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Home My WebLink AboutSW6210301_1633 Supplement Wet Pond_20210326SUPPLEMENT-EZ COVER PAGE FORMS LOADED 1PROJECT INFORMATION Project Name Proiect Area (ac) Coastal Wetland Area (ac) 1 Spring Village 2 49.26 3 4 Surface Water Area (ac) 5 Is this r)roiect High — I ow ne—ity? High 6 Does this proiect use an off -site SCM? No COMPLIANCE WITH 02H .1003(4) E=E 7 Width ofvegetated setbacks provided (feet) N/A 8 Will the vegetated setback remain vegetated? 1 9 IlfBUA is proposed in the setback, does it meet NCAC 02H.1003(4)(c-d)? N/A 1 10 1 Is streambank stabilization proposed on this project? ...... . ............. NUMBER AND TYPE OF SCMs: I M 11 Infiltration System 12 Bioretention Cell 13 Wet Pond 6 14 Stormwater Wetland 15 Permeable Pavement 16 Sand Filter 17 Rainwater Harvesting (RWH) 18 Green Roof 19 Level Spreader -Filter Strip (LS-FS) 20 Disconnected Impervious Surface (DIS) 21 Treatment Swale 22 Dry Pond 23 StormFilte 24 Silva Cell I 1 25 113ayfilter IFilterra 1 26 I I FORMS LOADED IDESIGNER CERTIFICATION 27 Name and Title: 28 rganization: Scott Brown, PE - Vice President 4D Site Solutions, Inc 29 Street address: 409 Chicago Drive, Suite 112 30 City, State, Zip: Fayetteville, NC 28306 1 31 JPhone number(s): 910-426-6777 1 32 JEmail: sbrown(a)4dsitesolutions.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. Seal Signature of Designer Date DRAINAGE AREAS 1 Is this a high density project? Yes 2 If so, number of drainage areas/SCMs 6 3 Does this oroiect h.". 1-' '4-ih, areas? No 4 If so. number of 1--, 4-ify drainage areas 0 5 Is all/part of this project subject to previous rule versions? No I FORMS LOADED DRAINAGE AREA INFORMATION Entire Site 1 2 3 4 5 4 Type of SCM Wet pond Wet pond Wet pond Wet pond Wet pond o a rainage area (sq ft) 6 Onsite drainage area (sq ft) 396696 236976 186113 422121 212824 7 Offsite drainage area (sq ft) 65752 78899 14918 193844 28582 8 Total BUA in project (sq ft) 181944 sf 108320 sf 115960 sf 254685 sf 123797 sf 9 New BUA on subdivided lots (subject to permitting) (sq ft) 63525 sf 44225 sf 74856 sf 150272 sf 59261 sf 10 New BUA not on subdivided lots (subject to 1permifting) (sf) 98659 sf 58477 sf 41104 sf 104413 sf 64536 sf 1 11 10fifsite BUA (sq ft) 5618 sf 12 Breakdown of new BUA not on subdivided lots: Parking (sq ft) - Sidewalk (sq ft) Roof (sq ft) - Roadway (sq ft) 71831 sf 46013 sf 24295 sf 78512 sf 43307 sf Future (sq ft) - er, ease spec n e commen ox below (sq ft) 26828 sf 12464 sf 16809 sf 25901 sf 21229 sf 13 New infiltrating permeable pavement on subdivided lots (sq ft) 14 New infiltrating permeable pavement not on subdivided lots (sq ft) 15 Existing BUA that will remain (not subject to Ipermifting) (sq ft) 5618 sf 16 Existing BUA that is already permitted (sq ft) 17 Existing BUA that will be removed (sq ft) 18 Percent BUA 39% 35% 58% 41% 51% 19 Design sto m (inches) 1.0 in 1.0 in 1.0 in 1.0 in 1.0 in 20 Design volume of SCM (cu ft) 22163 cf 14550 cf 14529 cf 32282 cf 14007 cf 21 Calculation method for design volume —J JADDITIONALIN ORRA-50N 1011W JlPlease use this space to provide any additional information about the 22 drainage area(s): Simple Simple Simple Simple Simple I The other BUA listed is for the surface area of the wet ponds which are impervious. DRAINAGE AREAS 1 Is this a high density project? Yes 2 If so, number of drainage areas/SCMs 6 3 Does this oroiect h.". 1-' '4-ih, areas? No 4 If so. number of 1--, 4-ify drainage areas 0 5 Is all/part of this project subject to previous rule versions? No I FORMS LOADED DRAINAGE AREA INFORMATION Entire Site 6 4 Type of SCM Wet pond 5 Total drainage area (sq ft) 98058 6 Onsite drainage area (sq ft) 98058 7 Offsite drainage area (sq ft) 8 Total BUA in project (sq ft) 54278 sf 9 New BUA on subdivided lots (subject to permitting) (sq ft) 30474 sf 10 New BUA not on subdivided lots (subject to permitting) (sf) 23804 sf 11 Offsite BUA (sq ft) 12 Breakdown of new BUA not on subdivided lots: Parking (sq ft) Sidewalk (sq ft) Roof (sq ft) Roadway (sq ft) 19276 sf Future (sq ft) Other, please specify in the comment box be -low (sq ft) 4078 sf 13 INew infiltrating permeable pavement on subdivided lots (sq ft) 14 INew infiltrating permeable pavement not on subdivided lots (sq ft) 15 lExisting BUA that will remain (not subject to permitting) (sq ft) 1 16 lExistina BUA that is already permitted (sq ft) 17 Existing BUA that will be removed (sq ft) 18 Percent BUA 55% 19 Design sto m (inches) 1.0 in 20 Design volume of SCM (cu ft) 6139 cf 21 Calculation method for design volume —J JADDITIONAL IN ORMATION 1111111K JlPlease use this space to provide any additional information about the 22 drainage area(s): I Simple The other BUA listed is for the surface area of the wet ponds which are impervious. WETPOND [--fl Drainage area number 1 21Minimum required treal IGENERAL MDC FROM 02H .1050 3 Is the SCM sized to treat the SW from all surfaces at build -out? Yes Yes Yes Yes Yes 4 Is the SCM located away from contaminated soils? Yes Yes Yes Yes Yes 5 What are the side slopes of the SCM (H:V)? 3:1 3:1 3:1 3:1 3:1 6 Does the SCM have retaining walls, gabion walls or other engineered side slopes? Yes Yes Yes Yes Yes 7 Are the inlets, outlets, and receiving stream protected from erosion 1 (11 0-yea r storm)? Yes Yes Yes Yes Yes 81's there an overflow or bypass for inflow volume in excess of the design volume? Yes Yes Yes Yes Yes 91What is the method for clewatering the SCM for maintenance? Pump (preferred) Pump (preferred) Pump (preferred) Pump (preferred) Pump (preferred) 10 If applicable , will the SCM be cleaned out after construction? Yes Yes Yes Yes Yes 11 Does the maintenance access comply with General MDC (8)? Yes Yes Yes Yes Yes 12 Does the drainage easement comply with General MDC (9)? Yes Yes Yes Yes Yes 13 If the SCM is on a single family lot, does (will?) the plat comply with General MDC (10)? N/A N/A N/A N/A N/A 14 Is there an O&M Agreement that complies with General MDC (111)? I Yes Yes Yes Yes Yes 151 Is there an O&M Plan that complies with General MDC (12)? Yes Yes Yes Yes Yes 161 Does the SCM follow the device specific MDC? Yes Yes Yes Yes Yes 17JWas the SCM designed by an NC licensed professional? Yes Yes Yes Yes Yes WET POND MDC FROM 02H.1053 L 18 Sizing method used SA/DA SA/DA SA/DA SA/DA SA/DA 19 Has a stage/storage table been provided in the calculations? Yes Yes Yes Yes Yes 20 Elevation of the excavated main pool depth (bottom of sediment removal) (fmsl) 297.65 314.20 297.50 296.00 299.00 21 Elevation of the main pool bottom (top of sediment removal) (fmsl) 300.15 315.70 299.00 298.50 301.50 22, Elevation of the bottom of the vegetated shelf (fmsl) 304.65 320.70 303.50 303.00 306.00 23 Elevation of the permanent pool (fmsl) 305.15 320.20 304.00 303.50 306.50 24 Elevation of the top of the vegetated shelf (fmsl) 305.65 320.70 304.50 304.00 307.00 25 Elevation of the temporary pool (fmsl) 306.67 322.40 305.69 305.22 307.84 26 Surface area of the main permanent pool (square feet) 12620 11512 7023 16113 8863 27 Volume of the main permanent pool (cubic feet) 45885 cf 44784 cf 25737 cf 65688 cf 29702 cf 28 Average depth of the main pool (feet) 3.60 ft 3.90 ft 3.70 ft 4.10 ft 3.40 ft 29JAverage depth equation used Equation 2 Equation 2 Equation 2 Equation 2 Equation 2_ 30 If using equation 3, main pool perimeter (feet) 31 If using equation 3, width of submerged veg. shelf (feet) 32 Volume of the forebay (cubic feet) 8494 cf 8441 cf 4947 cf 12517 cf 5842 cf 33 Is this 15-20% of the volume in the main pool? Yes Yes Yes Yes Yes 34 Clean -out depth for forebay (inches) 30 in 18 in 18 in 30 in 30 in 35 Design volume of SCM (cu ft) 22163 cf 14550 cf 14529 cf 32282 cf 14007 cf 361 Is the outlet an orifice or a weir? Orifice Orifice Orifice Orifice Orifice 37 If orifice, orifice diameter (inches) 3 in 2 in 2 in 3 in 2 in 38 If weir, weir height (inches) 39 If weir, weir length (inches) 40 Drawdown time for the temporary pool (days) 2.2 2.5 2.1 2.1 2.3 41 Are the inlet(s) and outlet located in a manner that avoids short- circuiting? Yes Yes Yes Yes Yes 421Are berms or baffles provided to improve the flow path? No No No No No 43 Depth of forebay at entrance (inches) 90 in 72 in 78 in 90 in 90 in 44 Depth of forebay at exit (inches) 78 in 60 in 66 in 78 in 78 in 45 Does water flow out of the forebay in a non -erosive manner? Yes Yes Yes Yes Yes 46 Width of the vegetated shelf (feet) 6 ft 6 ft 6 ft 6 ft 6 ft 47 Slope of vegetated shelf (H:V) 6:1 6:1 6:1 6:1 6:1 48 Does the orifice drawdown from below the top surface of the I pe rma ne nt poo I? Yes Yes Yes Yes Yes 49 Does the pond minimize impacts to the receiving channel from the 1- lyr, 24-hr storm? Yes Yes Yes Yes Yes 50 Are fountains proposed? (If Y, please provide documentation that I MDC(9) is met.) No No No No No 51 1 Is a trash rack or other device provided to protect the outlet system? Yes Yes Yes Yes Yes 52 Are the dam and embankment planted in non -clumping turf grass? Yes Yes Yes Yes Yes 53 Species of turf that will be used on the dam and embankment Centipede Centipede Centipede Centipede Centipede 54 Has a plantinq plan been provided for the vegetated shelf? Yes Yes Yes Yes Yes ,ADDITIONAL INFORMATION 55 Please use this space to provide any additional information about ithe wet pond(s): Wet Pond 1 4:30 PM 3/26/2021 WETPOND [--fl Drainage area number 1 21Minimum required treal IGENERAL MDC FROM 02H .1050 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? Yes 7 Are the inlets, outlets, and receiving stream protected from erosion 1 (11 0-yea r storm)? Yes 81's there an overflow or bypass for inflow volume in excess of the design volume? Yes 91What is the method for clewatering 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)? Yes 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 (111)? 1 Yes 15 Is there an O&M Plan that complies with General MDC (12)? Yes 161 Does the SCM follow the device specific MDC? Yes 17JWas the SCM designed by an NC licensed professional? Yes WET POND MDC FROM 02H.1053 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) 293.00 21 Elevation of the main pool bottom (top of sediment removal) (fmsl) 294.00 221 Elevation of the bottom of the vegetated shelf (fmsl) 298.00 23 Elevation of the permanent pool (fmsl) 298.50 24 Elevation of the top of the vegetated shelf (fmsl) 299.00 25 Elevation of the temporary pool (fmsl) 299.92 26 Surface area of the main permanent pool (square feet) 3429 27 Volume of the main permanent pool (cubic feet) 10453 cf 28 Average depth of the main pool (feet) 3.00 ft 29JAverage depth equation used Equation 2 30 If using equation 3, main pool perimeter (feet) 31 If using equation 3, width of submerged veg. shelf (feet) 32 Volume of the forebay (cubic feet) 1536 cf 33 Is this 15-20% of the volume in the main pool? Yes 34 Clean -out depth for forebay (inches) 12 in 35 Design volume of SCM (cu ft) 6139 cf 361 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) 2.5 41 Are the inlet(s) and outlet located in a manner that avoids short- circuiting? Yes 42jAre berms or baffles provided to improve the flow path? Yes 43 Depth of forebay at entrance (inches) 66 in 44 Depth of forebay at exit (inches) 54 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 I pe rma ne nt poo I? Yes 49 Does the pond minimize impacts to the receiving channel from the 1- lyr, 24-hr storm? Yes 50 Are fountains proposed? (If Y, please provide documentation that I MDC(9) is met.) No 51 1 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 Centipede 54 Has a plantinq plan been provided for the vegetated shelf? Yes 1ADDITIONAL INFORMATION 55 Please use this space to provide any additional information about ithe wet pond(s): Wet Pond 2 4:30 PM 3/26/2021