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Home My WebLink AboutSW3230302_Supplement-EZ Form_20240417 SUPPLEMENT-EZ COVER PAGE FORMS LOADED PROJECT INFORMATION 1 Project Name Davis Village _ 2 Project Area(ac) _ 58.78 3 Coastal Wetland Area(ac) _ 0 4 Surface Water Area(ac) 0.91 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) 30 8 Will the vegetated setback remain vegetated? Yes 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 1 14 Stormwater Wetland 15 Permeable Pavement 16 Sand Filter 2 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 Storm Filter 24 Silva Cell 25 Bayfilter 26 Filterra FORMS LOADED DESIGNER CERTIFICATION 27 Name and Title: Edwin Suddreth,Project Manager 28 Organization: W.K.Dickson 29 Street address: 1213 W.Morehead St.Suite 300 30 City,State,Zip: Charlotte,NC 28208 31 Phone number(s): 704-334-5348 32 Email: esuddreth@wkdickson.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 '°'........ CAf 00,ess,o �° fditv QQ '1' `7 S >! Signature of Designer 044570 z,, T suo-.,. 3/28/24 Mar 28 2024 5:42 PM Seal Date 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? Yes _4 If so,number of low density drainage areas _ 1 Is all/part of this project subject to previous rule 5 versions? No I FORMS LOADED I DRAINAGE AREA INFORMATION Entire Site 1 2 3 LD 1 4 Type of SCM Wetpond Sand Filter Sand Filter NA 5 Total drainage area(sq ft) 3408789.36 1220062.44 298217 202574 820055 6 Onsite drainage area(sq ft) 2540908.61 1220062 298217 202574 820055 7 Offsite drainage area(sq ft) 0.00 0 0 0 0 8 Total BUA in project(sq ft) 1027224.00 614342 sf 135651 sf 113957 sf 147559 sf New BUA on subdivided lots(subject to 9 permitting)(sq ft) 661930 sf 427875 sf 42000 sf 64500 sf 127555 sf New BUA not on subdivided lots(subject to ####permitting)(sf) 349579 sf 186467 sf 93651 sf 49457 sf 20004 sf ####Offsite BUA(sq ft) sf ####Breakdown of new BUA not on subdivided lots: sf -Parking(sq ft) 8842 sf 8842 sf sf -Sidewalk(sq ft) 78843 sf 45439 sf 19378 sf 9606 sf 4420 sf -Roof(sq ft) sf sf -Roadway(sq ft) 241066 sf 141028 sf 54985 sf 29469 sf 15584 sf -Future(sq ft) 19288 sf 19288 sf -Other,please specify in the comment box below(sq ft) sf New infiltrating permeable pavement on ####subdivided lots(sq ft) New infiltrating permeable pavement not on ####subdivided lots(sq ft) Existing BUA that will remain(not subject to ####permitting)(sq ft) 1540 sf 1540 sf ####Existing BUA that is already permitted(sq ft) ####Existing BUA that will be removed(sq ft) ##ff#Percent BUA 30% 50% 45% 56% 18% ####Design storm(inches) 1.0 in 1.0 in 1.0 in 1.0 in NA ####Design volume of SCM(cu ft) 68769 sf 49931 cf 9747 cf 9091 cf NA ####Calculation method for design volume Simple Method Simple Method Simple Method Simple Method NA ADDITIONAL INFORMATION Please use this space to provide any additional information about the ####drainage area(s): Future BUA within SCM#2 is for planned amenity WET POND 1 Drainage area number 1 2 Minimum required treatment volume(cu ft 51159 cf GENERAL 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? No 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 No side slopes? 7 Are the inlets,outlets,and receiving stream protected from erosion Yes (10-year storm)? 8 Is there an overflow or bypass for inflow volume in excess of the Yes design volume? _ 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)? Yes 13 If the SCM is on a single family lot,does(will?)the plat comply with N/A General MDC(10)? 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 desi ned b an NC licensed rofessional? 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 549.00 removal)(fmsl) 21 Elevation of the main pool bottom(top of sediment removal)(fmsl) 550.00 22 Elevation of the bottom of the vegetated shelf(fmsl) 555.00 23 Elevation of the permanent pool(fmsl) 555.50 24 Elevation of the top of the vegetated shelf(fmsl) 556.00 25 Elevation of the temporary pool(fmsl) 556.84 _ 26 Surface area of the main permanent pool(square feet) 27785 _ 27 Volume of the main permanent pool(cubic feet) 112672 cf _ 28 Average depth of the main pool(feet) 4.05 ft _ 29 Average 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) 23092 cf 33 Is this 15-20%of the volume in the main pool? Yes _ 34 Clean-out depth for forebay(inches) 6 in 35 Design volume of SCM(cu ft) 49931 cf 36 Is the outlet an orifice or a weir? Orifice 37 If orifice,orifice diameter(inches) 4 in _ 38 If weir,weir height(inches) na _ 39 If weir,weir length(inches) na 40 Drawdown time for the temporary pool(days) 2.2 41 Are the inlet(s)and outlet located in a manner that avoids short- Yes circuiting? 42 Are berms or baffles provided to improve the flow path? Yes 43 Depth of forebay at entrance(inches) 60 in _ 44 Depth of forebay at exit(inches) 72 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 Yes permanent pool? 49 Does the pond minimize impacts to the receiving channel from the 1- Yes yr,24-hr storm? _ 50 Are fountains proposed?(If Y,please provide documentation that No MDC(9)is met.) 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 Native Grasses 54 Has a plantingplan been provided for the vegetated shelf? Yes ADDITIONAL INFORMATION 55 Please use this space to provide any additional information about the wet pond(s): Wet Pond 3 SAND FILTER 1 Drainage area number 2 3 2 Minimum required treatment volume(cu ft) 11416 sf 9391 sf GENERAL MDC FROM 02H.1050 3 Is the SCM sized to treat the SW from all surfaces at build-out? Yes Yes 4 Is the SCM located away from contaminated soils? No No _ 5 What are the side slopes of the SCM(H:V)? 3:1 3:1 6 Does the SCM have retaining walls,gabion walls or other engineered No No side slopes? 7 Are the inlets,outlets,and receiving stream protected from erosion Yes Yes (10-year storm)? 8 Is there an overflow or bypass for inflow volume in excess of the Yes Yes design volume? 9 What is the method for dewatering the SCM for maintenance? Pump(preferred) Pump(preferred) 10 If applicable,will the SCM be cleaned out after construction? Yes Yes 11 Does the maintenance access comply with General MDC(8)? Yes Yes 12 Does the drainage easement comply with General MDC(9)? Yes Yes If the SCM is on a single family lot,does(will?)the plat comply with 13 N/A N/A General MDC(10)? 14 Is there an O&M Agreement that complies with General MDC(11)? Yes Yes 15 Is there an O&M Plan that complies with General MDC(12)? Yes Yes 16 Does the SCM follow the device specific MDC? Yes Yes 17 Was the SCM designed by an NC licensed professional? Yes Yes SAND FILTER MDC FROM 02H.1056 18 SHWT elevation(fmsl) NA 544.38 19 Type of sand filter(open or closed) Open Open 20 If closed,will the filter will be pre-cast or pour-in-place? 21 If closed,top of grate elevation(fmsl) 22 Is this sand filter designed to attenuate peak flows? Yes Yes Sediment Chamber 23 Volume that can be retained in the sediment chamber(cubic feet) 8738 cf 7937 cf 24 Will there be a permanent pool in the sediment chamber? No No 25 Bottom of the sediment chamber(fmsl) 575.00 550.00 26 Area of the sediment chamber(square feet) 6224 sf 3670 sf 27 Physical depth of the sediment chamber(inches) 36 in 36 in 28 Ponding depth in the sediment chamber,above any permanent pool 36 in 36 in (inches) 29 Elevation of top of weir between chambers(fmsl) 577.5 553 (Sand Chamber 30 Volume that can be retained in the sand chamber(cubic feet) 6653 cf 5921 cf 31 Bottom of the sand chamber(fmsl) 575.00 550.00 32 Area of the sand chamber(square feet) 1427 sf 913 sf 33 Physical depth of the sand chamber(inches) 60 in 96 in 34 Ponding depth in the sand chamber,above the sand surface 13 in 18 in (inches) 35 Elevation of the bypass device(fmsl) 577.5 553 36 Type of bypass device Weir _ Weir _ 37 Mechanism for distributing flow over the sand surface Slope Slope _ 38 Sand specification for sand chamber ASTM 33 ASTM 34 39 Depth above underdrain pipe(inches) 27 in 27 in _ 40 Will the media be maintained to drain at least two inches per hour at Yes Yes the sand surface? _ 41 Is at least one clean-out pipe provided at the low point of each Yes Yes underdrain line? 42 Will clean-out pipes be capped? Yes Yes ADDITIONAL INFORMATION 43 Please use this space to provide any additional information about the sand filter(s): Sand Filter 4