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HomeMy WebLinkAboutDrainage Report0-g ". %"*do Surveying Site Design Civil Engineering Urban Planning Water Quality Designs 241 5 Directors Row 5te.E Indianapolis, In 46241 31 7-244-1 968 FAX-244--1 969 DRAINAGE REPORT FOR WESTON POINTE RETAIL CENTER OUTLOT #3 1 1 145 NORTH MICHIGAN ROAD CARMEL, INDIANA June 22, 2007 Dmitlage Repo~t Weston Pointe Retd Center - Lot nF 3 Table of Contents S ullunay. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Appendix A Maps Appendix B Existing Conditions Appendix C Proposed Conditions Appendix D Inlet Capacity \Vorksheets Appendix E Water Qudty Weston Pointe Retail Center - Lot # 3 U.S. 42 1 & Weston Pointe Di-ive Introduction: 11e existing 1.22 +/- xre site is located on the east side of U.S. 42 1 in the City of Cwn~el, H&dton Count): Indiana. C~~rrentl~ the site is v~cant with only rough grading and a row of curbing along the west side. This lot is located at the North West comer of the oveld development known as K'eston Pointe Retd Center. Utdities including stornlwater and saitaiy have been stubbed to the site for coru~ection. The proposed constniction wdl include a 7,900 sf retd building its associated parlung and utilities. Water qualtty wdl be provided by an Aqua-swirl AS-2 for the proposed conditions prior to the release into the existing underground pipe network Existing Conditions: (Appendix B) The existing site curre~ltlydrins through sheet flow from two basins. Basin A flow.; to the west and into an existing endsection located on the site. Stormwater entering the endsection flows south and eventually drains into the overall site pond. Basin B flons east and south to an existing pavement inlet. Flow entering the inlet will flow slightly east and south through an existing underground pipe network, and wdl eventually drain into the overall site pond. Both basins are prima-ily gms and bxe earth with a five foot concrete sidewalk running along the north edge of the site. This walk is the only impervious we'l in the two basins. The 10-Yew total lunoff from the site is 1.34 cfs. Existinz Soil Types: Brooks ton (Br) Silty Clay Loam.. .................... .Type B G-osby (G-A) Silty Clay Loam.. .......................Type .. C 07- 170 - Drainage Report Proposed Conditions: (Appendix C) Ile proposed const~~lction calls for a 7,965 sf retail building its ,~sociated p,uking 'lnd ut~lities, see Proposed Basins Map C1. Run-off from the site will drain through the proposed underground pipe network to the existing inlet located at the southeast corner of the lot. Fronl the inlet stormnvrater n~n-off ud flow south to the existing oved site pond, Lake 1. Please see the attached drainage repolt for Weston Pointe Section 1, prep,u-ed by Ch~isto~her M Figueroa at Stoeppelwerth and Associates on December 15, 2003 and revised March 17, 2004. Also see the included Post Developed ICPR Basins. This site is part of the 10.20 Acre Basin 608. This basin WCE developed expecting a fudy developed co~mnercial site. A curve number of 90 wa used for the entire site and a composite C value of 0.85. Composite C values for this site are calculated as 0.63, 0.61, 0.64, 0.82 and 0.63 with an overed value of 0.70. Time of concentration values are the mini~nuu~l allowable at 5.0 minutes. These values meet the design st.mdards assuuned while designing the site pond. Ple'lse refer to the attached Proposed Drainage Basins ehbit on page CI that oultlules the proposed watersheds for each proposed and existing inlet. Interconnected pipes were designed with the Rational Method, dnd sized for the IO-year frequency rainfall event. Total site nm-off in the proposed condition is 5.33 cfs. Analysis Method: Storm Sewer Conlpu~tations: Computations for stornl sewers to be constructed for the proposed site during this phase of the development have been completed. ?he interconnected pipes were designed with the Rationd Method, and sized for the IO-year frequency raitdall event. 11ese conlputations xe shown on in Appe~idix C The following sun~rnarizes the results of the analysis: Ket~un Interval = 10 years Contributing Basins = see page C1 Rational Runoff Coefficient, C = see page C2 Time of Concentration, Tc = assumed 5 I~. Rainfall Intensity, i = see page C3 Total Runoff, Q = CIA Pipe Fill1 Capacity = (1.49/n)(pdJ/4)(( pdJ/4)/( pd))'j(s)G5 n = Manning's Roughness Coefficient = 0.013 for RCP Pipes d = Diameter of Pipe (feet) s = Slope of Pipe Water Ouality: (Appendix E) VIrater qiiahty n7as determined using the w-ater q~~ality volunle methodology. A corresponding CLIIT~ Number (CNwq) is compi~ted utilizing the following equation: CNwq = 1000 / (10 + 5P + 10Qa- 10 (Qa- 1.25QaP) ) Rv = 0.05 + 0.009 (I) CNwq = curve number for water quality storm event P = 1" (rainfall for water quality storm event) Qa = runoff volume, in i~lches = 1" x Rv = Rv (inches) Rv = volumetric runoff coefficient I is the percent impervious cover A CNwq WE computed to be 97 (see Appendix E). A depth of 1" and duration of 24 holm mras used in the SCS Tpe I1 stonn event. The resudts gave a peak flow of 0.46 cfs. See VIrinTR-20 input and results in Appendix E. An Aqua-snlrl AS-2 capable of treating a peak flow of l.Ocfs was chosen to treat the flow. Summary: The proposed design wdl ensure proper dr&unage by co~lvejin~ storm water at an adequate velocity through the proposed pipe network toward the dry detention. As a result, the storm water design effectively manages the runoff from the site without bul-dering downstre;un property owners. 07- 170 - Drainage Report Appendix A Maps 07- 170 - Drainage Report WESTON POINTE - LOT 3 U.S. 42 1 & WESTOIV POINTE DRIVE CARMEL, INDIANA ".. f 31 7-244-1 969 U.S. 42 1 & WESTOIV POINTE DRIVE CARMEL, INDIANA f 31 7-244-1 969 Appendix B Existing Conditions 07- 170 - Llrainage Report Exising Conditions CIVII Designs Project No 07-1 70 Project Weston Polnte Retall Center - Lot 3 Location U S 421 & Westor) Polnte Dr~ve Descr~pt~on Exisltng Cornposlte C Cornputatlons Runoff Coefficient lrnperv~ous Area = 0 90 Greenspace = 0 20 Gravel~Stone = 0 80 BASINS By MAT Date 611 112007 Checked JMP Date 611 112007 Total Site lrnpervlous Area Stone (ftA2) 0 Time of ConcentrationlTravel Time Worksheet Civil Designs Project No. 07-1 70 Project Weston Pointe Retail Center - Lot 3 Location U.S. 421 & Weston Pointe Drive Description Existing Time of Concentration - Basin A Basin A SHEET FLOW (Applicable to T, only) Segment ID 1. Surface description .............................. 2. Manning's roughness coefficient, n .......... 3. Flow length, L (total L 5 300 ft) ............... fi 4. two-year, 24-hour rainfall, P2 .............................. in 5. Land slope, s ................................... fWft 6. T, = [0.007(n~)~~~]l[~,~~~s~.Compute "] T, .......... hr n source: P2 source: SHALLOW CONCENTRATED FLOW Segment ID 7. Surface description (paved or unpaved) .......... 8. Flow length, L ................................... fi 9. Watercourse slope, s .............................. ft/fi 10. Average velocity, v .............................. ft/s 11. TI = (Llv)l3600 Compute T, .......... hr v = 20.3282(s)'.~ for paved surfaces v = 16.1345(s)~.for ~ unpaved surfaces CHANNEL FLOW 12. Cross sectional flow area, a 13. Wetted perimeter, P,, 14. Hydraulic radius, r = alp,(, 15. Channel slope, s .... 16. Manning's roughness coefficient, n 17. v = (1 .49r2'3s"2)ln 18. Flow length, L 19. TI = (Uv)13600 n source: 20. Total Time of Concentrationflravel Time Segment ID ......................... ft ' ................... ... .......... ft Compute r .......... fi ................... ........... ft/ft ............... Compute v .......... fWs ......................... ft Compute T, .......... hr By MAT Date 0611 112007 Checked JMP Date 0611 112007 ...................................... hours = 0.19 minutes = 11.54 B - C Unpaved 8 1 0.012 2.25 0.010 Basin A 07-170 - Tc Worksheet.xls Total 0.010 Time of ConcentrationlTravel Time Worksheet Civil Designs Project No. 07-1 70 Project Weston Pointe Retail Center - Lot 3 Location U.S. 421 & Weston Pointe Drive Description Existing Time of Concentration - Basin B Basin B SHEET FLOW (Applicable to T, only) Segment ID 1. Surface description .............................. 2. Manning's roughness coefficient, n .......... 3. Flow length, L (total L 5 300 ft) ............... ft 4. two-year, 24-hour rainfall, P, .............................. in 5. Land slope, s ................................... ftfft 6. T, = [o.oo~(~L)@~~]/[P~~s~~] Compute T, .......... hr n source: PS source: SHALLOW CONCENTRATED FLOW Segment ID 7. Surface description (paved or unpaved) .......... 8. Flow length, L ........................ ........... ft 9. Watercourse slope, s .............................. ftfft 10. Average velocity, v .............................. ft/s 11. T, = (Uv)l3600 Compute T, .......... hr v = 20.3282(s)' for paved surfaces v = 16.1 345(s)05 for unpaved surfaces CHANNEL FLOW 12. Cross sectional flow area. a 13. Wetted perimeter, P, 14. Hydraulic radius, r = alp,., 15. Channel slope, s ....... 16. Manning's roughness coefficient, n 17, v = (1 .49rz3~"2)ln 18. Flow length, L 19. T, = (Llv)/3600 n source: 20. Total Time of Concentration/Travel Time Segment ID ......................... ft2 ........................ ... ..... ft Compute r .......... ft ...................................... ftfft ............... Compute v .......... ft/s ......................... ft Compute T, .......... hr By MAT Date 0611 112007 Checked JMP Date 0611 112007 ...................... .. ............................. hours = 0.31 minutes = 18.42 Unpaved Basin B 07-170 - TG Worksheet.xls Total 0.000 Storm Drain Flow Tabulation Form Civil Designs Project No. Project Location Description 07-1 70 Weston Pointe Retail Center - Lot 3 U.S. 421 & Weston Pointe Drive Rational Flow Worksheet By MAT Date 611 112007 Checked JMP Date 611 112007 Design Storm Frequency = 10-Year COEFFICIENT Rational Runoff - 10-Year 07-170 - Storm Sewer Design Worksheet.xls Appendix C Proposed Conditions 07- 170 - Drainage Report Proposed Conditions (1 CIVII Project Deslgns Project No Weston 07-1 70 Polnte Retall Center - Lot 3 Date By 61812007 MAT Locat~on U S 421 & Weston Polnte Dr~ve Descrrpt~on Proposed Cornpos~te C Computations Checked .IMP Date 61812007 Runoff Coefflclent 0.90 0 20 0 80 Greenspace Stone Total Total Cornpos~te lrnperv~ous Area Greenspace (ftA2) Storm Drain Flow Tabulation Form Civil Dosigns Pro)oct No 07-1 70 Project Woston Poirrlu Rul.lll Conlel- Lot 3 Lncation U.S. 421 8 Wosloo Paint" Olive Descrlj,tiul~ Slornl Sowor Slrlng Cornpuln:~a!ls By MAT Dalo iilO/ZOC/ Clieckod JMP Dalo blB12007 Storm Sower - 10-Yoar 07-170 -Storm Sewer Design Workshootxls Appendix D Inlet Capacity Worksheets 07- 170 - Dr'ainage Report Discharge vs Depth On Grate Discharge vs Depth On Grate Discharge vs Depth Grate Appendix E Water Quality 07- 170 - Drainage Report Civil Design Porject No. 07-1 70 Project Name Weston Pointe Retail Center - Lot 3 Location U.S. 421 & Weston Pointe Drive Description Proposed Water Quality Curve Number By: MAT Date: 6/8/2007 Checked: JMP rm! IMPERVIOUS Date: 6/8/2007 WQV = (P) (Rv) (A) 12 CNwq = 1000 10+5~+10Qa-0(1 Qa2+1 .25QaP)"0.5 Total Site Pervious Building Impervious Total Total Curve Number )'tf ((ft') (ft") (f t') (Acres) CN 15389 0 37770 53159 1.22 87.29 Rv WQV CNwq Water Quality Name of printed page f~ile: C:\Program Files\USDA\WinTR20\07-170 - Water Quality.out Area or Drainage Rain Gage ~~~~ff ------------ peak ~l~~ Reach Area ID 01- Amount %levation Time Rate Rate Identifier (sq mi) Location (in) ( ft ) (nr) (cfs) (cs~) Site 0.002 OUTLET 0.002 WinTR-20 Version 1.0 Area or Dralnage ----------- Peak Flow by Storm ----------- Reach Area Alternate 1.0" 24Hr identifier (sq rnli (cfs) (cfs) (cf s) (cfs! icf s) Site 0.190E-02 OUTLET 0.190E-02 WinTR-20 Version 1.0 WinTR-20: Version 1.0 Water Quality SUB -AREA : Site Outlet STORM ANALYSIS : 1.0" 24Hr RAINFALL DISTRIBUTION: 24. OHr 0. ,064 ,181 .856 ,953 GLOBAL OUTPUT: 1 .05 1. 24. OHr 2 .05 YNNhW NNNNNN (1) As recommended by the Center for Watershed Protection and most municipalities, the Aqua-SwirlTN provides full treatment of the "first flush," while the peak design storm is diverted and channeled through the main conveyance pipe. Connections to larger pipe diameters are available at an additional cost, please refer to your local representative for more information. (2) Many regulatory agencies are establishing "water quality treatment flow rates" for their areas based on the initial movement of pollutants into the storm drainage system. The treatment flow rate of the Aqua-SwirlTN system is engineered to meet or exceed the local water quality treatment criteria. This "water quality treatment flow rate" typically represents approximately 90% to 95% of the total annual runoff volume. 'The design and orientation of the qua-swirl'" Concentrator generally enta~ls some degree of custornization. For assistance in design and specific sizing using historical rainfall data, please refer to Joe O'Brien, ENTEL, Inc. at (734) 657-3839 or go to our web site for more information at www.AguaSh~eldInc~c~om~ CAD details and specifications are available upon request.