .. "'• ... Page 12 of 23 William A. Cash 317-490-4036 Storm Sewer Trench ... • •• -1 11-111 ~~~~~~~~~~ .. REGU L AR BACKFILL BED DING MA TE RIAL CONS ISTS OF 3/4 " , CR USHE D STON E HAN D TAM PED rn -~.....:,....c;i.4' n,I TRENCH NOTE S 1. MIN. TRENC H WIDTH TO EQUAL 1.25 TI MES OU TSIDE PIPE DIAM ETER PLU S 12 IN 2 . MIN. 9 IN CLE ARA NC E REQUIRED ON EACH SIDE OF PIPE 3 . ALL BEDDI NG AND INITI AL BACK FILL SHALL BE I STALL ED IN 6 IN TO 12 IN LIFT S 7T ~~~~~~~ i' IIT -=1 ~ - -= =-- -,, ,W Page 13 of 23 William A. Cash 317-490-4036 DRY DETENTION POND BOTTOM TO INCLUDE NATIVE PLANTINGS. NATIVE SEED MIX TO INCLUDE THE FOLLOWING SEED PROPORTIONS: OZ/ACRE SEED TYPE 16 BIG BLUESTEM 32 CANADA WILD RYE 12 VIRGINIA WILD RYE 4 SWITCHGRASS 32 LILLT BLUESTEM 16 INDIAN GRASS Stormwater Management Area SEE SIGN DETAIL ON PAGE 6 SEED & MULC H POND BANKS NA TI VE PLANTINGS PLANTING AREA == so·xso· SEED & MULCH POND BANKS -~~- 0 INFILTRATION TRENCH Page 14 of 23 William A. Cash 317-490-4036 Perforated SSD Infiltration 18'' 6" PERFORATED PLASTIC DUAL -WALL PIPE #8 YASHED STO E BACKFILL GEOTEXTILE FILTER WRAP Page 15 of 23 William A. Cash 317-490-4036 Native Planting Protection Sign GALVANIZED POST HEIGHT = 72" (2 LB/FT POST) STAINLESS HARDWARE CONCRETE FOUNDATION 36" DEPTH 63 MIL ALUMINUM 12X18 SIGN W1 TH ROUNDED CORNERS -SOLID LIGHT BROWN BACKGROUND AND WHITE TEXT TO READ "NATIVE PLAN TINGS -DO NOT MOW OR SPRAY" Page 16 of 23 Storm Sewer Structure Inspection Page 17 of 23 Ins pectio n a nd Ma in te na nce Checkli s t Catch Ba s ins, Ma nhole s, a nd Inle ts Si te Name: Owner Name: Owner Address: Owner Phone Number. Emergen cv Phone Number. Loca tion: Date: Time: ln snector. L.nange m ownersn ,p smce Y OR N last inspectio n? ~tai nle nance Item Mainlenance (I or 2)• Mainlenan<"e is needed: Comments ~h & De b ris Trush or de bris which is localed immcdia1ely in front ot the catch ba,;in o pe ning or is b locting inle.tting capacity o f the ba.,;in by more I.ban 10'1, Trush or dcbris(in I.he basin) lhat cxtted'> 60 percent of lhe sump dcplh a'> measured from I.he bouo m of basin to in\·cn of I.he lowest p ipe into or out of I.he basin. but in oo cu:. le i.s I.ban a minimum of six inche.s clearance from I.he deb ris surface to lhe in\"Crt o f lhe lowest o i..,. Trush or debris in any inle.t or outle.t pipe bloct in~ more than 1/3 o f it,; he i~t Dead animals or \-C-getatioo th:tt could ~nerote odors I.bat could cause compl aints o r dangerou.,; ~a'iCS(C.f. .. me.I.ban:.). Sedimen t Sediment (in the ba,;in) 1.1w exceed,; 60 percent of I.be sump depth as mea,;urcd from the bottom of basin to in\·en of I.he lowest p ipe into or out of I.be basia but in oo c~ le ss lhan a minimum of 6 ioches cl e:irance from thescdime m surface to I.he in\-C rt o f the lowest pipe . Structure Damag,,-t o Frame a ndfo r To p sl.nb ha.'> holes larger lha.n 2 sq~ ind,es Top Slab or cracb wid er I.ban l/4 ioch {lnlent is to make sure no m:uc riaJ is runnin~ into ba.'>in). Frame not sittins n us h o n to p slab. i.e .. separation of more lha.n 3/4 inch o f the frame from the tnn slab. Frame not secure ly attached Frartun-s o r Cracb in Ba.si n Maintenance person j udges that structure is WalL-.IUottom unsound Grout fille.t has sepmued or cr.d :cd v.i der I.ban 1n inch and longer than I foot at the joint o f ru,y inlel/outlet p ipe o r any e\·idenceof so il p.vtid es entering catch ba.'>i n lhroo.gb cracks. SeU.lcm en VMi:saJig nmen t lf fail ure o f ba'>in b.u c rc a1ed a safety. function. or desicn nrnhlcm Veg('tation Ve.getation sro,-.•ing acroi.s and blocking more than 104.otthe 00.'>in o oe.nin l!.. Ve.getation S"°"' i ng in i nleL'outlet p ipe joint'> that is more than six inches tall and Jess lhan six inches ,.n,u, Con taminants and Pollution Any evidence of o il g.!1.'>ol ine. coo.taminanlS or tx.her pollutant.'> (Coordin:ue remo\·al/deanup with local wa1e r aualitv resnnnsea ~ncv). ... a tdl Basin Co,·e r Co\·er is miss ins o r only p:inially in pl.!lce. Any Ollt'-n catch basin ....... uires msinten30C('. Mechanism cannot be o pened by one msintenance person with proper tools. Bo lt'> into frame h.<!Ye 1e-SS than 1/2 inch of I.bread . One mainte nance pe rson cannot rcmo\·e lid afte r 11pply ing nornud l if ting pressure (lntent is to kttp co~-c r from sealins off accc.ss to msintenance). Ladd er Ladder is unsru"edue to miss ing rung..,_ oot securely attached to basin wal l misalignment. ru.'>t. crock.s. or sh" .... ed.~es. M etal Grates Trush and debris lh:u is b lockins more I.ban 204. of .c;rale surface inle.ttin" canx irv. *Ma int ena nce: Ent er 1 if ma intenance 1s need and mdude WO#. Ent er 2 if ma intenance was performed same day Page 18 of 23 Storm Sewer Inspection Checklist Page 19 of 23 Ins pecti on and Mainte na nce Checkli s t Conveyance S to rmwate r Pipe Site Name : Owner Nam e: Owner Address: Owner Phone Number : Emerne ncv Ph one Number: Locatio n: Date: Time: Inspector: Change in ow nership since YOR N las t in specti on? Ma in tenance Item Ma intenance ( I or 2)* Ma inte nance Is aredtd: Commen ts Sedime nt & Debris Acrumulated sedimentexc:ced,; bui ld up 1/4" of the p ipe d iame1e.-up to nm.imum of 6 '" Vegetatio n Vegetation lhat ttduces free mo\'Cmelll of water lhrough the p ifCS Damaged Pipe Protecti,-e coating is danugcd: rust U causing more lhan 50% deterioration to any part of the piJX', A ny dent thal decreases the cross secuon area o t p ipe by more than 20% o r puncture lhat impact,; pcrfonmnce • Mai ntenance : Enter l If maintenance Is need and Include WO#. Enter 2 If maintenance w as performed same day. Page 20 of 23 DETENTION POND MAINTENANCE CHECKLIST Page 21 of 23 STORMWATER MANAGEMENT AREA MAINTENANCE CHECKLIST Stormwater Pond Operation , Maintenance, and Management Inspection Checklist for BMP Owners Project: ___________________ Ow ner Change sin ce las t inspection? Y N Owner Name , Address , Phone ___________________________ _ Numb er ------------------------------------ Lo ca tion :------------------------------------ Site St at us: Date :----------------------------------- T im e: ------------------------------------- Inspector:----------------------------------- Maintenance Item Satisfactory/ Comments Unsatisfactory Embankment and Emergency Spillway (In spect ann uall y and aft er m aj or sto rm s ) 1. V egetation 2. Eros ion on em bankment 3. Anima l burro ws 4. Crac king , bu lging or slidin g of dam A. Location : B. Describ e 5. Drai ns cl ea r and fun cti oning 6. Leaks o r seeps on emban km ent A. Location B. Describe 7. S lope protection f ai lure 8. E merg ency spi llw ay clea r of obst ru ctions 9. Oth er (describe ) Page 22 of 23 STORMWATER MANAGEMENT AREA MAINTENANCE CHECKLIST M a inte na nc e It em S atisfactory/ Comments Unsatisfactory Riser and Pr incipa l spillway (Inspect an nu ally ) Ci rcl e T y pe : Re in force d co ncret e , corrugat ed pi pe , m aso nry 1. Low f low or ifice bl oc ked 2 . T ras h rac k A. d ebris remov al need ed B. co rr os ion no ted 3. Excess ive se d imen t buildu p in rise r 4 . Concrete /Maso nry co nd it io n A. crac ks or d isplace me nt B . spa lli ng 5 . Meta l pipe co nd ition 6. Co ntrol Va lv e o pe rat ion al 7 . Pond drain valve opera t iona l 8. Outfa ll cha nne ls f uncti on ing 9. Oth e r (describe) Pe rm anen t Pool (Inspect m onth ly ) 1. U ndes irable v ege t at ive growt h 2 . Float a ble deb ris remo val needed 3 . Vi sib le po ll ut ion 4 . S ho reline prob le m 5 . Oth e r (describe) Page 23 of 23