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Home My WebLink AboutSW1220801_Stormwater Report_20230214 (3)SUPPLEMENT-EZ COVER PAGE FORMS LOADED PROJECT INFORMATION 1 Project Name 2 !Project Area (ac) 3 'Coastal Wetland Area (ac) 4 Surface Water Area (ac) 5 is this ro'ect High or Low Density? -. _ 6 Does this project use an off -site SCM? Sparks Drive Commercial Building 1.37 0 0 High No 7 Width of vegetated setbacks provided (feet) >30 ft 8 Will the veaetated setback remain vegetated? N/A 9 If BUA is proposed in the setback, does it meet NCAC 02H. 1 003(4)(c-d)? N/A 10 Is streambank stabilization proposed on this project? No NUMBER AND TYPE OF SCMs: 11 Infiltration System 12 r1 Bioretention Cell 13 Wet Pond 4 Stormwater Wetland 25 , Bayfilter _ 26 Filterra FORMS LOADED DESIGNER CERTIFICATION 27 Name and Title: Kevin Pulis, PE 28 Or anization: Tarr Group, LLC 29 I!Street address: 8650 E. State Rd 32 30 City, State, Zip: Zionsville, IN 46077 31 Phone number(s): 843-633-3579 32 Email: kevin@tarr-group.com Certification Statement: I certify, under penalty of law that this Supplement-EZ form and all supporting information were prepared under my direction or supervision; that the information provided in the form is, to the best of my knowledge and belief, true, accurate, and complete; and that the engineering plans, specifications, operation and maintenance agreements and other supporting information are consistent with the information provided here. H tCIAIRp1''''',, '' %. SEAL 042797 FNGINE�� 019nature or DmIgner al /,Qg 1A 02 3 Date DRAINAGE AREAS 1 Is this a high density project? Yes 2 If so, number of drainage areas/SCMs 1 3 Does this project have low density areas? No If so, number of low densitydrainage areas 0 t54 Is all/part of this project subject to previous rule versions? No FORMS LOADED DRAINAGE AREA INFORMATION Entire Site 1 4 Type of SCM Wet Pond 5 Total drainage area (sq ft) 59677 48600 6 Onsite drainage area (sq ft) 59677 48600 7 Offsite drainage area (sq ft) zero zero 8 Total BUA in project (sq ft 36409 sf 32532 sf 9 New BUA on subdivided lots (subject to permitting) (sq ft zero zero 10 New BUA not on subdivided lots (subject to permitting) (so zero zero 11 Offsite BUA (sq ft) zero zero 12 Breakdown of new BUA not on subdivided lots: - Parking (sq ft) 27108 sf 23231 sf - Sidewalk (sq ft) 1435 sf 1435 sf - Roof (sq ft) - Roadway (sq ft) - Future (sq ft) - Other, please specify in the comment box below (sq ft New infiltrating permeable pavement on subdivided 1 lots (sq ft New infiltrating permeable pavement not on subdivided lots (sq ft) 7378 sf 7378 sf zero zero zero zero 488 sf 488 sf 13 zero zero 14 zero zero 15 Existing BUA that will remain (not subject to permitting) (sq ft) zero zero 16 Existing BUA that is already permitted (sq ft) zero zero 17 Existing BUA that will be removed (sq ft) zero zero 18 Percent BUA 61 % 67% 19 Design storm inches 1.0 in 20 Design volume of SCM (cu ft) 2645 cf 21 1 Calculation method for design volume ADDITIONAL INFORMATION Please use this space to provide any additional information about the 22 drainage area(s): 488 sf represents dumpster enclosure. The SCM is being oversized to account for the 3,877 sf of drive aisle that bypasses. Simple WET POND 1 Drainage area number 1 21 Minimum required treatment volume cu ft 2645 cf UtNt iL Iylul murvi 62H .luau 3 Is the SCM sized to treat the SW from all surfaces at build -out? Yes 4 Is the SCM located away from contaminated soils? Yes 5 What are the side slopes of the SCM (H:V)? 3:1 6 Does the SCM have retaining walls, gabion walls or other engineered side slopes? No 7 Are the inlets, outlets, and receiving stream protected from erosion (10-year storm)? Yes 8 Is there an overflow or bypass for inflow volume in excess of the design volume? Yes 9 What is the method for dewatering the SCM for maintenance? Pump (preferred) 10 If applicable, will the SCM be cleaned out after construction? Yes 11 Does the maintenance access comply with General MDC (8)? Yes 12 Does the drainage easement comply with General MDC (9)? >30 ft 13 If the SCM is on a single family lot, does (will?) the plat comply with General MDC (10)? N/A 14 Is there an O&M Agreement that complies with General MDC (11)? Yes 15 Is there an O&M Plan that complies with General MDC (12)? Yes 16 Does the SCM follow the device specific MDC? Yes 17 Was the SCM designed by an NC licensedprofessional? Yes IAA/FT PnK]n Mnr FRnm n7H _1 OSR 18 Sizing method used SA/DA 19 Has a stage/storage table been provided in the calculations? Yes 20 Elevation of the excavated main pool depth (bottom of sediment removal) (fmsl) 989.00 21 Elevation of the main pool bottom (top of sediment removal) (fmsl) 989.50 22 Elevation of the bottom of the vegetated shelf (fmsl) 993.00 23 Elevation of the permanent pool (fmsl) 994.00 24 Elevation of the top of the vegetated shelf (fmsl) 994.00 25 Elevation of the temporary pool (fmsl) 995.25 26 Surface area of the main permanent pool (square feet) 1642 sf 27 Volume of the main permanent pool (cubic feet) 2562 cf 28 Average depth of the main pool (feet) 3.05 ft 29 Average depth equation used Equation 3 30 If using equation 3, main pool perimeter (feet) 110.0 ft 31 If using equation 3, width of submerged veg. shelf (feet) 6.0 ft 32 Volume of the forebay (cubic feet) 496 cf 33 Is this 15-20% of the volume in the main pool? Yes 34 Clean -out depth for forebay (inches) 30 in 35 Design volume of SCM (cu ft) 3188 cf 36 Is the outlet an orifice or a weir? Orifice 37 If orifice, orifice diameter (inches) 1 in 38 If weir, weir height (inches) 39 If weir, weir length (inches) 40 Drawdown time for the temporary pool (days) 2.25 41 Are the inlet(s) and outlet located in a manner that avoids short- circuiting? Yes 42 Are berms or baffles provided to improve the flow path? Yes 43 Depth of forebay at entrance (inches) 48 in 44 Depth of forebay at exit (inches) 36 in 45 Does water flow out of the forebay in a non -erosive manner? Yes 46 Width of the vegetated shelf (feet) 6 ft 47 Slope of vegetated shelf (H:V) 6:1 48 Does the orifice drawdown from below the top surface of the permanentpool? Yes 49 Does the pond minimize impacts to the receiving channel from the 1- yr, 24-hr storm? Yes 50 Are fountains proposed? (If Y, please provide documentation that MDC(9) is met.) No 51 Is a trash rack or other device provided to protect the outlet system? Yes 52 Are the dam and embankment planted in non -clumping turf grass? Yes 53 Species of turf that will be used on the dam and embankment Fescue 54 Has a P antinq plan been provided for the vegetated shelf? Yes DITIONAL INFORMATION 55 Please use this space to provide any additional information about the wet pond(s): Exact SHWT elevation not established, geotech report says it is deep. Clay liner used to establish permanent pool. The SCM has been oversized to account for BUA that bypasses.