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HomeMy WebLinkAboutSW8020637_COMPLIANCE_20030429STORMWATER DIVISION CODING SHEET POST -CONSTRUCTION PERMITS I PERMIT NO. SW DOC TYPE ❑CURRENT PERMIT ❑ APPROVED PLANS ❑ HISTORICAL FILE COMPLIANCE EVALUATION INSPECTION li DOCOATE {JJJ�jO�a`�' YYYYMMDD INFILTRATION BASIN ANALYSIS FILENAME: G:IDATAIWPDATAIWQS1lNBASIN102063 PROJECT NUMBER: SW8 020637-B DATE: 29-Apr-03 PROJECT NAME: Progress Point Master Plan DRAINAGE BASIN: Cape Fear REVIEWER: L. Lewis RECEIVING STREAM: Bradley Creek CLASS: SC # Index No.: 18-87-24-4-(2) SITE AREA: 11.83 acres DRAINAGE AREA: :>::>2021'18` SF IMPERVIOUS AREA CALCULATION Rational C Lot 3 '-44535 1 Lot 2 r� 630591 Lot 1 1 lacr�ase- 1 TOTAL 9392 C Place a "1" here if Rational % IMPERVIOUS, 1= 69'0°fo RV= .05+.009 (!) _ 0 67> ELEVATION OF SEASONAL HIGH WATER TABLE >`€<2 FEET MSL Minimum bottom elevation = 24 fmsl REPORTED INFILTRATION RATE ;;:;:<6 INCHES/HOUR or 0.000139 FPS SURFACE AREAS AND ELEVATIONS Elev. (ft) Area, sq ft Inc. Volume Acc. Volume BOTTOM 24 2636 0 TOP 26.37 6854.35 11246 VOLUME 1 DEPTH 1 DRAWDOWN CALCULATION DESIGN STORM, INCHES :1! DESIGN VOLUME #.125 CUBIC FEET TOTAL VOLUME AVAILABLE :1246 CUBIC FEET STORAGE MET AT ELEVATION :;::: <.;26:46: FEET ELEVATION REPORTED ON PLANS>2637: FEET OK TIME TO DRAWDOWN :.:$',5.: HOURS MUST BE <120 25 YEAR 24 HOUR STORM NIA Intensity, i = .33 inches 1 hour Qr= C i A = CFS Qp through the bottom of the basin= CFS Must be n Qr Intensity, i = 3 inches 1 hour, which is a typical summer thunderstorm Volume for 17 min. event @ 3 in 1 hr = 10673,27 CF < 11246.06475 CF COMMENTS Volume and drawdown are within Design Requirements. Cl=rlKmi"-Hom and Aswc In Inc. Project Information WET DETENTION BASIN - Project Name: Progress Point Master Plan KHA Project #: 011038043 T Designed by: BJM Date: 8/27/2002 Revised by: BJM Date: 11/19/2002 H YR SEAL < e . "s v - 9 a - s Site Information�.� GfNEEP` �� Sub Area Location: A °'••'°°� f fi Drainage Area (DA) = 7.71 Acres (335,858 sf) Z Impervious Area (IA) = 3.91 Acres (170,320 sf) 7 Percent Impervious (1) = 51 % Required Surface Area Permament Pool Depth: 6.0 ft SAIDA = 2.77 % (90% TSS Removal - No Vegetated Filter Required) Min Req'd Surface Area = 9303 sf (at Permanent Pool) Required Storage Volume: Design Storm = 1 inch (Project Does Not Drain to SA waters) Determine Rv Value = 0.05 +.009 (1) = 0.51 inlin Storage Volume Required = 14173 cf (above Permanent Pool) Elevations Bank Elevation = 27.5 It Weir Elevation = 26.1 ft (1' Freeboard) Temporary Pool Elevation = 24.42 ft (Invert of First Drawdown Orifice above Perment Pool Elevation) Permanent Pool Elevation = 23.5 ft Shelf Ending Elevation = 21.5 it Bottom Elevation = 17.5 it Permanent Pool Area; 9794 sf Side Slopes of Pond (above shelf) = 3 : 1 Side Slopes of Shelf = 6 : 1 Side Slopes of Pond (below shelf) = 3 : 1 Is Permenant Pool Surface Area Sufficient (yes./no)? Forebay Volume Permanent Pool Volume = 25451 cf Forebay Volume Required = 5090 cf Top of Forbay Weir Elevation = 23.25 ft Forebay Volume Provided = 5531 cf Side Slopes of Forebay Weir = 3 : 1 1." Rainfall Temporary Storage Volume Provided Temporary Pool Elevation = 24.42 ft Temporary Pool Area = 18483 sf Storage Depth = 0.92 ft Volume Provided = 14236 cf yes ( 9794 > 9303 ) sf (Forebay depth = 5.75 ft) RECEIVED FEB 2 0 2003 DWQ PROJ# 5(ti80Z063-7H0C/ Is Storage Volume Provided Sufficient (yes/no)? yes ( 14236 > 14173 ) cf (Elevation 23.5 to 24.42) u C'•/1 1Gmfey-Horn and Anwate% Inc. WET DETENTION BASIN Project Information c Project Name: Progress Point Master Plan KHA Project #: 011038043 Designed by: BJM Date: 8/27/2002 Revised by: BJM Date: 11/19/2002. Site Information Sub Area Location: A Drainage Area (DA) = 7.71 acres Impervious Area (IA) = 3.91 acres Percent Impervious (1) = 51 % Emergency Spillway Runoff Coefficient (C) = 0.63 Rainfall Intensity (I100) = 10.5 in/hr Drainage Area = 7.71 acres Flow Rate (q,00) = 51.0 cfs qw = 51.0 cfs (Crest Elevation = 26.1) h = 0.5 ft G Cw = 2.7 L = 52 ft Orifice Sizing I N CA IV. ?�Q' o_Ess1°�% QQ SEAL�9< 9 a • a J, M . ►1 Zz�a L 02 can = 0.0820 cfs (Flowrate required for a 2 day drawdown) . Qs Dav3 = 0,0328. cfs (Flowrate required for a 5 day drawdown). . Orifice Size = 1.5 in. (Diameter) O orfte = 0.050 cfs Drawdown Time = 3.275 days less than 5 days (yes/no) ? yes greater than 2 days (yes/no) ? ems_ . Anti -Flotation Device 36" Riser Area: 10.6 st Volume: 42.2 cf Weight: 2636 Ibs Factor of Safety 1.1 r Req'd of Anti -Flotation Device: 2899. Ibs Volume of Concrete Req'd: 19.3 cf Volume Provided: 21.1 cf (Outside Dimension = 44", Inside Dimension = 36") (Water Displaced - Bottom Riser to Top of Bank) (Unit WT of Concrete = 150 pcf) (36" Dia. Pipe filled 2.0' deep with condrete) Orday-Horn and Associates, Inc, WET DETENTION BASIN Project Information Project Name: Progress Point Master Plan KHA Project 4: 011038043 Designed by: BJM Date: 11/19/2002 Wet Detention Basin Elevation/Area[Volurrie Bank Elevation = Temporary Pool Elevation = Permanent Pool Elevation = Forebay Weir Elevation = Bottom Elevation = �o•.•��lrssroy.�ti� 9Qe LgCAI 9< V J ¢W1U '00 Elevation fr Area sf Volume LC Volume Above Perm Pool Volume Below Perm Pool Foreba Area (sf) Volume (cf Sum Volume cf 27.5 25332 12363 88409 -- -- -- -- 27 24118 22928 76046 - -- -- - 26 21737 20579 53119 -- -- -- - 25 19420 18304 32540 -- -- - -- 24.42 18483 7491 14236 -- -- - -- 24 17188 6746 6746. -- -- - -- 23.5 9794 4530 0 25451 -- -- -- 23.25 9059 2173 -- 23095 3045 721 5531 23 8324 7032 -- 20922 2724 2127 4810 22 5739 4935 -- 13890 1529 1220 2683 21 4131 3649 -- 8955 910 742 1464 20 3166 2739 -- 5307 573 444 722 19 2311 1909. -- 2568 314 225 279 18 1507 659 -- 659 136 54 54 17.5 1130 0 - 0 79 0 0 ► ®�,Kimley-Horn and Associates, Inc. INFILTRATION BASIN "B" RECEIVED FEb 2 0 NO B oa # 5(Iifo2C*3-7 Project Information Project Name:, Progress Point Basin "B" KHA Project #: 011038043 Designed by: BJM Date: 02-/11/03 Site Information Sub Area Location: B Drainage Area (DA): 4.64, Acres ( 202,118 sf) Impervious Area (IA): 3.20 Acres ( 139,392 sf) Percent Impervious (1): 69 % Soils Report Soil Type: Leon Sand (Le) and Murville Fine Sand (Mu) Infiltration Rate: 6 in/hr ; 0.5 ft/hr SHWT Elevation: 22 feet Required Volume: Design Storm = 1 inches (Project Does not Drain to SA waters) Determine Rv Value=. 0.05 + .009 (1) = 0.67 in/in Volume Required= 11297 CF Volume Provided Storage Depth = 2.37 feet Surface area @ Bottom = 2636 sq. feet Surface Area @ Storage = 6854.35 sq. feet (Elevation = 26.37) Bottom Elevation = 24 feet (at least 2' above SHWT) Storage Erlevation,= 26.37 feet Volume Provided = 11329 CF Is Volume Sufficient (yes/no)? yes ( 11,329 > 11,297) Drawdown Drawdown Time = total volume / Bottom Surface Area / infiltration = 8.60 Hours less than 5 days (yes/no) ? yes State of North Carolina Department of Environment and Natural Resources Wilmington Regional Office Division of Land Resources Land Quality Section Michael F. Easley, Governor William G. Ross Jr., Secretary October 8, 2002 �, 90 a-/ o V / NOTICE OF RECEIPT OF EROSION & SEDIMENTATION CONTROL PLAN Progress Point One, LLC Mr. James E. Mennifield, Manager 125 Sculey Bark Road Charlotte, NC 28209 Dear Mr. Mennifield: This office has received a soil erosion and sedimentation control plan for the project listed below which was submitted as required by the North Carolina Sedimentation Pollution Control Act (NCGS 113A-57(4)). Please be advised that this Act requires that all persons disturbing an area of one or more acres of land must obtain approval of a soil erosion control plan prior to the commencement of said land -disturbing activity (NCGS 113A-54(d)(4)). The Act further states that this plan must be filed a minimum of 30 days prior to the activity and the approving authority must approve or disapprove the submitted plan within 30 days of receipt. Failure of the approving authority to approve or disapprove the submitted plan within the 30 day period will be deemed approval of the plan if the submitted plan is complete. Commencement or continuation of a land -disturbing activity under the jurisdiction of this Act prior to the approval of an erosion & sediment control plan is.a violation of the Act. A copy of any erosion and sediment control plan which could involve the utilization of ditches for the purpose of dewatering or lowering the water table is forwarded by this office to the Division of Water Quality (DWQ). It is suggested that you contact the Division of Water Quality at (910) 395-3900 if any ditches shown on your plan will lower the water table. We have performed a preliminary review of your submitted plan and have determined that additional information will be necessary before a final review can be completed. Enclosed is a checklist of items that must be submitted before we can complete the review process. Failure to provide the additional information may result in disapproval of your plan. The approval of an erosion and sediment control plan is condition on the applicant's compliance with Federal and State water quality laws, regulations and rules. If you have questions or need additional information, please do not hesitate to contact this office. Your cooperation in this matter is appreciated and we look forward to working with you on this project. Sincerely, Carol N. Miller, CPESC Assistant Regional Engineer CNMlbfr cc: Mike Davidson; Kimley-Horn & Associates, Inc. PROJECT NAME: Mixed Use Site @ Progress Energy Point PROJECT NO.: NH-03089 LOCATION: Eastwood Road - New Hanover County RIVER BASIN: Cape Fear SUBMITTED BY: Kimley-Horn & Associates, Inc DATE RECEIVED BY L.Q.S.: October 7, 2002 127 North Cardinal Drive, Wilmington, N.C. 28405-3845 • Telephone 910-395-3900 a Fax 910-350-2004 An Equal Opportunity Affirmative Action Employer Klm CIm®® andlAssociates.Inc. INFILTRATION BASIN "B" Project Information Project Name: KHA Project #: Designed by: Site Information Sub Area Location: Drainage Area (DA): Impervious Area (IA): Percent Impervious (1): RECEIVED SrP 0 5 ?170?' DWr% PROJ # 56u8 020603� Progress Point Basin "B" 011038043 BJM Date: 06/02/02 (Revised 08/29/02) C 4.48 Acres (195,128 sf) 2.72 Acres (118,484 sf) 61 % Soils Report (provide the following elements, at a minimum) Soil Type: Leon Sand (Le) and Murville Fine Sand (Mu) Infiltration Rate: 6 in/hr = 0.5 ft/hr SHWT Elevation: 22 feet Required Volume: (Simple Method - prefered) Design Storm = 1 inches(Project Does not Drain to SA waters) Determine Rv Value= 0.05 + .009 (1) = 0.60 in/in Volume Required= 9699 CIF Volume Provided Storage Depth = 1.4 feet Surface area @ Bottom = 8921 sq. feet Surface Area @ Storage = 10923 sq. feet Bottom Elevation = 24 feet (at least 2' above SHWT) Storage Elevation = 25.4 feet Volume Provided = 14044 CF Is Volume Sufficient (yes/no)? yes ( 14044 > 9699 ) Drawdown Drawdown Time = total volume / Bottom Surface Area / infiltration 3.15 Hours H�CAR less than 5 days (yes/no) ? yes �Q��'pftglOO�i� 21450 R 4 CI, Kimley-Horn li and Associates, Inc. WET DETENTION BASIN /' Project Information Project Name: Progress Point Master Plan KHA Project #: 011038043 Designed by: BJM Date: 8/27/2002 Site Information Sub Area Location: A Drainage Area (DA) = 7.71 acres Impervious Area (IA) = 3.91 acres Percent Impervious (1) = 51 % Emergency Spillway Runoff Coefficient (C) = 0.63 ••Q.0` ---'�,N s,9 Rainfall Intensity (11co) = 10.5 inlhr S g Drainage Area = 7.71 acres 274 a Flow Rate (q,00) = 51.0 cfs e o� Q qw = 51.0 cfs (Crest Elevation = 26.1) In = 0.5 ft Cw = 2.7 L = 52 ft epF/0' OG Orifice Sizing 02Days = 0.0820 cfs (Flowrate required for a 2 day drawdown) yjW 2 05cays= 0.0328 cfs (Flowrate required for a 5 day drawdown) Orifice Size = 1.5 in. (Diameter) V 0 Orifice = 0.050 cfs Drawdown Time = 3.275 days less than 5 days (yes/no) ? yes greater than 2 days (yes/no) ? yes Anti -Flotation Device 36" Riser Area: 10.6 sf Volume: 42.2 cf Weight: 2636 Ibs Factor of Safety 1.1 f Req'd of Anti -Flotation Device: 2899 Ibs Volume of Concrete Req'd: 19.3 cf Volume Provided: 21.1 cf (Outside Dimension = 44", Inside Dimension = 36") (Water Displaced - Bottom Riser to Top of Bank) (Unit WT of Concrete = 150 pcf) (36" Dia. Pipe filled 2.0' deep with concrete) if r - i ad' C)CI, KpNey-Ham and Assoaates, Inc. Project Information WET DETENTION BASIN Project Name: Progress Point Master Plan _ KHA Project #: 011038043 Designed by: BJM Date: 8/27/2002 Site Information Sub Area Location: A Drainage Area (DA) = 7.71 Acres (335,858 sf) Impervious Area (IA) = 3.91 Acres (170,320 sf) Percent Impervious (1) = 51 % Required Surface Area Permament Pool Depth: 6.0 ft SAlDA = 2.77 % (90% TSS Removal - No Vegetated Filter Required) Min neq'd Surface Area = 9303 st (at Permanent Pool Required Storage Volume: (Simple Method - prefered) Design Storm = 1 inch (Project Does Not Drain to SA waters) Determine Rv Value = 0.05 + .009 (1) = 0.51 in/in Storage Volume Required = 14173 cf (above Permanent Pool) Elevations Bank Elevation = Temporary Pool Elevation 27.5 ft ft Freeboard) = -244 (1' Permanent Pool Elevation = 23.5 ft 0�"off Shelf Ending Elevation = Bottom Elevation = 21.5 17.5 ft ft ee°QO Wet Basin Size Top of Bank = Temporary Pool = Permanent Pool = Shelf Ending = Bottom = Side Slopes of Pond (above shelf) _ Side Slopes of Shelf = Side Slopes of Pond (below shelf) _ Area sf 25332 17, 21975 —`► 2Co CAr 'Z�14 9794 4968 1159 Ii I -- Is Permenant Pool Surface Area Sufficient (yes/no)? yes ( 9794 > 9303) sf Forebay Volume Permanent Pool Volume = 25636 ci Forebay Volume Required = 5127 ci Forebay Volume Provided = 5658 cf ( Forebay depth = 5.75 ft) Side Slopes of Forebay Weir = 3 : 1 1" Rainfall Storage Volume Provided Z 1" Temporary Pool Elevation = 24.41 ft 01-5— 5A Permanent Pool = 9794 sf Storage Depth = 0.91 ft ,L Volume Provided = 14251 cf Is Storage Volume Provided Sufficient (yes/no)? yes ( 14251 n 14173) cf (Elevation 23.5 to 24.41) +h. INFILTRATION BASIN ANALYSIS FILENAME: G:IDATAIWPDATAIWQSIINBASIN102063' PROJECT NUMBER: SW8 020637-B DATE: 15-Nov-02 PROJECT NAME: Progress Point Master Plan DRAINAGE BASIN: Cape Fear REVIEWER: L. Lewis RECEIVING STREAM: Bradley Creek CLASS: SC# Index No.: 18-87-24-4-(2) SITE AREA: 11.83 acres DRAINAGE AREA: >s«1951'28' SF IMPERVIOUS AREA CALCULATION Rational C Lot 3 44535 1 Lot 2 63059 1 Lot 1 10890 1 1 TOTAL 18484: C Place a "1" here if Rational €s % IMPERVIOUS, I= a 0.7Ia' RV= .05+.009 (I) ELEVATION OF SEASONAL HIGH WATER TABLE 22' FEET MSL REPORTER INFILTRATION RATE s<<6! INCHES/HOUR :.......: .:: . ........ . or 0.000139 FPS SURFACE AREAS AND ELEVATIONS Elev. (ft) Area, sq ft Inc. Volume Acc. Volume BOTTOM 24 8921 0 25 10335 9628 9628 TOP 25.4 10923 4251.6 13879.6 VOLUME ! DEPTH 1 DRAWDOWN CALCULATION DESIGN STORM, INCHES .................. . DESIGN VOLUME ><>>9899< CUBIC FEET TOTAL VOLUME AVAILABLE $; CUBIC FEET STORAGE MET AT ELEVATION FEET ELEVATION REPORTED ON PLANS 25 4C1:> FEET OK TIME TO DRAWDOWN 3, it HOURS MUST BE <120 25 YEAR 24 HOUR STORM N/A Intensity, i = .33 inches 1 hour Qr=CiA= 1.01 CFS Qp through the bottom of the basin= 1.24 CFS Must be > Or 10 YEAR 10 MIN HIGH INTENSITY EVENT Intensity, i = 6.3 inches 1 hour Volume for 10 yr. 10 min. event = 11611.85 CF < 13879.6 CF COMMENTS Volume and drawdown are within Design Requirements. SHWT is too high. Either raise bottom or revise to wet pond. DETENTION POND ANALYSIS FILE NAME: G:IDATAIWPDATAIWQSIPOND1020637.WK1 PROJECT #: SW8 020637 REVIEWER: L. Lewis PROJECT NAME: Progress Point Master Plan DATE: 22-Nov-02 Receiving Stream: Bradley Creek Class: SC # Drainage Basin: Cape Fear Index No. 18-87-24-4-(2) Site Area 12.32 acres Drainage Area35:8 00'. square feet Area = 7.71 acres IMPERVIOUS AREAS Rational C Part of Lot 3 56046.00 square feet Lot 5 48065.00 square feet Lot 6 48913.00 square feet Allens Lane 17296.00 square feet Offsite square feet square feet TOTAL 170320;flp; square feet Rational Cc= 0.10 SURFACE AREA CALCULATION % IMPERVIOUS 50.71 % Des. Depth 6 TSS: 90 SA/DA Ratio 2.75% Req. SA 9236 sf Prov. SA J794 sf VOLUME CALCULATION * place a "1" in the box if Rational is used Rational ?* Des. Storm 1..04 inches Rv= 0.51 Bottom 17.5 msl Perm. Pool 23> msl Design Pool 24.42 msl Design SA 18483 sf Req. Volume 14.1 cf Prov. Volume 1.423fi< cf ORIFICE CALCULATION Avg. Head = Flow Q2, cfs Flow Q5, cfs No. of Orifices Diameter, inches Drawdown = ,weir H x W days Perm. Pool Volume= 25451 Req. Forebay Volume= 5090.2 Provided Volume= 5531.00 Percent= 21.7°la SA@24 = 17188 Elevation= 24 COMMENTS Surface Area , Volume and Orifice are within Design Guideline: .3.75 sq. in. 1.50 sq. in. 1.77 sq. in. 0.039 cfs x 17TT in ►l ❑®r, Kimsey -Horn and Associates, ft. Project Information Site information WET DETENTION BASIN Project Name: Progress Point Master Plan KWA Project #: 011038043 Designed by: BJM Date: 8/27/2002 Revised by: BJM Date: 11/19/2002 Sub Area Location: A Drainage Area (DA) = 7.71 Acres (335,858 sf) Impervious Area (IA) = 3.91 Acres (170,320 sf) Percent Impervious (I) = 51 % Required Surface Area Permament Pool Depth: 6.0 SAIDA = 2.77 Min Req'd Surface Area = 9303 RECEIVED NOV 2 0 2002 DWO p of # Sw L U LyCo3 -- ft % (90% TSS Removal - No Vegetated Filter Required) sf (at Permanent Pool) Required Storage Volume: Design Storm = 1 inch (Project Does Not Drain to SA waters) Determine Rv Value = 0.05 + .009 (1) = 0.51 in/in Storage Volume Required = -14173 of (above Permanent Pool) Elevations Bank Elevation = 27.5 it Weir Elevation = 26.1 It (1' Freeboard) Temporary Pool Elevation = 24.42 It (Invert of First Drawdown Orifice above Perment Pool Elevation) Permanent Pool Elevation = 23.5 It Shelf Ending Elevation = 21.5 It Bottom Elevation = 17.5 ft Permanent Pool Area = 9794 st Side Slopes of Pond (above shelf) = 3 : 1 Side Slopes of Shelf = 6 : 1 Side Slopes of Pond (below shelf) = 3 : 1 Is Permenant Pool Surface Area Sufficient (yes/no)? yes ( 9794 > 9303 ) sf Forebay Volume Permanent Pool Volume = 25451 of Forebay Volume Required � 5090 cf Top of Forbay Weir Elevation = 23.25 ft Forebay Volume Provided = 5531 cf (Forebay depth = 5.75 ft) Side Slopes of Forebay Weir = 3 : - 1" Rainfall Temporary Storage Volume Provided Temporary Pool Elevation = 24.42 It Temporary Pool Area = 18483 sf Storage Depth = 0.92 ft Volume Provided = 14236 cf Is Storage Volume Provided Sufficient (yes/no)? yes ( 14236 > 14173 ) cf (Elevation 23.5 to 24.42) JIIIIP�=Fj Kimley-Horn kkkb— and Associales, Inc. WET DETENTION BASIN Project Information Project Name: Progress Point Master Plan KHA Project #: 011038043 Designed by: BJM Date: 8/27/2002 Revised by: BJM Date: 11/19/2002 Site Information Sub Area Location: A Drainage Area (DA) = 7.71 acres Impervious Area (IA) = 3.91 acres Percent Impervious (1) = 51 % Emergency Spillway Runoff Coefficient (C) = Rainfall Intensity (1100) _ Drainage Area = Flow Rate (g100) _ qw = h� CW = L= Orifice Sizing 10.5 inlhr 7.71 acres 51.0 cfs 51.0 cfs (Crest Elevation = 26.1) 0.5 ft 2.7 52 ft 02 Days= 0,0820 cfs (Flowrate required for a 2 day drawdown) 05 Days= 0.0328 cfs (Flowrate required for a 5 day drawdown) Orifice Size = 1.5 in. (Diameter) 0 orifice = 0.050 cfs Drawdown Time = 3.275 days less than 5 days (yes/no) ? yes greater than 2 days (yes/no) ? yes Anti -Flotation Device 36" Riser Area: 10.6 sf Volume: 42.2 cf Weight: 2636 Ibs Factor of Safety 1.1 F Req'd of Anti -Flotation Device: 2899 lbs Volume of Concrete Req'd: 19.3 cf Volume Provided: 21.1 cf (Outside Dimension = 44", Inside Dimension = 36") (Water Displaced - Bottom Riser to Top of Bank) (Unit WT of Concrete = 150 pcf) (36" Dia. Pipe filled 2.0' deep with concrete) KinnleyHorn �..— and Associates, Inc. Project Information Project Name KHA Project # Designed by: WET DETENTION BASIN Progress Point Master Plan 011038043 BJ M Date: 11 /19/2002 Wet Detention Basin Elevation/Areallolume Bank Elevation = Temporary Pool Elevation = Permanent Pool Elevation = Forebay Weir Elevation = Bottom Elevation = Elevation iY Area Sf Volume (cf) Volume Above Perm Pool cf Volume Below Perm Pool cf) Foreba Area Sf Volume cf Sum Volume (cf) 27.5 25332 12363 88409 -- -- -- -- 27 24118 22928 76046 -- - - -- 26 21737 20579 53119 -- - - -- 25 19420 18304 32540 - -- -- - 24.42 18483 7491 14236 -- -- -- - 24 17188 6746 6746 -- -- -- -- 23.5 9794 4530 0 25451 -- -- -- 23.25 9059 2173 -- 23095 3045 721 5531 23 8324 7032 -- 20922 2724 2127 4810 22 5739 4935 -- 13890 1529 1220 2683 21 4131 3649 -- 8955 910 742 1464 20 3166 2739 -- 5307 573 444 722 19 2311 1909 - 2568 314 225 279 18 1507 659 - 659 136 54 54 17.5 1130 0 - 0 79 0 0 4, RECEIVED PROJ # SEP 0 5 2002 PRELIMINARY DwQ NOT FOR CONSTRUCTION GRAPHIC 4 i I t INFILTRATION BASIN ANALYSIS FILENAME: G:IDATAIWPDATAIWQSIINBASIN102063 PROJECT NUMBER: SWE 020637-B DATE: 22-Aug-02 PROJECT NAME: Progress Point Master Plan DRAINAGE BASIN: Cape Fear REVIEWER: L. Lewis RECEIVING STREAM: Bradley Creek CLASS: SC # Index No.: 18-87-24-4-(2) SITE AREA: 11.83 acres DRAINAGE AREA: IMPERVIOUS AREA CALCULATION Lot 3 Lot 2 Lot 1 TOTAL % IMPERVIOUS, 1= $9:S°o'. ELEVATION OF SEASONAL HIGH WATER TABLE REPORTED INFILTRATION RATE SURFACE AREAS AND ELEVATIONS SF Elev. (ft) Area, sq ft Inc. Volume Acc. Volume BOTTOM 24 8921 0 25 10335 9628 9628 TOP 26 11806 11070.5 20698.5 VOLUME 1 DEPTH 1 DRAWDOWN CALCULATION DESIGN STORM, INCHES DESIGN VOLUME ;::::>9438.>' CUBIC FEET TOTAL VOLUME AVAILABLE 20698`96 CUBIC FEET STORAGE MET AT ELEVATION FEET TIME TO DRAWDOWN :<:::::<::4s$:: HOURS MUST BE <120 25 YEAR 24 HOUR STORM NIA intensity, i = .33 inches 1 hour Or-- C i A = 0.92 CFS Qp through the bottom of the basin= 1.24 CFS Must be > Qr 10 YEAR 10 MIN HIGH INTENSITY EVENT Intensity, i = 6.3 inches 1 hour Volume for 10 yr. 10 min. event = 10523.59 CF < 20698.5 CF COMMENTS Volume and drawdown are within Design Requirements. S - �res�iss•-to-�nrad . Project Name: e res5 P���fi Location: Gl� f�1Il- _,__V DIVISION OF WATER QUALITY INFILTRATION SYSTEM INVESTIGATION 1. The minimum bore depth: /T Existing ground elevation: 96.0 0(0.0 Proposed Bottom elevation: Z3 5 Z4- Add 2' +2 +2 +2 +2 Depth: .15 2. The type of soil: Le — f tin 3. The expected infiltration rate:_ h 1'3Y 4. The depth to the Seasonal High Water Table:_ 01- 5 F M 5(, 5. Additional comments: 1 0/� T reCoknM enc/, l.:!7 25 WPa- r�?r5C �-� Signature of Regional Office Personnel: Linda Lewis, DWQ Vincent Lewis, Soil Scientist Permit Application No. 90 ZO&2 Date /(P S:CWQSISTORMWAY&ORMSIINFIIWST.FOR