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Home My WebLink AboutSW5210603_Supplement-EZ Form_20211111SUPPLEMENT-LEZ COVER PAGE FORMS LOADED PROJECT INFORMATION Duck Thru at Spring Hope Project Name ProjectArea ac 4.87 L32 Coastal Wetland Area acSurface Water Area ac 5 Is this project High or Low Density? High 6 Does this project use an off -site SCM? Yes COMPLIANCE WITH 02H .1003(4) 71 Width of vegetated setbacks pr 8 IWill the vegetated setback 9 Ilf BUA is proposed in the s 10 lis streambank stabilization on this NCAC N/A No _T NUMBER AND TYPE OF SCMs: - _ Infiltration System 12 Bioretention Cell r11 13 Wet Pond 1 14 Stormwater Wetland 15 Permeable Pavement Sand Filter Rainwater Harvesting RWH r2O Green Roof Level Spreader -Filter StripLS-FS DisconnectedImpervious Surface DIS 21 Treatment Swale 22 Dry Pond 23 StormFilter 24 Silva Cell 25 Bayfilter Filterra _ 26 FORMSLOADED IDESIGNER CERTIFICATION-�--_- =- J. Michael Stocks, PE President 27 Name and Title: Stocks Engineering, PA 28 Organization: 801 East Washington Street 29 Street address: City, State, Zip: Phone numbers : Email: Nashville, NC 27856 252.459.8196 mstocks@stocksengineering.com 30 31 32 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. �♦. `,IN CARD ♦ 4 ...••••• •�f 0I0, o •.,.yy a SEAL ? 19843 *7 of Designer to/ 12 L Date DRAINAGE AREAS 1 Is this a high density project? Yes 2 If so, number of drainage areas/SCMs 2 3 Does this oroiect have low densit areas? No 4 If so number of low densit drainage areas 0 5 Is all/part of this project subject to previous rule versions? No FORMS LOADED DRAINAGE AREA INFORMATION Entire Site 1 2 4 Type of SCM Wet Pond Wet Pond 5 Total drainage area (sq ft 218415 189255 11051 6 Onsite drainage area (sq ft 212651 183491 11051 7 Offsite drainage area (sq ft 5764 5764 0 8 Total BUA in project (sq ft) 158592 sf 156242 sf 2350 sf 9permitting) New BUA on subdivided lots (subject to s ft 158592 sf 156242 sf 2350 sf 10 New BUA not on subdivided lots (subject to permitting) (sf) 11 Offsite BUA (sq ft sf sf sf 12 Breakdown of new BUA not on subdivided lots: - Parking (sq ft 152196 sf 149846 sf 2350 sf - Sidewalk (sq ft 2196 sf 2196 sf sf - Roof (sq ft 4200 sf 4200 sf 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 lExistina BUA that is already permitted (sq ft 17 Existing BUA that will be removed (sq ft 18 Percent BUA 73% 83% 21% 19 Design storm inches 1.0 in 1.0 in 20 Design volume of SCM cu ft 12549 cf 209 cf 21 Calculation method for design volume Simple Simple ADDITIONAL INFORMATION Please use this space to provide any additional information about the 22 drainage area(s): OFF -SITE SCM THE DRAINAGE AREA 1 Drainage area number for this project 2 2 Master permit number SW5200701 3 Drainage area number from the master permit 4 Lot or outparcel number 1 5 j BUA allocated by Master Permit 2350 sf INFORMATION ABOUT THE OFF -SITE SCM 6 Type of off -site SCM Wet Pond 7 Available treatment capacity in the off -site SCM (cu ft) 6474 cf 8 Have deed restrictions limiting the BUA on the site been recorded? No 9 Has an Engineer's Certification for the off -site SCM been submitted to DEQ? Yes 10 Are there any Notices of Violation for the off -site system? No 11 Has the off -site SCM been maintained in accordance with its O&M Plan? Yes 12 Will the collection system be maintained in its design state and kept clean? Yes ADDITIONAL INFORMATION 13 1 Please use this space to provide any additional information about the off -site SCM(s): The total treatment capacity of the offsite SCM for SW5200701 is 19,076 cf. Currently, the wet pond for SW5200701 has been permitted to treat 12,602 cf. Therefore, the available treatment capacity is 6,474 cf. WET POND Drainaae area number 21 Minimum required treatment volume cu ft 12549 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? 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-year 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 (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 (11)? 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 17 Was the SCM designed by an NC licensedprofessional? 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 251.00 21 Elevation of the main pool bottom (top of sediment removal) (fmsl) 252.00 221 Elevation of the bottom of the vegetated shelf (fmsl) 259.00 23 Elevation of the permanent pool (fmsl) 260.00 24 Elevation of the top of the vegetated shelf fmsl 260.00 25 Elevation of the temporary pool (fmsl) 261.43 26 Surface area of the main permanent pool (square feet 5762 27 Volume of the main permanent pool (cubic feet) 19092 cf 28 Average depth of the main pool feet 3.00 It 29 Average depth equation used Equation 2 30 If usinga uation 3, main pool perimeter feet 31 If using equation 3, width of submerged veg. shelf (feet) 32 Volume of the forebay cubic feet 3157 cf 33 Is this 15-20% of the volume in the main pool? Yes 34 Clean -out depth for forebay inches 48 in 35 Design volume of SCM (cu ft) 31063 cf 361 Is the outlet an orifice or a weir? Orifice 37 If orifice, orifice diameter (inches) 2 in 38 If weir, weir height inches 39 If weir, weir length (inches) 40 Drawdown time for the temporary pool (days) 2.4 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 path? No 43 Depth of forebay at entrance (inches) 255 in 44 Depth of forebay at exit (inches) 259 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 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 Centipede 54 Hasa plantinq plan been provided for the vegetated shelf? Yes ADDITIONAL INFORMATION IF 55 Please use this space to provide any additional information about the wet pond(s): Should the 5,764 sf of offsite drainage area become built upon The Duck Thru Pond has an additional 18,514 cf of storage available to treat the increase in impervious area. Wet Pond 4 10:55 AM 11/11/2021