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Home My WebLink AboutSW5210303_Supplement-EZ Form_20210519SUPPLEMENT-EZ COVER PAGE FORMS LOADED PROJECT INFORMATION 1 Project Name Burlington Park Apartments - Phase 1 2 Project Area (ac) 8.99 3 Coastal Wetland Area ac 4 Surface Water Area ac - 5 Is this project High or Low Density? High 6 1 Does this project use an off -site SCM? No COMPLIANCE WITH 02H .1005(4 7 !Width of vegetated setbacks provided (feet)- 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 ? No 10 Is streambank stabilization proposed on this project? No NUMBER AND TYPE OF SCMs: 11 Infiltration System Bioretention Cell 0 12 0 13 Wet Pond 1 14 Stormwater Wetland 0 15 Permeable Pavement 0 16 Sand Filter 0 17 Rainwater Harvesting RWH 0 18 Green Roof 0 19 Level Spreader -Filter Strip LS-FS 0 20 Disconnected Impervious Surface (DIS) 0 21 Treatment Swale 0 22 Dry Pond 0 23 StormFilter 0 24 Silva Cell 0 25 Bay titer 0 26 Filterra 0 FORMS LOADED DESIGNER CERTIFICATION 27 Name and Title: Organization: Street address: City. State, Zip: Phone number s.: 1 Email: Matt Lowder, PE 28 Triangle Site Design, PLLC 29 4004 Barrett Dr, Suite 101 30 Raleigh, NC 27609 31 919-553-6570 32 mlowder@trianglesitedesign.com Certification Statement: I certify, under penalty of law that this Supplement-FZ 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. ,•` � t� C�trS�l ,'•`ri r�~a Ci c c°ou' rasa, �I10 Via_,^��ti5�l0,��, c SE-L {yr/ 24434 ■ /� .0 ,S • R Vf amewj6 Signature bf Designer 51 ff /V 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 4 If so, number of low density drainage areas 0 5 Is all/part of this project subject to previous rule versions? No FORMS LOADED DRAINAGE AREA INFORMATION Endre-Site 1 4 Type of SCM Wet Pond Wet Pond 5 Total drainage area (sq ft 391457 288103 6 Onsite drainage area (sq ft 391457 288103 7 Offsite drainage area (sq ft - - 8 Total BUA in project (sq ft 169291 sf 169291 sf 9 New BUA on subdivided lots (subject to permitting) (sq ft - 10permitting) New BUA not on subdivided lots (subject to sf - 11 Offsite BUA (sq ft) - 12 Breakdown of new BUA not on subdivided lots: - Parkin (sq ft 97178 sf 97178 sf - Sidewalk (sq ft 16423 sf 16423 sf - Roofs ft 55690 sf 55690 sf - Roadway s ft - Future (sq ft - - - - Other, please specify in the comment box below (sq ft 13 New infiltrating permeable pavement on subdivided lots (sq ft 14 New infiltrating permeable pavement not on subdivided lots (sq ft 15permitting) Existing BUA that will remain (not subject to s ft - 16 Existing BUA that is already permitted s ft 17 x stino BUA that will be removed (sq ft 10050 sf 6098 sf 18 Percent BUA 43% 59% 19 Design storm inches 1.0 in 20 Design volume of SCM cu ft 13910 cf 21 Calculation method for design volume I Simple Method INFORMATION Please use this space to provide any additional information about the 22 The proposed SCM has been oversized in anticipation for future phases. The maximum overall drainage area will be 8.78 ac with a maximum BUA of 5.91 ac. The combined Phase 1 and future Phase 2 drainage area yielded a design volume of 20,905 cf (a difference of 6995 cf). WET POND 1 Draina earea number 1 2 Minimum required treatment volume cu ft 13910 cf GENERAL MOC FROM MR11 4050 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- ear 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 referred 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 (11)? Yes 15 Is there an O&M Plan that complies lies with General MDC (12)? Yes 16 Does the SCM follow the devicespecific MDC? Yes 17 Was the SCM designed b an NC licensedprofessional? Yes WET POND N= FROM 02M.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) _ Elevation of the main pool bottom (top of sediment removal) (fmsl) 374.00 21 375.00 22 Elevation of the bottom of the vegetated shelf fmsl 379.50 23 Elevation of the permanent pool fmsl 380.00 24 Elevation of the top of the vegetated shelf fmsl 380.50 25 Elevation of the temporary pool fmsl 381.40 26 Surface area of the main permanent pool (square feet 10140 27 Volume of the main permanent pool (cubic feet) 35815 cf 28 Average depth of the main pool (feet) 4.03 ft 29 Average depth euation used Equation 3 30 If using equation 3, main pool perimeter feet 458.0 ft 31 If using equation 3, width of submerged veg. shelf feet 3.0 ft 32 Volume of the foreba (cubic feet) 6484 cf 33 Is this 15-20% of the volume in the mainpool? Yes 34 Clean -out depth for foreba inches 36 in 35 Desi n volume of SCM (cu ft) 13910 cf 36 Is the outlet an orifice or a weir? Orifice 37 If orifice, orifice diameter inches 2.25 in 38 If weir, weir height inches 39 If weir, weir length (inches) 40 Drawdown time for the temporapool (days) 2.18 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 ath? Yes 43 Depth of forebay at entrance inches 48 in 44 Depth of forebay at exit (inches) 42 in 45 Does water flow out of the forebay in a non -erosive manner? Yes 46 Width of the vegetated shelf (feet) 6 It 47 Slope of vegetated shelf H: 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 r 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 Hybrid Bermuda 54 Hasa planting plan been provided for the vegetated shelf? Yes ADDITIONAL INFORMATION Please use this space to provide any additional information about 55 the wet pond(s): Wet Pond 2 11:18 AM 5/11/2021