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Home My WebLink AboutSW6200502_Supplement-EZ Form_20241003 SUPPLEMENT-EZ COVER PAGE FORMS LOADED PROJECT INFORMATION 1 (Project Name Winder Station at Vass 2 Project Area(ac) 27.12 3 Coastal Wetland Area(ac) 0 _ 4 Surface Water Area(ac) 0 5 'Is this project High or Low Density? High 6 'Does this project use an off-site SCM? No COMPLIANCE WITH 02H.1003(4) 7 Width of vegetated setbacks provided(feet) 0 _, 8 Will the vegetated setback remain vegetated? N/A 9 If BUA is proposed in the setback,does it meet NCAC 02H.1003(4)(c-d)? N/A _ 10 Is streambank stabilization proposed on this project? No NUMBER AND TYPE OF SCMs: 11 Infiltration System 12 Bioretention Cell _ - 13 Wet Pond --. 3 14 Stormwater Wetland _ 15 Permeable Pavement 16 Sand Filter 17 Rainwater Harvesting(RWH) I 18 Green Roof 19 'Level Spreader-Filter Strip(LS-FS) 20 Disconnected Impervious Surface(DIS) 21 Treatment Swale 22 Dry Pond 23 I StormFilter —_ 24 'Silva Cell 25 Bayfilter 26 ,Filterra FORMS LOADED DESIGNER CERTIFICATION 27 i Name and Title: John R Wadsworth,PE-Project Engineer 28 Organization: Timmons Group _ 29 Street address: 5410 Trinity Road,Suite 102 30 'City,State,Zip: _ Raleigh,NC 27607 31 I Phone number(s): I _ 919-866-4516 32 Email: ryan.wadsworth@timmons.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. Designer :e•O�te-V E S S/O `�---s-- �''` Si, Designer SEAL 34 \\ 055961 20q r. _ F M � ---�Si w.""' ; �,�• Date �� 1 DRAINAGE AREAS 1 Is this a high density project? Yes 2 If so,number of drainage areas/SCMs 3 , 3 Does this project have low density areas? No 4 If so,number of low density drainage areas 0 Is all/part of this project subject to previous rule 5 versions? I No FORMS LOADED DRAINAGE AREA INFORMATION Entire Site 1 r 2 3 4 I Type of SCM Wet Pond Wet Pond__ Wet Pond _ 5 Total drainage area(sq ft) 813296 325859 240887 246550 6 Onsite drainage area(sq ft) 532016 185581 240887 105548 7 Offsite drainage area(sq ft) 185554 _ 140248 _ 0 __ 45306 8 Total BUA in project(sq ft) 307434 sf 71438 sf 147668 sf 88328 sf New BUA on subdivided lots(subject to permitting) . 9 (sq ft) 45000 sf 85000 sf 51000 sf New BUA not on subdivided lots(subject to 10 permitting)(sf) 126434 sf _ 26438 sf 62668 sf 37328 sf 11 10ffsite BUA(sq ft) 13393 sf 13393 sf _— 4356 sf _12 I Breakdown of new BUA not on subdivided lots: -Parking(sq ft) _ 35000 sf 9000 sf 17000 sf 9000 sf -Sidewalk(sq ft) 11884 sf 2338 sf 6046 sf 3500 sf -Roof(sq ft) _ sf _ -Roadway(sq ft) 79550 sf _ 15100 sf 39622 sf _ 24828 sf -Future(sq ft) -Other,please specify in the comment box below(sq ft) _ New infiltrating permeable pavement on 13 subdivided lots(sq ft) N/A N/A N/A N/A New infiltrating permeable pavement not on 14 subdivided lots(sq ft) N/A N/A N/A N/A Existing BUA that will remain(not subject to 15 permitting)(sq ft) N/A _ N/A N/A N/A 16 Existing BUA that is already permitted(sq ft) 17715 sf 71438 sf 147668 sf 82328 sf 17 Existing BUA that will be removed(sq ft) N/A sf sf sf 18 Percent BUA 26% 26% 61% 38% 19 Design storm(inches) 1.0 in 1.0 in 1.0 in 20 Design volume of SCM(cu ft) 33637 cf 47049 cf 29106 cf _ 21 Calculation method for design volume -- Simple Method Simple Method Simple Method ADDITIONAL INFORMATION Please use this space to provide any additional information about the 22 drainage area(s): Drainge area and calculations remain unchanged.SCM 3 has slightly increased area and BUA from the Major Modification. WET PON D 1 Dralnage area number 1 2 3 _ 2 Minimum required treatment volume(cu ft) ! 9701 cf I 16099 cf I 8084 of GENERAL MDC FROM 0211,,1050 ails the SCM sized to treat the SW from all surfaces at build-out? Yes Yes Yes 4 Is the SCM located away from contaminated soils? Yes Yes Yes 5 What are the side slopes of the SCM(H:V)? 3:1 3:1 3:1 6 Does the SCM have retaining walls,gabion walls or other engineered No No Yes side slopes? 7 Are the inlets,outlets,and receiving stream protected from erosion Yes Yes Yes (10-year storm)? 8 Is there an overflow or bypass for inflow volume in excess of the Yes Yes Yes ,design volume? 9 What is the method for dewatering the SCM for maintenance? Pump(preferred) Pump(preferred) Pump(preferred) 10 If applicable,will the SCM be cleaned out after construction? I Yes Yes Yes 11 Does the maintenance access comply with General MDC(8)? Yes Yes Yes 12 Does the drainage easement comply with General MDC(9)? - Yes Yes Yes 13 If the SCM is on a single family lot,does(will?)the plat comply with N/A N/A N/A General MDC(10)? 14 Is there an O&M Agreement that complies with General MDC(11)? Yes Yes Yes 15 Is there an O&M Plan that complies with General MDC(12)? Yes _ Yes _ _ Yes 16 Does the SCM follow the device specific MDC? Yes Yes Yes 17[Was the SCM designed by an NC licensed professional? Yes Yes Yes WET POND MDC FROP4Q2H.1053: 181Sizing method used SA/DA -_ SA/DA SA/DA 19I Has a stage/storage table been provided in the calculations? Yes Yes Yes 20 Elevation of the excavated main pool depth(bottom of sediment 312.00 291.00 291.00 removal)(fmsl) 21 Elevation of the main pool bottom(top of sediment removal)(fmsl) 313.00 292.00 292.00 _ 22 Elevation of the bottom of the vegetated shelf(fmsl) 317.00 296.00 296.00 23IElevation of the permanent pool(fmsl) 318.00 297.00 297.00 24,Elevation of the top of the vegetated shelf(fmsl) 318.00 297.00 297.00 251 Elevation of the temporary pool(fmsl) _ 319.23 298.23 298.34 26 Surface area of the main permanent pool(square feet) 4720 6999 4007 27 Volume of the main permanent pool(cubic feet) 13244 cf 20533 cf 9936 cf 28±Average depth of the main pool(feet) 3.50 ft 3.50 ft 3.00 ft 29 Average depth equation used ,_ 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) 2456 cf 1794 cf 1794 cf 33 Is this 15-20%of the volume in the main pool? Yes Yes Yes 34 Clean-out depth for forebay(inches) 24 in 24 in 24 in 35 Design volume of SCM(cu ft) 33637 cf 47049 cf_ 29106 cf 36 Is the outlet an orifice or a weir? Orifice Orifice Orifice 371 If orifice,orifice diameter(inches) _1.5 in 1.5 in 1.5 in 381 If weir,weir height(inches) _ _i41 If weir,weir length(inches)Drawdown time for the temporary pool(days) 2.58 2.92 2.58 Are the inlet(s)and outlet located in a manner that avoids short- Yes Yes Yes _circuiting? 421 Are berms or baffles provided to improve the flow path? __ No No No 43 Depth of forebay at entrance(inches) 48 in 48 in 48 in 44 Depth of forebay at exit(inches) 36 in 36 in 36 in 45 Does water flow out of the forebay in a non-erosive manner? J _Yes_ Yes Yes 46 Width of the vegetated shelf(feet) 6 ft Eft 6 ft 47 Slope of vegetated shelf(H:V) 6:1 6:1 6:1 48 Does the orifice drawdown from below the top surface of the No No No permanent pool? 49 Does the pond minimize impacts to the receiving channel from the 1- Yes • Yes Yes yr,24-hr storm? 50 Are fountains proposed?(If Y,please provide documentation that No No No MDC(9)is met.) 51 Is a trash rack or other device provided to protect the outlet system? Yes Yes Yes 52 Are the dam and embankment planted in non-clumping turf grass? Yes Yes Yes 53 Species of turf that will be used on the dam and embankment Bermuda Bermuda Bermuda 54 Has a planting plan been provided for the vegetated shelf? Yes Yes Yes ADDITIONAL INFORMATION 55 Please use this space to provide any additional information about the wet pond(s): Drainge area and calculations remain unchanged.SCM 3 has slightly increased area and BUA from the Major Modification. Wet Pond 3 5:03 PM 8/12/2024