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Home My WebLink AboutSW4231002_Stormwater Report_20240208 Stormwater Impact Analysis for Dollar Tree 5744 Old US Highway 52 Welcome, North Carolina February 7, 2024 Prepared for: Cedar Run Capital, LLC 2405 Nash Street N Wilson, North Carolina 27896 PRINT NAME: Josh Crumpler, P.E. 49/ SIGNATURE: ( `_AL `- 0" Z_ , .4 CRv REGISTRATION NO. PE-034994 """""�� CRUMPLER Consulting Services, PLLC Prepared by Grumpier Consulting Services, PLLC 2308 Ridge Road, Raleigh, North Carolina 27612 p 1919.413-1704 CRUMPLER Consulting Services, PLLC TABLE OF CONTENTS 1.0 STORMWATER NARRATIVE 2 2.0 DESIGN DATA AND METHODOLOGY 3 3.0 PRE-DEVELOPMENT STORMWATER RUN-OFF 4 4.0 POST-DEVELOPMENT STORMWATER RUN-OFF 5 List of Appendices Appendix A— IDF Rainfall Data Appendix B — SCM Sizing Calculations and Supplement EZ Form Appendix C — Pre/Post Development Peak Flow Tables (2-yr, 10-yr, and 100-yr) Appendix D — Drainage Area Maps 2308 Ridge Road I Raleigh, NC 27612 I p:919-413-1704 I e:josh@crumplerconsulting.com 1.0 STORMWATER NARRATIVE Cedar Run Capital LLC is proposing to construct a commercial building on a 1.38 acre parcel located at 5744 Old US Highway 52 in Welcome, North Carolina that zoned Heavy Commercial (HC). This report represents the stormwater management design and hydrologic model results for the proposed project. As part of the stormwater design, Crumpler Consulting is proposing the installation of a wet detention basin. The wet detention basin has been designed to control and treat the estimated runoff generated from the first inch of rainfall per the requirements of the Neuse Watershed Nutrient Management Strategy and the NCDEQ's stormwater management design manual. The wet detention facility is anticipated to attenuate the peak flow rates for the 2-year, 10-year, and 100-year 24-hour storm events in accordance with NCDEQ's requirements. The nitrogen loading rates have been evaluated as part of this design and are anticipated to be reduced to acceptable rates through treatment by the detention facility and buy down methods. The existing parcel did have minimal existing impervious surfaces that included an existing driveway which totaled 16,631sf. The proposed impervious surface consists of the warehouse building, parking lot, driveways, and sidewalks. The proposed impervious area will total 35,250sf. The proposed grading conveys the majority of the runoff to the southeastern corner of the site, where the runoff is collected in a wet detention basin that discharges to the southeast side of the site. The Post-Development Drainage Map shows the stormwater grading and drainage plan and associated details. Page 2 February 7, 2024 2.0 DESIGN DATA AND METHODOLOGY The design of the proposed stormwater facilities was performed in accordance with the NCDEQ Stormwater SCM Manual. The site was designed to meet Runoff Treatment by utilizing a wet detention basin. It was sized using both Parts `B' and 'C' of the stormwater design manual along with the Supplement-EZ form provided by NCDEQ. In addition to the NCDEQ Stormwater SCM Manual, the Wet Pond was analyzed using Hydraflow Hydrographs. This software is a computer modeling software package, was used for the analysis of stormwater routing and hydrology of the existing and proposed watersheds. The hydrology calculations were performed using the Modified Rational Method and TR-55 methods. Franklin County lies within the Type II rainfall distribution. The rainfall amounts for the site were obtained from National Oceanic and Atmospheric Administration (NOAA) and are included in Appendix A. The stormwater analyses performed for this project include the 2-year, 10-year, and 100-year, 24-hour storm events. The Soil Survey of Davidson County, North Carolina, completed by the National Resource Conservation Service (NRCS), was reviewed for general information on the soils within the site area. Page 3 February 7, 2024 3.0 PRE-DEVELOPMENT STORMWATER RUNOFF The pre-development drainage areas were determined using site visits, visual observations, and surveyed topographic data. The peak flow rates for the specified storm events are based on topography, land use cover (such as open space, grass, woods), and soil type. Two drainage points were selected for analysis. The existing 1.38-acre watershed was modeled in HydraFlow as one subcatchment, as described below. Refer to Appendix F of this report for the pre-development watershed map. • Drainage Area 1 Drainage Area 1 is 1.38 acres and drains to the southeast corner of the property. A time of concentration was calculated and was found to be approximately 5 minutes. Therefore, 5 minutes was estimated as the time of concentration for this subcatchment. The HydroFlow analysis can be found in Appendices. The table below summarizes the hydrologic model results for pre-development peak flow rates of the existing 1.38-acre watershed. PRE-DEVELOPMENT STORMWATER RUNOFF STORM EVENT PRE-DEVELOPMENT PEAK FLOW 2-YEAR 2.667 CFS 10-YEAR 3.448 CFS 100-YEAR 4.147 CFS Page 4 February 7, 2024 4.0 POST-DEVELOPMENT STORMWATER RUNOFF An analysis of the post-development runoff was performed using the same methods, parameters, and assumptions as described in the pre-development analysis above. Based upon the calculations, the project reduces the nitrogen loading to acceptable levels for buy-down and does not create an increase in the peak runoff rate for the 2-year,10-year, and 100-year storm events. This will be achieved by constructing appropriate SCMs. The proposed site was divided into two subcatchments for post-development analysis. The subcatchments are described below. Refer to Appendix F of this report for the post-development watershed map. • Drainage Area 1 Drainage Area 1 is 1.05 acres and includes runoff is treated by the wet detention facility. Runoff that is treated by the wet detention facility is collected in a stormdrainage system and discharged overland in the southeast corner of the site. A time of concentration was calculated and was found to be lower than 5 minutes. Therefore, 5 minutes was estimated as the time of concentration for this subcatchment. • Drainage Area 2 (Bypass) Drainage Area 2 is 0.33 acres and drains offsite to the east bypassing the wet detention facility. A time of concentration was calculated and was found to be lower than 5 minutes. Therefore, 5 minutes was estimated as the time of concentration for this subcatchment. The HydraFlow analysis can be found in Appendices. The follow table summarizes the hydrologic model results for post-development peak flow rates of the 1.38-acre watershed. POST-DEVELOPMENT STORMWATER RUNOFF TOTAL TOTAL STORM EVENT POST-DEVELOPMENT POST-DEVELOPMENT PEAK FLOW PEAK FLOW WITH OUT SCM WITH SCM 2-YEAR 4.261 CFS 0.725 CFS 10-YEAR 5.509 CFS 0.935 CFS 100-YEAR 6.625 CFS 1.123 CFS Page 5 February 7, 2024 APPENDIX A IDF Rainfall Data Page 6 February 7, 2024 22 Hydraflow Rainfall Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2023 Wednesday,02/7/2024 Return Intensity-Duration-Frequency Equation Coefficients(FHA) Period (Yrs) B D E (N/A) 1 0.0000 0.0000 0.0000 2 67.0277 12.7000 0.8729 3 0.0000 0.0000 0.0000 5 68.0041 12.5000 0.8280 10 69.9702 12.5000 0.8066 25 61.1512 11.3000 0.7474 50 54.6664 10.4000 0.7036 100 47.1993 9.1000 0.6554 File name:Welcome.IDF Intensity= B/(Tc+ D)^E Return Intensity Values(in/hr) Period (Yrs) 5 min 10 15 20 25 30 35 40 45 50 55 60 1 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2 5.46 4.39 3.69 3.19 2.82 2.53 2.30 2.11 1.95 1.81 1.69 1.59 3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5 6.36 5.16 4.37 3.81 3.38 3.05 2.78 2.56 2.37 2.22 2.08 1.96 10 6.95 5.68 4.83 4.22 3.76 3.40 3.11 2.87 2.66 2.49 2.34 2.21 25 7.59 6.22 5.31 4.66 4.17 3.79 3.48 3.22 3.01 2.82 2.66 2.52 50 7.98 6.55 5.61 4.95 4.44 4.05 3.73 3.47 3.24 3.05 2.89 2.74 100 8.33 6.83 5.86 5.18 4.67 4.27 3.95 3.68 3.45 3.26 3.09 2.94 Tc=time in minutes.Values may exceed 60. Precip.file name:Sample.pcp Rainfall Precipitation Table (in) Storm Distribution 1-yr 2-yr 3-yr 5-yr 10-yr 25-yr 50-yr 100-yr SCS 24-hour 0.00 2.20 0.00 3.30 4.25 5.77 6.80 7.95 SCS 6-Hr 0.00 1.80 0.00 0.00 2.60 0.00 0.00 4.00 Huff-1st 0.00 1.55 0.00 2.75 4.00 5.38 6.50 8.00 Huff-2nd 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Huff-3rd 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Huff-4th 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Huff-Indy 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Custom 0.00 1.75 0.00 2.80 3.90 5.25 6.00 7.10 APPENDIX B SCM Sizing Calculations, Dissipator Pad Sizing, and Supplement EZ Form Page 7 February 7, 2024 0, 1k 1-ct - uc (,.....e _ Pc- /iZ - 1 -- n;,1 : _ 1 - tot ,10I « cd - / c,,(, 31 O- . f. i.v 5 :\€ : 0 J6wc-7 - 22i LISo54- flv1}- SCA : 3 1 / 8S ° SI- 5:)tL,0,11C- - 280J 5+- A " 113\fec"3C , 3*Oo5l- 5 ., ; 1a, .,S _ / v, oo) 3 f 135, 2A'v j NO- �,^e---(A- St A04 = 35, 2-50 - /�,031Sf = l $ , G15 ) -- ' 31 , 85v5 � CIO '2-) a „,, ,,f-f_ ‘j . I .).._ e ., e-, : ,f.. 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S- 0 --) 7 cf5 a = J _ -r v _ $ 11 2Z- _ [ D 1 37/3Loo — 3 . o 3a, S T Q .-77 ` Y Drainage Area Drainage Area 1 (SF) Drainage Area 2 (SF) Total Drainage Area 45,671 14,356 On-Site Drainage Area 45,671 14,356 Off-Site Drainage Area 0 0 Proposed Impervious Area 31,850 3,400 Impervious Area 69.7% 23.7% Impervious** Surface Area Drainage Area 1 (SF) Drainage Area 2 (SF) Buildings 10,000 Streets 19,050 3,400 Parking 0 0 Sidewalks 2,800 Existing BUA 0 0 Total 31,850 3,400 MAIN POOL STORAGE TABLE Stage SURFACE AREA(SF) Volume (CF) 857 544 0 858 874 709 859 1,268 1,071 860 1,719 1,494 861 2,226 1,973 862 2,790 2,508 Total 7,755 FOREBAY STORAGE TABLE Stage SURFACE AREA(SF) Volume (CF) 860 272 0 861 502 797 862 788 917 Total 1,714 TEMPORARY POOL STORAGE TABLE Stage SURFACE AREA(SF) Volume (CF) 862 3,578 - 863 5,250 2,690 864 6,229 5,732 . Total 8,422 V I I limo s■••ram• V I gym` V V V gym• % ■ • \V lbw OJECT INFORMATION 1 Project Name Dollar Tree-Welcome, NC 2 I Project Area (ac) 1.38 3 (Coastal Wetland Area (ac) 0 4 (Surface Water Area (ac) 0 5 lIs this protect High or Low Density? Both High and Low Density , 6 Does this project use an off-site SCM? No IMPLIANCE WITH 02H .1003(4) 7 Width of vegetated setbacks provided (feet) 5 8 'Will the vegetated setback remain vegetated? Yes 9 ,If BUA is proposed in the setback, does it meet NCAC 02H.1003(4)(c-d)? N/A 10 I Is streambank stabilization proposed on this project? No IMBER AND TYPE OF SCMs: 11 Infiltration System _ 12 ,Bioretention Cell 13 Wet Pond 1 14 .Wet Wetland 15 Permeable Pavement 16 Sand Filter 17 Rainwater Harvesting (RWH) 18 Green Roof 19 Level Spreader-Filter Strip(LS-FS) !0 Disconnected Impervious Surface(DIS) !1 Treatment Swale 2 _Dry Pond !3 StormFdter !4 Silva Cell 15 Bayfilter !6 Filterra i I FORMS LOADED I SIGNER CERTIFICATION '7 !Name and Title Joshua Crumpler, PE !8 'Organization: Crumpler Consulting Services, PLLC !9 Street address 2308 Ridge Road S0 City, State,Zip: Raleigh, NC 27612 11 Phone number(s): 919-413-1704 )2 Email: josh@crumplerconsulting.com Certificabon 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. pesianer `\I\\111111111//// .� Q.� • • li •. y • •; ; �- ,,,-�'1L S-9esigner • ▪ s• •034A9 �,� cr - •••�NGIN •.•• Q . •�C/ •••••.. �. •, ,q R -,,, A m c 2 � ( 2. `I'//j11111,00- Seal Date DRAINAGE AREAS r5 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? _ Yes 4 If so,number of low density drainage areas _ 1 Is all/part of this project subject to previous rule versions? No FORMS LOADED DRAINAGE AREA INFORMATION Entire Site 1 LD 1 4 Type of SCM Wet Pond Low Density 5 Total drainage area(sq ft) 60037 45681 14356 _ 6 Onsite drainage area(sq ft) 60037 45681 14356 7 Offsite drainage area(sq ft) 0 0 0 8 Total BUA in project(sq ft) 35250 sf 31850 sf 3400 sf New BUA on subdivided lots(subject to 9 permitting)(sq ft) New BUA not on subdivided lots(subject to 10 permitting)(sf) 35250 sf 31850 sf 3400 sf 11 Offsite BUA(sq ft) 12 Breakdown of new BUA not on subdivided lots: -Parking(sq ft) 22450 sf 19050 sf 3400 sf -Sidewalk(sq ft) 2800 sf 2800 sf -Roof(sq ft) 10000 sf 10000 sf -Roadway(sq ft) -Future(sq ft) -Other,please specify in the comment box below(sq ft) New infiltrating permeable pavement on 13 subdivided lots(sq ft) New infiltrating permeable pavement not on 14 subdivided lots(sq ft) Existing BUA that will remain(not subject to 15 permitting)(sq ft) 16 Existing BUA that is already permitted(sq ft) 17 Existing BUA that will be removed(sq ft) 16631 sf 16631 sf 18 Percent BUA 70% 69% 24% 19 Design storm(inches) 1.0 in 1.0 in 1.0 in 20 Design volume of SCM(cu ft) 2572 cf 21 Calculation method for design volume Simple Method ADDITIONAL INFORMATION Please use this space to provide any additional information about the 22 drainage area(s): WET POND 1 Drainage area number 1 I 2 Minimum required treatment volume(Cu ft) 2572 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 Does the SCM have retaining walls,gabion walls or other 6 engineered side slopes? No 7 Are the inlets,outlets,and receiving stream protected from erosion Yes (10-year storm)? 8 Is there an overflow or bypass for inflow volume in excess of the Yes design volume? 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 If the SCM is on a single family lot,does(will?)the plat comply with 13 General MDC(10)? 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 16 Does the SCM follow the device specific MDC? Yes 17 Was the SCM desi ned b an NC licensed rofessional? 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 856.50 removal)(fmsl) 21 Elevation of the main pool bottom(top of sediment removal)(fmsl) 857.00 22 Elevation of the bottom of the vegetated shelf(fmsl) 861.00 23 Elevation of the permanent pool(fmsl) 862.00 24 Elevation of the top of the vegetated shelf(fmsl) 862.00 25 Elevation of the temporary pool(fmsl) 862.41 26 Surface area of the main permanent pool(square feet) 2790 27 Volume of the main permanent pool(cubic feet) 7755 cf 28 Average depth of the main pool(feet) 3.09 ft 29 Average depth equation used Equation 2 30 If using equation 3,main pool perimeter(feet) 31 If using equation 3,width of submerged veg.shelf(feet) 32 Volume of the forebay(cubic feet) 1714 cf 33 Is this 15-20%of the volume in the main pool? Yes 34 Clean-out depth for forebay(inches) 6 in 35 Design volume of SCM(cu ft) 8422 cf 36 Is the outlet an orifice or a weir? Orifice 37 If orifice,orifice diameter(inches) .5 in 38 If weir,weir height(inches) 39 If weir,weir length(inches) 40 Drawdown time for the temporary pool(days) 3 41 Are the inlet(s)and outlet located in a manner that avoids short- Yes circuiting? 42 Are berms or baffles provided to improve the flow path? No 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 ft 47 Slope of vegetated shelf(H:V) 6:1 48 Does the orifice drawdown from below the top surface of the Yes permanent pool? 49 Does the pond minimize impacts to the receiving channel from the 1- Yes yr,24-hr storm? 50 Are fountains proposed?(If Y,please provide documentation that No MDC(9)is met.) 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 _ Bermuda 54i Has a 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 1 4:08 PM 2/7/2024 LOW DENSITY DESIGN REQUIREMENTS FOR LOW DENSITY PROJECTS FROM 02H.1003 1 Is project below density thresholds set forth in the applicable stormwater rule? Yes 2 Does project maximize dispersed flow and minimize channelization of flow? Yes 3 Has the use of piping been minimized per.1003(2)(c)? Yes 4 Side slopes of the vegetated conveyances(H:V) NA 5 Maximum velocity in the vegetated conveyances during the 10-year storm? 6 Are curb outlet swales proposed? No 7 Maximum longitudinal slope of curb outlet swale(s)(%) 8 Bottom width of curb outlet swale(s)(feet) 9 Maximum side slope of curb outlet swale(s)(H:V) 10 Minimum length of curb outlet swale(s)(feet) 11 Are treatment swales used instead of curb outlet swales? 12 Is stormwater released at the edge of the setback as dispersed flow? Yes 13 Have stormwater outlets been designed to prevent downslope erosion? Yes 14 Are variations to rule.1003 proposed? No ADDITIONAL INFORMATION 15 Please use this space to provide any additional information about this low density project: Drainage Pervious Swale BUA Q Slope V,iiow V,,to,i Flow depth Area area (ac) (cfs) (%) (fps) (fps) (ft) (ac) (ac) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 DESIGN OF RIPRAP OUTLET PROTECTION -SINGLE PIPE Single Pipe Outlet Project Dollar Tree Welcome NC Date 7-Feb-24 Project No. 23024 Designer Josh C. Pipe and Flow Data Outlet ID Pond Outlet Pipe diameter 15 in. Pipe slope 1.00% Outlet flowrate 0.9 cfs Outlet velocity 2.0 ft/sec Zone from graph below= 1 Figure 8.06.b.1 25 20 Zone 7 " Zont-6 15 11 10 \ Zone 5 Z-o,e 4 5 - • 2.0¢Jsec " . .1 3 0 Zone 1 0 1 2 3 4 5 6 7 Zone 2 9 10 Pipe diameter(ft) NCDOT Class A Riprap-5'L x 3.75'W x 9"Thick Zone Material Diameter Thickness Length Width 1 Class A 3 9 4 x D(o) 3 x D(o) 2 Class B 6 22 6 x D(o) 3 x D(o) 3 Class I 13 22 8 x D(o) 3 x D(o) 4 Class I 13 22 8 x D(o) 3 x D(o) 5 Class II 23 27 10 x D(o) 3 x D(o) 6 Class II 23 27 10 x D(o) 3 x D(o) 7 Special study required 1.Calculations based on NY DOT method-Pages 8.06.05 through 8.06.06 in NC Erosion Control Manual Linda Rae_Riprap Energy Dissipators.xls 2/7/2024 DESIGN OF RIPRAP OUTLET PROTECTION -SINGLE PIPE Single Pipe Outlet Project Dollar Tree Welcome NC Date 7-Feb-24 Project No. 23024 Designer Josh C. Pipe and Flow Data Outlet ID FES#1 Pipe diameter 15 in. Pipe slope 1.00% Outlet flowrate 3.6 cfs Outlet velocity 4.4 ft/sec Zone from graph below= 1 Figure 8.06.6.1 25 20 Zone 7 " Zont-6 15 i 10 Zone 5 Zone 4 5 • SPC 0 Zone 1 3 0 1 2 3 4 5 6 7 Ztgie 2 9 10 Pipe diameter(ft) NCDOT Class A Riprap-5'L x 3.75'W x 9"Thick Zone Material Diameter Thickness Length Width 1 Class A 3 9 4 x D(o) 3 x D(o) 2 Class B 6 22 6 x D(o) 3 x D(o) 3 Class I 13 22 8 x D(o) 3 x D(o) 4 Class I 13 22 8 x D(o) 3 x D(o) 5 Class II 23 27 10 x D(o) 3 x D(o) 6 Class II 23 27 10 x D(o) 3 x D(o) 7 Special study required 1.Calculations based on NY DOT method-Pages 8.06.05 through 8.06.06 in NC Erosion Control Manual Linda Rae_Riprap Energy Dissipators.xls 2/7/2024 DESIGN OF RIPRAP OUTLET PROTECTION -SINGLE PIPE Single Pipe Outlet Project Dollar Tree Welcome NC Date 7-Feb-24 Project No. 23024 Designer Josh C. Pipe and Flow Data Outlet ID FES#1 Pipe diameter 12 in. Pipe slope 1.00% Outlet flowrate 1.0 cfs Outlet velocity 2.0 ft/sec Zone from graph below= 1 Figure 8.06.b.1 25 20 Zone 7 " Zont-6 15 11 10 Zone 5 Zone 4 5 - ® 2.0-ft/set, 3 0 Zor 1 0 1 2 3 4 5 6 7 Zone 2 9 10 Pipe diameter(ft) NCDOT Class A Riprap-4'L x 3'W x 9"Thick Zone Material Diameter Thickness Length Width 1 Class A 3 9 4 x D(o) 3 x D(o) 2 Class B 6 22 6 x D(o) 3 x D(o) 3 Class I 13 22 8 x D(o) 3 x D(o) 4 Class I 13 22 8 x D(o) 3 x D(o) 5 Class II 23 27 10 x D(o) 3 x D(o) 6 Class II 23 27 10 x D(o) 3 x D(o) 7 Special study required 1.Calculations based on NY DOT method-Pages 8.06.05 through 8.06.06 in NC Erosion Control Manual Linda Rae_Riprap Energy Dissipators.xls 2/7/2024 APPENDIX C Pre/Post Development Peak Flow Tables (2-yr, 10-yr, and 100-yr) Page 8 February 7, 2024 1 Watershed Model Schematic Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk,Inc.v2023 1,15 Otri 4 Project: Welcome-Proposed.gpw Wednesday, 02/7/2024 2 Hydrograph Return Period Recap draflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk,Inc.v2023 Hyd. Hydrograph Inflow Peak Outflow(cfs) Hydrograph No. type hyd(s) Description (origin) 1-yr 2-yr 3-yr 5-yr 10-yr 25-yr 50-yr 100-yr 1 Mod. Rational 3.551 4.591 5.521 PROPOSED POND 2 Reservoir 1 0.017 0.020 0.022 Proposed Pond 3 Mod. Rational 0.710 0.918 1.104 BY-PASS 4 Combine 2,3 0.725 0.935 1.123 COMBINED SITE 5 Mod. Rational 2.667 3.448 4.147 EXISTING SITE Proj. file: Welcome-Proposed.gpw Wednesday, 02/7/2024 3 Hydrograph Summary Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk,Inc.v2023 Hyd. Hydrograph Peak Time Time to Hyd. Inflow Maximum Total Hydrograph No. type flow interval Peak volume hyd(s) elevation strge used Description (origin) (cfs) (min) (min) (cuft) (ft) (cuft) I 1 Mod. Rational 3.551 1 5 2,130 PROPOSED POND 2 Reservoir 0.017 1 15 1,775 1 862.48 2,122 Proposed Pond 3 Mod. Rational 0.710 1 5 426 BY-PASS 4 Combine 0.725 1 10 2,201 2,3 COMBINED SITE 5 Mod. Rational 2.667 1 5 1,600 EXISTING SITE Welcome-Proposed.gpw Return Period: 2 Year Wednesday, 02/7/2024 4 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2023 Wednesday,02/7/2024 Hyd. No. 1 PROPOSED POND Hydrograph type = Mod. Rational Peak discharge = 3.551 cfs Storm frequency = 2 yrs Time to peak = 5 min Time interval = 1 min Hyd. volume = 2,130 cuft Drainage area = 1.050 ac Runoff coeff. = 0.77* Intensity = 4.392 in/hr Tc by User = 5.00 min IDF Curve = Welcome.IDF Storm duration = 2.0 x Tc Target Q =n/a Est. Req'd Storage =n/a *Composite(Area/C)=[(0.730 x 0.95)+(0.320 x 0.35)]/1.050 PROPOSED POND Q (cfs) Hyd. No. 1 --2 Year Q (cfs) 4.00 4.00 3.00 3.00 2.00 2.00 1.00 1.00 0.00 0.00 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Hyd No. 1 Time (min) 5 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2023 Wednesday,02/7/2024 Hyd. No. 2 Proposed Pond Hydrograph type = Reservoir Peak discharge = 0.017 cfs Storm frequency = 2 yrs Time to peak = 15 min Time interval = 1 min Hyd. volume = 1,775 cuft Inflow hyd. No. = 1 - PROPOSED POND Max. Elevation = 862.48 ft Reservoir name = Pond Max. Storage = 2,122 cuft Storage Indication method used. Proposed Pond Q (cfs) Hyd. No. 2 --2 Year 0 (cfs) 4.00 4.00 3.00 3.00 2.00 2.00 1.00 1.00 0.00 0.00 0 300 600 900 1200 1500 1800 2100 2400 2700 3000 Time (min) Hyd No. 2 Hyd No. 1 II 1 1 1 1 1 Total storage used = 2,122 cuft Pond Report 6 Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2023 Wednesday,02/7/2024 Pond No. 1 - Pond Pond Data Contours-User-defined contour areas.Conic method used for volume calculation.Begining Elevation=862.00 ft Stage/Storage Table Stage(ft) Elevation(ft) Contour area(sqft) Incr.Storage(cuft) Total storage(cuft) 0.00 862.00 3,578 0 0 1.00 863.00 5,250 4,387 4,387 2.00 864.00 6,229 5,732 10,119 Culvert/Orifice Structures Weir Structures [A] [B] [C] [PrfRsr] [A] [B] [C] [D] Rise(in) = 12.00 1.00 0.00 15.00 Crest Len(ft) = 9.42 10.00 0.00 0.00 Span(in) = 12.00 1.00 0.00 15.00 Crest El.(ft) = 864.00 864.50 0.00 0.00 No.Barrels = 1 1 0 0 Weir Coeff. = 3.33 3.33 3.33 3.33 Invert El.(ft) = 858.00 862.00 0.00 0.00 Weir Type = 1 Rect --- --- Length(ft) = 30.00 1.00 0.00 0.00 Multi-Stage = Yes No No No Slope(%) = 1.00 1.00 0.00 n/a N-Value = .013 .013 .013 n/a Orifice Coeff. = 0.60 0.60 0.60 0.60 Exfil.(in/hr) = 0.000(by Wet area) Multi-Stage = n/a No No No TW Elev.(ft) = 0.00 Note:Culvert/Orifice outflows are analyzed under inlet(ic)and outlet(oc)control. Weir risers checked for orifice conditions(ic)and submergence(s). Stage(ft) Stage/ Discharge Elev(ft) 2.00 864.00 1.80 863.80 1.60 863.60 1.40 863.40 1.20 863.20 1.00 863.00 0.80 862.80 0.60 862.60 0.40 862.40 0.20 862.20 0.00 862.00 0.000 0.004 0.008 0.012 0.016 0.020 0.024 0.028 0.032 0.036 0.040 Total Q Discharge(cfs) 7 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2023 Wednesday,02/7/2024 Hyd. No. 3 BY-PASS Hydrograph type = Mod. Rational Peak discharge = 0.710 cfs Storm frequency = 2 yrs Time to peak = 5 min Time interval = 1 min Hyd. volume = 426 cuft Drainage area = 0.330 ac Runoff coeff. = 0.49* Intensity = 4.392 in/hr Tc by User = 5.00 min IDF Curve = Welcome.IDF Storm duration = 2.0 x Tc Target Q =n/a Est. Req'd Storage =n/a *Composite(Area/C)=[(0.078 x 0.95)+(0.252 x 0.35)]/0.330 BY-PASS Q (cfs) Hyd. No. 3 --2 Year Q (cfs) 1.00 1.00 0.90 0.90 0.80 0.80 0.70 0.70 0.60 0.60 0.50 0.50 0.40 0.40 0.30 0.30 0.20 0.20 0.10 0.10 0.00 0.00 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Hyd No. 3 Time (min) 8 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2023 Wednesday,02/7/2024 Hyd. No. 4 COMBINED SITE Hydrograph type = Combine Peak discharge = 0.725 cfs Storm frequency = 2 yrs Time to peak = 10 min Time interval = 1 min Hyd. volume = 2,201 cuft Inflow hyds. = 2, 3 Contrib. drain. area = 0.330 ac COMBINED SITE Q (cfs) Hyd. No. 4 --2 Year Q (cfs) 1.00 I 1.00 0.90 0.90 0.80 0.80 0.70 0.70 0.60 0.60 0.50 0.50 0.40 0.40 0.30 0.30 0.20 0.20 0.10 0.10 0.00 - 0.00 0 180 360 540 720 900 1080 1260 1440 1620 1800 1980 Time (min) Hyd No. 4 Hyd No. 2 Hyd No. 3 9 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2023 Wednesday,02/7/2024 Hyd. No. 5 EXISTING SITE Hydrograph type = Mod. Rational Peak discharge = 2.667 cfs Storm frequency = 2 yrs Time to peak = 5 min Time interval = 1 min Hyd. volume = 1,600 cuft Drainage area = 1.380 ac Runoff coeff. = 0.44* Intensity = 4.392 in/hr Tc by User = 5.00 min IDF Curve = Welcome.IDF Storm duration = 2.0 x Tc Target Q =n/a Est. Req'd Storage =n/a *Composite(Area/C)=[(0.380 x 0.95)+(1.000 x 0.25)]/1.380 EXISTING SITE Q (cfs) Hyd. No. 5 --2 Year Q (cfs) 3.00 3.00 2.00 2.00 1.00 1.00 0.00 0.00 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Hyd No. 5 Time (min) 10 Hydrograph Summary Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk,Inc.v2023 Hyd. Hydrograph Peak Time Time to Hyd. Inflow Maximum Total Hydrograph No. type flow interval Peak volume hyd(s) elevation strge used Description (origin) (cfs) (min) (min) (cuft) (ft) (cuft) I 1 Mod. Rational 4.591 1 5 2,755 PROPOSED POND 2 Reservoir 0.020 1 15 2,248 1 862.63 2,744 Proposed Pond 3 Mod. Rational 0.918 1 5 551 BY-PASS 4 Combine 0.935 1 10 2,799 2,3 COMBINED SITE 5 Mod. Rational 3.448 1 5 2,069 EXISTING SITE Welcome-Proposed.gpw Return Period: 10 Year Wednesday, 02/7/2024 11 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2023 Wednesday,02/7/2024 Hyd. No. 1 PROPOSED POND Hydrograph type = Mod. Rational Peak discharge = 4.591 cfs Storm frequency = 10 yrs Time to peak = 5 min Time interval = 1 min Hyd. volume = 2,755 cuft Drainage area = 1.050 ac Runoff coeff. = 0.77* Intensity = 5.679 in/hr Tc by User = 5.00 min IDF Curve = Welcome.IDF Storm duration = 2.0 x Tc Target Q =n/a Est. Req'd Storage =n/a *Composite(Area/C)=[(0.730 x 0.95)+(0.320 x 0.35)]/1.050 PROPOSED POND Q (cfs) Hyd. No. 1 -- 10 Year Q (cfs) 5.00 5.00 4.00 4.00 3.00 3.00 2.00 2.00 1.00 1.00 0.00 0.00 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Hyd No. 1 Time (min) 12 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2023 Wednesday,02/7/2024 Hyd. No. 2 Proposed Pond Hydrograph type = Reservoir Peak discharge = 0.020 cfs Storm frequency = 10 yrs Time to peak = 15 min Time interval = 1 min Hyd. volume = 2,248 cuft Inflow hyd. No. = 1 - PROPOSED POND Max. Elevation = 862.63 ft Reservoir name = Pond Max. Storage = 2,744 cuft Storage Indication method used. Proposed Pond Q (cfs) Hyd. No. 2 -- 10 Year Q (cfs) 5.00 5.00 4.00 4.00 3.00 3.00 2.00 2.00 1.00 - 1.00 0.00 — 0.00 0 300 600 900 1200 1500 1800 2100 2400 2700 3000 Time (min) Hyd No. 2 Hyd No. 1 II 1 1 1 1 1 Total storage used = 2,744 cuft 13 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2023 Wednesday,02/7/2024 Hyd. No. 3 BY-PASS Hydrograph type = Mod. Rational Peak discharge = 0.918 cfs Storm frequency = 10 yrs Time to peak = 5 min Time interval = 1 min Hyd. volume = 551 cuft Drainage area = 0.330 ac Runoff coeff. = 0.49* Intensity = 5.679 in/hr Tc by User = 5.00 min IDF Curve = Welcome.IDF Storm duration = 2.0 x Tc Target Q =n/a Est. Req'd Storage =n/a *Composite(Area/C)=[(0.078 x 0.95)+(0.252 x 0.35)]/0.330 BY-PASS Q (cfs) Hyd. No. 3-- 10 Year Q (cfs) 1.00 1.00 0.90 0.90 0.80 0.80 0.70 , 0.70 0.60 0.60 0.50 0.50 0.40 0.40 0.30 0.30 0.20 0.20 0.10 0.10 0.00 0.00 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Hyd No. 3 Time (min) 14 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2023 Wednesday,02/7/2024 Hyd. No. 4 COMBINED SITE Hydrograph type = Combine Peak discharge = 0.935 cfs Storm frequency = 10 yrs Time to peak = 10 min Time interval = 1 min Hyd. volume = 2,799 cuft Inflow hyds. = 2, 3 Contrib. drain. area = 0.330 ac COMBINED SITE Q (cfs) Hyd. No. 4-- 10 Year Q (cfs) 1.00 1.00 0.90 0.90 0.80 0.80 0.70 0.70 0.60 0.60 0.50 0.50 0.40 0.40 0.30 0.30 0.20 0.20 0.10 0.10 0.00 ' - 0.00 0 240 480 720 960 1200 1440 1680 1920 2160 2400 Time (min) Hyd No. 4 Hyd No. 2 Hyd No. 3 15 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2023 Wednesday,02/7/2024 Hyd. No. 5 EXISTING SITE Hydrograph type = Mod. Rational Peak discharge = 3.448 cfs Storm frequency = 10 yrs Time to peak = 5 min Time interval = 1 min Hyd. volume = 2,069 cuft Drainage area = 1.380 ac Runoff coeff. = 0.44* Intensity = 5.679 in/hr Tc by User = 5.00 min IDF Curve = Welcome.IDF Storm duration = 2.0 x Tc Target Q =n/a Est. Req'd Storage =n/a *Composite(Area/C)=[(0.380 x 0.95)+(1.000 x 0.25)]/1.380 EXISTING SITE Q (cfs) Hyd. No. 5-- 10 Year Q (cfs) 4.00 4.00 3.00 3.00 2.00 2.00 1.00 1.00 0.00 0.00 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Hyd No. 5 Time (min) 16 Hydrograph Summary Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk,Inc.v2023 Hyd. Hydrograph Peak Time Time to Hyd. Inflow Maximum Total Hydrograph No. type flow interval Peak volume hyd(s) elevation strge used Description (origin) (cfs) (min) (min) (cuft) (ft) (cuft) I 1 Mod. Rational 5.521 1 5 3,313 PROPOSED POND 2 Reservoir 0.022 1 15 2,634 1 862.75 3,301 Proposed Pond 3 Mod. Rational 1.104 1 5 663 BY-PASS 4 Combine 1.123 1 10 3,296 2,3 COMBINED SITE 5 Mod. Rational 4.147 1 5 2,488 EXISTING SITE Welcome-Proposed.gpw Return Period: 100 Year Wednesday, 02/7/2024 17 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2023 Wednesday,02/7/2024 Hyd. No. 1 PROPOSED POND Hydrograph type = Mod. Rational Peak discharge = 5.521 cfs Storm frequency = 100 yrs Time to peak = 5 min Time interval = 1 min Hyd. volume = 3,313 cuft Drainage area = 1.050 ac Runoff coeff. = 0.77* Intensity = 6.829 in/hr Tc by User = 5.00 min IDF Curve = Welcome.IDF Storm duration = 2.0 x Tc Target Q =n/a Est. Req'd Storage =n/a *Composite(Area/C)=[(0.730 x 0.95)+(0.320 x 0.35)]/1.050 PROPOSED POND Q (cfs) Hyd. No. 1 -- 100 Year Q (cfs) 6.00 I 6.00 5.00 5.00 4.00 4.00 3.00 3.00 2.00 2.00 1.00 1.00 0.00 0.00 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Hyd No. 1 Time (min) 18 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2023 Wednesday,02/7/2024 Hyd. No. 2 Proposed Pond Hydrograph type = Reservoir Peak discharge = 0.022 cfs Storm frequency = 100 yrs Time to peak = 15 min Time interval = 1 min Hyd. volume = 2,634 cuft Inflow hyd. No. = 1 - PROPOSED POND Max. Elevation = 862.75 ft Reservoir name = Pond Max. Storage = 3,301 cuft Storage Indication method used. Proposed Pond Q (cfs) Hyd. No. 2-- 100 Year Q (cfs) 6.00 6.00 5.00 5.00 4.00 4.00 3.00 3.00 2.00 2.00 1.00 1.00 0.00 — 0.00 0 300 600 900 1200 1500 1800 2100 2400 2700 3000 Time (min) Hyd No. 2 Hyd No. 1 II 1 1 1 1 1 Total storage used = 3,301 cuft 19 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2023 Wednesday,02/7/2024 Hyd. No. 3 BY-PASS Hydrograph type = Mod. Rational Peak discharge = 1.104 cfs Storm frequency = 100 yrs Time to peak = 5 min Time interval = 1 min Hyd. volume = 663 cuft Drainage area = 0.330 ac Runoff coeff. = 0.49* Intensity = 6.829 in/hr Tc by User = 5.00 min IDF Curve = Welcome.IDF Storm duration = 2.0 x Tc Target Q =n/a Est. Req'd Storage =n/a *Composite(Area/C)=[(0.078 x 0.95)+(0.252 x 0.35)]/0.330 BY-PASS Q (cfs) Hyd. No. 3-- 100 Year Q (cfs) 2.00 2.00 1.00 1.00 0.00 0.00 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Hyd No. 3 Time (min) 20 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2023 Wednesday,02/7/2024 Hyd. No. 4 COMBINED SITE Hydrograph type = Combine Peak discharge = 1.123 cfs Storm frequency = 100 yrs Time to peak = 10 min Time interval = 1 min Hyd. volume = 3,296 cuft Inflow hyds. = 2, 3 Contrib. drain. area = 0.330 ac COMBINED SITE Q (cfs) Hyd. No. 4-- 100 Year Q (cfs) 2.00 2.00 1.00 1.00 0.00 0.00 0 240 480 720 960 1200 1440 1680 1920 2160 2400 Time (min) Hyd No. 4 Hyd No. 2 Hyd No. 3 21 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2023 Wednesday,02/7/2024 Hyd. No. 5 EXISTING SITE Hydrograph type = Mod. Rational Peak discharge = 4.147 cfs Storm frequency = 100 yrs Time to peak = 5 min Time interval = 1 min Hyd. volume = 2,488 cuft Drainage area = 1.380 ac Runoff coeff. = 0.44* Intensity = 6.829 in/hr Tc by User = 5.00 min IDF Curve = Welcome.IDF Storm duration = 2.0 x Tc Target Q =n/a Est. Req'd Storage =n/a *Composite(Area/C)=[(0.380 x 0.95)+(1.000 x 0.25)]/1.380 EXISTING SITE Q (cfs) Hyd. No. 5-- 100 Year Q (cfs) 5.00 5.00 4.00 4.00 3.00 3.00 2.00 2.00 1.00 1.00 0.00 0.00 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Hyd No. 5 Time (min) 22 Hydraflow Rainfall Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2023 Wednesday,02/7/2024 Return Intensity-Duration-Frequency Equation Coefficients(FHA) Period (Yrs) B D E (N/A) 1 0.0000 0.0000 0.0000 2 67.0277 12.7000 0.8729 3 0.0000 0.0000 0.0000 5 68.0041 12.5000 0.8280 10 69.9702 12.5000 0.8066 25 61.1512 11.3000 0.7474 50 54.6664 10.4000 0.7036 100 47.1993 9.1000 0.6554 File name:Welcome.IDF Intensity= B/(Tc+ D)^E Return Intensity Values(in/hr) Period (Yrs) 5 min 10 15 20 25 30 35 40 45 50 55 60 1 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2 5.46 4.39 3.69 3.19 2.82 2.53 2.30 2.11 1.95 1.81 1.69 1.59 3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5 6.36 5.16 4.37 3.81 3.38 3.05 2.78 2.56 2.37 2.22 2.08 1.96 10 6.95 5.68 4.83 4.22 3.76 3.40 3.11 2.87 2.66 2.49 2.34 2.21 25 7.59 6.22 5.31 4.66 4.17 3.79 3.48 3.22 3.01 2.82 2.66 2.52 50 7.98 6.55 5.61 4.95 4.44 4.05 3.73 3.47 3.24 3.05 2.89 2.74 100 8.33 6.83 5.86 5.18 4.67 4.27 3.95 3.68 3.45 3.26 3.09 2.94 Tc=time in minutes.Values may exceed 60. Precip.file name:Sample.pcp Rainfall Precipitation Table (in) Storm Distribution 1-yr 2-yr 3-yr 5-yr 10-yr 25-yr 50-yr 100-yr SCS 24-hour 0.00 2.20 0.00 3.30 4.25 5.77 6.80 7.95 SCS 6-Hr 0.00 1.80 0.00 0.00 2.60 0.00 0.00 4.00 Huff-1st 0.00 1.55 0.00 2.75 4.00 5.38 6.50 8.00 Huff-2nd 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Huff-3rd 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Huff-4th 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Huff-Indy 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Custom 0.00 1.75 0.00 2.80 3.90 5.25 6.00 7.10 APPENDIX D Drainage Area Maps Page 9 February 7, 2024 v, / I ) lI / I 1 I I -- 1 / LEGEND / I // 1 / / \ I 1 / I / I I I A / I I I I / A A EXISTING PROPERTY LINE Et U / / // 1 I \ // / I 1 I I \\ \ I EXISTING ABUTTING PROPERTY LINE 1 7 1 �1 N I l I /// 3! 1 \\ \) /J / / I -\\\\ I EXISTING RIGHT-OF-WAY 'L I_II N I II // �I� \V I I 1 I I II A\V A A OHW OHW EXISTING OVERHEAD POWER LINE =o / I / W _ / I I EXISTING IN RESS/EGR SS EASEMENT I \\ I """��111 CC 2 0 I /II / OI )( 1RDB2107,PG 1803 1 - • vU�"' (I1 ¢ \\ EXISTING ABUTTING PROPERTY LINE U v m M M / /I ,/ \ _/ \ I I O BE REM I I I I \\�\ EXISTING BUILDING SETBACK LINE i c d / / 1 / 1� - _ / I 1 1 I 1 I 1 I \ \V A EXISTING PARKING SETBACK LINE °°' RIM 7258' l / 3 I; /L l t--I I /' I I I \\\V A\ EXISTING EDGE OF PAVEMENT rna WV.IN=883.03' 0 / / I I / I 1 I I / / I I A V` i2 INV.OUT=862.88' I / _. \ \ EXISTING PAVEMENT / I I,F,- h\ I l {I �/ J / // /I / r — — \\\ f/////////////� TO BE REMOVED j / / �J i I / / l Vvy C I GNW� c47) I -4-------vAv�v U I I OHW / �) f 1 \ r/ I / I/ / / A A A V I I / I / I \ I \ \I I I IIj I / /-�vv\\ \\ vvv \ \ I I j �� „Af/,tD��,. I FIBER OPTIC ./ \ AV A I I I O l/r """ \ •' t . E / // ti VAULT / S831g37' u. \ I 11 'mil ese N \ �T T \ T I I I '.•q'A..C.Rp,F I / I \\ \ 6" &\4" PVC PIPE \\I \ 1 I I 1 va� I // \ W/ ELECTRICAL \\ I\ I 1 S WIRES V A l 11 I I 1 SSSSS /� I I j / �•. �� II v \ �\ 1 ISSUED FOR it �N to \ \\ \ , \ I 11 I I CONSTRUCTION I 1 / I I rh I •S \ \ \I \ I �. / 3 ASPHALT Y ® 11 11 2 �` (� PARKING L�T a I f (TO,BE REM VED) w:. / \ \ \ 1 1 11 I U W N N J M l y \ \1 I \\ 1 1 1 11 CO m I �'t�1 ;It 1 I \ \ \ o o I a m / I I . EXISTING BUILDING • I 1 ///11 II / 11 \ 1 1 I rn cb re I 8 0' p (TO BEPREDMOVED) {I � l'I%/ /I // I I II1 all I 1 O a a�F � I� 1 I I I: I 1 • �1�h11 I ;; I / / ; GI I APPROXIMATE LOCATION N I 1_ e � �/; I�I I 1 / / 1 / I I EX.UNKNOWN MATERIAL I 1 _ / '/ / / i I I 1 / / I I I 1 1,--'.- OF SANITARY SEWER MAIN 1 / ��/'/ / I I 1 / 1 1 1 II I OI �1' ~ CONTRACTOR TO VERIFY _ MATERIAL,LOCATION,AND SIZE 42' PRE-DEVELOPMENT DRAINAGE AREA: i i ' / I I 21 Z W Z EX EOP / 1f'- a 0 I / 1.125 AC / I I 1 I �I tY M a O / O O I C=O.44 I I O CO. 07 - W I f / // 1 I / 1 1 1 I a w Z APPROXIMATE LOCATION I / I I I I Z Z OF EX WATER MAIN I _�/ / I �'� / / // I I 1 1 I I w Z CONTRACTOR TO VERIFY 1 / ti I r® �/ I I a LOCATION AND SIZE 11 I /// /I I / � / /// I I 1 1 I I I ii I A r e`/) 1 I l/ I jl I // I /I /___ // I / / / I I W N 1/ CC I 3 / II I I I Y / / Q 0 /I / /I / 1/ / /' / I /' 1 / I 1 I I 2 I / I / I EX.OVERHEAD / /' // I / 1 I 1 �w�lI�� // I i /I UTILITIES / i /" /// 1/ 1 / I I I I V / 1 / 1 I 1 I I / I/I 1 i I I I Z z / I I / / 1 11 I I D ,/ / / \ 1 I / / 1 1 / I I Q LLJ > o / _� / I 11 1 I // /' 11 /I l I l/ / -- I / / I 1 / I I j 0 C 3 a / II / I 1 I- F 0i \ / I I I / / I1 z I �� 1/ Ili / / 1 / / / / 1 1 IS' o I/ u/ I < x z 0 // / EXJR/A SM H0• /1 1� II/l �� I // I I[p� I I I 0 0 O U / Lc) LLI / INV.IN=858.85' I 1� I/ / I �0p'1 / I ■ I I w u / // INV.OUT=858.75' I I 111ELEPHONE 1 / / I 1 11 j // I 1// BOX I / / / I W / // // / I III 1s.00 // II I I 1 z / / OWW OHW OHW I 9V' J SIDE / / LICLj / I I qY/ARE I STREET / I I E /// \ /1 / I SETBACK / / a 8 /// T / I I I -- ___------- I I\/ I S \ \INV OUT 862C3 _ E :-:t --- PROJECT NO.: 23024 ' - -1DRAWN BY: JAC 1 \ __- Naw-fs� CHECKED BY: JAC DATE: 09/08/23SCALE: • 20 10 0 20 GSTWI GRAVEL DRIVEWAY / \ / I SCALE:1 INCH=20FEET EX-1 LEXINGTON AVE. �'/ l of l / i I \ II I I --� V LEGEND I i A // I I I I AV A EXISTING PROPERTY LINE \ / / I I 1 I \ \ I EXISTING ABUTTING PROPERTY LINE 1 7 1 J N i V A I I I r-- -- V A EXISTING RIGHT-OF-WAY 'L 1�11 / / AV I 1 I I 1 AV A A OHW OH EXISTING OVERHEAD POWER LINE =o / /I , / 1 1 I I 1 I 1 \\\yI EXISTING ABUTTING PROPERTY LINE U 2 M M �S7�38' E�O� 1/ ) I I L ° d IIIVII EXISTING BUILDING SETBACK LINE / / I / --I-_ I �( I I 1 \`{\ \ EXISTING PARKING SETBACK LINE N o z°? l p - - I / / I II I I\�\\ EXISTING EDGE OF PAVEMENT o,a / l I I / I / ' I / /I l I I A\ V v PROPOSED EDGE OF PAVEMENT •/ / i I 1 / I I �� /' / 1 1 _ A\\V PROPOSED ASPHALT PARKING -� % - I / I I �h I 2 / % r / / ,_� • 1J I 1\' II 1 1 / J/ / I \• ��\ PROPOSED CONCRETE O I I DRAINAGE AREA 2 goo PROPOSED CONTOUR MAJOR POST-DEVELOPMENT DRAINAGE BYPASS: PROPOSED CONTOUR MINOR / / J 1 ' \ PROPOSED STORMDRAINAGE I / I \ BYPASS AREA= 14,356SF (0.33AC) ` I•'�,•' I A A iyiiiii PROPOSED DROP INLET a•SH O"•.,� i 1 IMPERVIOUS SURFACE AREA = 3,400SF (0.078AC) 4\.• pe/,,,,, !�Ii■ C=0.49 ® :z�; p ,9 ' // I -• / I , : 3 7 PROPOSED FLARED END SECTION '-L �t� • SH �� I ■ /0- I E \ PERCENTAGE 23.6% Le) tiGF�„E�QF7 I �/ I�� I r V A \'L) \ ..V �� I I I `•.qq.ARV•,. . I \ rep' / �g 1 7 i i I I // 90 /1�14N�.4° • a � I I I ISSUED FOR II . 6� PROPOSED DUMP TE}2 h '/ I ' \! • \' AND ENCLOSUREI I I Drainage Area Drainage Area 1(SF) Drainage Area 2(SF) CONSTRUCTION i ' / •�� \ \I •'• 1III I Total Drainage Area 45,681 14,356 I ` I 1 ��' / �� I II I I On-Site Drainage Area 45,681 14,356 I i 11 1 I /' 1 .111 NM am 1v>. "�� 1 I Off-Site Drainage Area 0 0 r 1 /_ / ' 1 i j II Proposed Impervious Area 31,850 3,400M 1 ' —_2'X60' ,y /N \ ITOw=as5.00l %ImperviousArea 69.7% 23.7%IBOC862.00 I, 1' II I Impervious**Surface Area Drainage Area 1(SF) Drainage Area 2(SF) II 11 I I Buildings 10,000 O a l* 1 I ® PROPOSED I Streets 19,050 3,400 / / ETAI ING WALL I ' I /' , I I Parking 0 0 I 1/1 I�� 1 1 1 ,� I / I if ,' Exist Sidewalks 2,800 DRAINAGE AREA 1 i IBOC 86300 Iml - . TotalingBUA 31,850 3,400 z 42 ' 1 '■' POST-DEVELOPMENT DRAINAGE AREA: 2 z W Z t-----------EX EOP I I =.'F OPOS D 5'SIDFWALK a O 2 W �� I I I� MAIN POOL STORAGE TABLE H 2 2 I DRAINAGE AREA=45,681SF(1.05 AC) • I I o `� Stage SURFACE AREA(SF) Volume(CF) a_ 0 2 /' il� IMPERVIOUS SURFACE AREA= 31,850SF (0.73AC) wil �, m 857 544 0 w -1 W I 1 / taw C=0.77 I i a sss 874 709 0 0 S I I/ I /r I- I I I 1 X 859 1,268 1,071 z z - ''� i 'I _I - / .' i. 1 , I I I W 860 1,719 1,494 I I �,' ' i I I - Ii' II I ., I -' 861 2,226 1,973 '�II / ��i /' i I / I I 862 2,790 2,508 A / I' I I Total 7,755 a 1 i 111111 I 0 _ / I ® � I I II 1 FOREBAYSTORAGETABLE 11 0//PROPOSED24"SPILL ' ' I / I � I Stage SURFACE AREA Volume ICC II/ CURB AND GUTTER i I / ' I , / a - II - - - W N l I�� 11 I 1 I l 860 272 0 1 ,_0, / ' I I 861 502 797 d IL I 1 ' i� _ / I I I 862 788 917 Q // i Total 1,714 I / i IILLJ //1 ' * l� / 1 ll i'/ i'/ I I I TEMPORARY POOL STORAGE TABLE ('� /' I / _ /ii / I / , I 1 1 I Stage SURFACE AREA(SF) Volume(CF) Q / I / / I ,,� ...... I I 862 3,578 - Z w z / //I / / I� / ` �, ' I 76 ' I I I I 863 5,250 2,690 W Y JO // i / I / I I 864 6,229 5,732 0 r2 / 1 I I , I // / I 1 / I I I Total 8,422 I— I- 0 M 1// , / I 1 / • I / I / / II I I Z I Ili n O /' 6 ass I • I, I J 0 z /' 1 �� %I i i l l p O ° o 4 / , li *4 Y : • ; I I > .� .. • I 1 w r fil/ r 5 � . ) E v 4) \ � I ��l �0 I I (n s //'/ \ 8sa I II /11 �1 , S.T., • I /I d 1Ir �y „ i yy / I I NOTES T \ \ � �. 1 � -W� i.=.c.•_ / PROJECT NO.: 23024 „a \\ \ 1 1 ��.5 �� , A �� -yViA• <i"�' I 1. BOUNDARY,TOPOGRAPHY,AND EXISTING CONDITIONS SURVEY o i \\ 1 I \ \\ -� .'• a / " PROVIDED BY STEWART-PROCTOR ON 07-11-2023. DRAWN BY: JAC m i 1 \\ \\ \ / ___H_ - �-H I MO \ 2.THE PROPERTY IS LOCATED IN ZONE X(AREA DETERMINED TO BE CHECKED BY: JAC \ - \ I OUTSIDE THE 0.2%ANNUAL CHANCE AND FUTURE 1%ANNUAL CHANCE o \\ / 1\ \ \ — FLOODPLAIN)BASED ON THE FEMA MAP NUMBER 3710672800J DATED DATE: 09/08/23 7 \i > \ MARCH 16,2009. /' / - \ \\ / /-- \\ SCALE: 1"=20' / - / • / - - , --- \ \ / I 20 10 0 20 3. NO ONSITE STREAMS OR WETLANDS HAVE BEEN IDENTIFIED WITHIN THE $ / / / \ \ - \ / SCALE 1 INCH=20 FEET GSTWI PROJECT OR PARCEL AS SHOWN. / / -\ GRAVEL DRIVEWAY / EX-1 i' / ,/ \\ ___ - I I 4.THIS DRAWING IS NOT FOR RECORDATION. /' /' / \ LEXINGTON AVE. / 1 of 1