SW3200401_17031-PH2 SSW-SuppEZ-20170329-DEMLR-SW_20200612

QuantityInfiltration System0Bioretention Cell0Wet Pond1Stormwater Wetland0Permeable Pavement0Sand Filter1Rainwater Harvesting0Green Roof0Level Spreader-Filter Strip0Disconnected Impervious Surface 0Treatment Swale0Dry Pond0Applicant:Name and Title:Organization:Street address:City, State, Zip:Phone number(s):Email:DesignerCertification Statement:Signature of DesignerDateEmail:3037 Sherman DriveLancaster, SC 29720844-566-4300Company:Contact:Mailing Address:City, State, Zip:Project Name:AddressCity / TownLGI HomesJeff Webb - VP of Land DevelopmentVillage at Granite Quarry - Phase 2Salisbury, Rowan Co3040 Faith RoadBMP #8SUPPLEMENT-EZ FORM COVER PAGESealviolations as well as a report being made to my professional board.- that the information provided in the form is, to the best of my knowledge-that the engineering plans, specifications, operation and maintenancethe information provided here.I am aware that there are significant penalties for submitting falseinformation including the possibility of fines and imprisonment for knowing and belief, true, accurate, and complete; andagreements and other supporting information are consistent withI certify, under penalty of law: that this Supplement-EZ form and all supportinginformation were prepared under my direction or supervision; Designer information for this project:Location(s)Please indicate the types, quantities and locations of SCMs that will be used on this project:[e-mail] number(s):Hy V. NguyenDPR Associates, Inc420 Hawthorne LaneCharlotte, NC [e-mail] #7Cover Page112:12 PM 3/16/2020June 12, 2020
WET POND1 Drainage area number7 Total coastal wetlands area (sq ft)0 sf - Parking / driveway (sq ft)0 sfTotal surface water area (sq ft)0 sf - Sidewalk (sq ft)42,450 sfTotal drainage area (sq ft)1,132,560 - Roof (sq ft)303,890 sfBUA associated with existing development (sq ft) 0 sf - Roadway (sq ft)106,730 sfProposed new BUA (sq ft)469,140 - Other, please specify in the comment box below (sq ft) 16,070 sf Percent BUA of drainage area41.42%Total BUA (sq ft)469,140 sf Design rainfall depth (in)1.0 inMinimum volume required (cu ft) 41,244 cfDesign volume of SCM (cu ft)164,875 cf#1 Is the SCM sized to treat the SW from all surfaces at build-out? Yes#7 If applicable, with the SCM be cleaned out after construction?Yes#2 Is the SCM located on or near contaminated soils? No#8 Does the mainetenance access comply with General MDC (8)?Yes#3 What are the side slopes of the SCM (H:V)? 3:1#9 Does the drainage easement comply with General MDC (9)?Yes#3 Does the SCM have retaining walls, gabion walls or other engineered side slopes? No#10 If the SCM is on a single family lot, does the plat comply with General MDC (10)?Yes#4 Are the inlets, outlets, and receiving stream protected from erosion (10-year storm)? Yes#11 Is there an O&M Agreement that complies with General MDC (11)?Yes#5 Is there a a bypass for flows in excess of the design flow? No#12 Is there an O&M Plan that complies with General MDC (12)?Yes#6 What is the method for dewatering the SCM for maintenance?Pump (preferred)#13 Was the SCM designed by an NC licensed professional?Yes#1 Method usedSA/DA#6 Width of the vegetated shelf (feet)6 ft#1 Surface area of the main permanent pool (square feet) 17,000 sf#6 Location of vegetated shelf@ Normal Pool#1 Volume of the main permanent pool (cubic feet) 91,800 sf#6 Elevation of top of shelf (fmsl)722.0 ft#2 Average depth of the main pool (feet) 5 ft #6 Elevation of bottom of shelf (fmsl)721.0 ft#2 Was the vegetated shelf included in the calculation of average depth? Yes #6 Slope of vegetated shelf (H:V)6:1#2 Elevation of the bottom of the permanent pool (fmsl) 714.0 ft #7 Diameter of drawdown orifice (inches)3.0 in#2 Elevation of the top of the permanent pool (fmsl) 721.5 ft #7 Drawdown time for the temporary pool (hours)96 hrs#2 Elevation of the top of the temporary pool (fmsl) 729.5 ft #7 Does the orifice drawdown from below the top surface of the permanent pool?No#3 Depth provided for sediment storage (inches) 6 in#8 Does the pond minimize impacts to the receiving channel from the 1-yr, 24-hr storm? Yes#4 Are the inlet(s) and outlet located in a manner that avoids short-circuiting?Yes #9 Are fountains proposed?Yes#9 If yes, is documentation provided per Wet Pond MDC (9)? Yes#10 Is a trash rack or other device provided to protect the outlet system? Yes#5 Volume of the forebay (cubic feet) 16,750 cf#11 Are the dam and embankment planted in non-clumping turf grass? Yes#5 Is this 15-20% of the volume in the main pool? Yes#11 Species of turf that will be used on the dam and embankment Matting#5 Depth of forebay at entrance (inches) 96 in#11 Describe the planting plan for the vegetated shelf:#5 Depth of forebay at exit (inches) 96 in#5 Does water flow out of the forebay in a non-erosive manner? Yes#5 Clean-out depth for forebay (inches) 6 in#5 Will the forebay be cleaned out when the depth is reduced to less than the above? NoTHE DRAINAGE AREABreak down of BUA in the drainage area (both new and existing):COMPLIANCE WITH THE APPLICABLE STORMWATER PROGRAMStormwater program(s) that apply (please specify):Stormwater Detention Control 2 year ans 10 year storm events, Water Quality design to treat the first inch of runoff.WET POND MDC FROM 02H .1053#4 Describe any measures, such as berms or baffles, that will be taken to improve the flow path:2 forebay for pond with earth berms between main pool and forebay with riprap on top 4' vert.See Planting Plan on sheet L-12 (Cardinal Flower, Joe Pye Weed, Marsh Mallow, Duck Potato, Sweet Flag and Souther Blue Flag)ADDITIONAL INFORMATIONPlease use this space to provide any additional information about this wet pond that you think is relevant to the review:GENERAL MDC FROM 02H .1050Village at Granite Quarry - Phase 2Wet Pond111:20 AM 6/12/2020
SAND FILTER1Drainage area number8Total coastal wetlands area (sq ft) sf- Parking / driveway (sq ft) sfTotal surface water area (sq ft) sf- Sidewalk (sq ft)7700 sfTotal drainage area (sq ft)283,140 sf- Roof (sq ft)69,115 sfBUA associated with existing development (sq ft) sf- Roadway (sq ft)24,644 sfProposed new BUA (sq ft)113,256 sf (Design)- Other, please specify in the comment box below (sq ft) sfPercent BUA of drainage area40.0% (Design)Total BUA (sq ft)100,959 sf (Actual)Design rainfall depth (in)1.0 inMinimum volume required (cu ft)7,255 cfDesign volume of SCM (cu ft)57,450 cf#1 Is the SCM sized to treat the SW from all surfaces at build-out?Yes#7 If applicable, with the SCM be cleaned out after construction?Yes#2 Is the SCM located on or near contaminated soils?No#8 Does the mainetenance access comply with General MDC (8)?Yes#3 What are the side slopes of the SCM (H:V)?3:1#9 Does the drainage easement comply with General MDC (9)?Yes#3 Does the SCM have retaining walls, gabion walls or other engineered side slopes? No#10 If the SCM is on a single family lot, does the plat comply with General MDC (10)?Yes#4 Are the inlets, outlets, and receiving stream protected from erosion (10-year storm)?Yes#11 Is there an O&M Agreement that complies with General MDC (11)?Yes#5 Is there a a bypass for flows in excess of the design flow?No#12 Is there an O&M Plan that complies with General MDC (12)?Yes#6 What is the method for dewatering the SCM for maintenance?Drawdown Orifice#13 Was the SCM designed by an NC licensed professional?Yes#1 SHWT elevation (fmsl)718.81 ft #3 Volume of stormwater from drainage area during design storm (cubic feet)181,929 cf#1 Type of sand filter (open or closed)Open #3 Total volume that can be stored above the sediment and sand chambers (cubic feet)45850 cf#1 If closed, describe if the filter will be pre-cast or pour-in-place:#3 Is this sand filter designed to attenuate peak flows?Yes#3 Elevation of the bypass device (fmsl)N/A#1 If closed, top of grate elevation (fmsl)N/A#2 Volume that can be retained in the sediment chamber (cubic feet)1,935 cf#2 Will there be a permanent pool in the sediment chamber?No#2 Bottom of the sediment chamber (fmsl)732 ft#4 Ponding depth from the top of the sand to the bypass device (ft)N/A#2 Area of the sediment chamber (square feet)5,900 sf#2 Physical depth of the sediment chamber (inches)60 in#2 Ponding depth in the sediment chamber, above any permanent pool (inches)41.4 in#2 Elevation of top of weir between chambers (fmsl)736.00'#2 Volume that can be retained in the sand chamber (cubic feet)43,600 cf#2 Bottom of the sand chamber (fmsl)731 ft #7 Depth above underdrain pipe (inches)33 in#2 Area of the sand chamber (square feet)1000 sf#8 Will the media be maintained to drain at least two inches per hour at the sand surface?No#2 Physical depth of the sand chamber (inches)24 in #9 Is at least one clean-out pipe provided at the low point of each underdrain line?Yes#2 Ponding depth in the sand chamber, above any permanent pool (inches)53.4 in#9 Will clean-out pipes be capped? YesTHE DRAINAGE AREAGENERAL MDC FROM 02H .1050Break down of BUA in the drainage area (both new and existing):COMPLIANCE WITH THE APPLICABLE STORMWATER PROGRAMStormwater program(s) that apply (please specify):Stormwater Detention Control 2 year ans 10 year storm events, Water Quality design to treat the first inch of runoff.Please use this space to provide any additional information about this sand filter that you think is relevant to the review:SAND FILTER MDC FROM 02H .1056ADDITIONAL INFORMATIONN/AN/A#3 Describe the bypass device:#5 Describe the mechanism for distributing flow over the sand surface:#6 Sand specification for sand chamber ASTM C-33 MEDIUM AGGREGATE CONC. SANDN/AVillage at Granite Quarry - Phase 2Sand Filter13:16 PM 3/12/2020