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HomeMy WebLinkAboutApplicant's reponse comments 6-5-2025 June 5, 2025 Meredith Badalucca, Assistant Planner Stacy Radford, Zoning & Wetlands Officer Town of Montville Department of Land Use & Development 310 Norwich-New London Turnpike Uncasville, CT 06382 RE: Land Use Application -25SUB3 (001-007-00A) Silver Falls Road Montville, CT CLA-7885 Meredith/Stacy, Attached are responses to all comments received for the above referenced project. Please contact me with any questions. ENGINEERING COMMENTS – Letter dated 5-11-25 Erosion and Sedimentation Control Bond Estimate • Please coordinate the area of seeding with the proposed area of disturbance. Revised • Please include a line item for spreading stockpiled topsoil over the proposed areas of disturbance. Included Stormwater Modeling • Please correct the 10-year, 24-hour rainfall total presented in the Table on page 132 of the revised report. It should be 5.14 inches instead of 4.15 inches. Corrected – see attached revised sheet • Please evaluate the contributing watersheds of the proposed 15-inch culverts located at approximately STA 1+00 and approximately STA 2+30 to demonstrate that they are sized for the appropriate design storm and evaluate the 100-year discharge velocities to ensure that the appropriately sized riprap is specified. These two culverts do not appear to be included in the updated Drainage Report. Culvert and rip-rap at STA 2+30 were evaluated and found to be adequate as it receives limited watershed flow– see attached. Culvert at STA 1+00 was installed to provide wetland conductivity with insignificant watershed flow. Resubdivision Plans • Please include the statement regarding the proposed grading within the limits of the flood plain on Sheet 3. CLA Engineers, Inc. Civil Structural Survey 317 MAIN STREET NORWICH, CT 06360 (860) 886-1966 (860) 886-9165 FAX Statement added to plan • Please provide construction details for the sediment forebay and stone check dam. Provided • Please provide details for the proposed grassed lined swales and riprap swales. Provided OTHER: Planner Comments: Drafting comments addressed on sheet 4 Soil Scientist Comments: This section is in response to a comment letter from Ian Cole CSS dated May 24, 2025 • Note that CLA does not claim that the shrub plantings are to offset the permanent filling of 4950 S.F. of inland wetlands. Mr. Cole requests larger shrubs and additional details regarding the location and monitoring of the plantings. These have been provided on the project plans. The shrubs will be 3-4 feet tall and planted in the native wetland soil at locations chosen by the soil scientist. They will be monitored for 2 years with 100% replacement of any shrubs that die. • CLA is aware that should additional work proceed in Waterford, additional permits on the municipal, state and federal level will be required. The plans properly present the portion of the work regulated by Montville. At this time, it is uncertain if the additional work outside of Waterford will proceed, however if it does it will be presented to the regulatory authorities as a full and complete project. Please contact us with any questions. Sincerely, Robert A. DeLuca, P.E. c: D. Gjergjaj Prepared by CLA Engineers, Inc.Revised 6/5/2025 Item Qty Unit Unit Price Estimate 1 Construction Entrance 1 L.S.$2,500.00 $2,500.00 2 WQV Basin #1 1 L.S.$5,000.00 $5,000.00 3 E&S: Silt Fence Installation & Maintenance 3100 L.F.$2.50 $7,750.00 4 E&S: DBL Silt Fence Installation & Maintenance 450 L.F.$5.00 $2,250.00 5 Install Seed Mix over Disturbed Areas 23,950 S.Y.$0.35 $8,382.50 6 Topsoil over disurbed area 1 L.S.$5,000.00 $5,000.00 $30,882.50 EROSION & SEDIMENTATION CONTROL - BOND ESTIMATE Silver Falls Road Subdivision, Montville CT Total : Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 05 / 14 / 2025 Hyd. No. 1 Existing Watershed #1 Hydrograph type = SCS Runoff Peak discharge = 53.72 cfs Storm frequency = 10 yrs Time to peak = 756 min Time interval = 6 min Hyd. volume = 479,613 cuft Drainage area = 129.000 ac Curve number = 55* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 46.90 min Total precip. = 5.14 in Distribution = Custom Storm duration = M:\NOAA Type D Distribution.cdsShape factor = 484 * Composite (Area/CN) = [(129.000 x 55)] / 129.000 1 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 10.00 10.00 20.00 20.00 30.00 30.00 40.00 40.00 50.00 50.00 60.00 60.00 Q (cfs) Time (min) Existing Watershed #1 Hyd. No. 1 -- 10 Year Hyd No. 1 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 05 / 14 / 2025 Hyd. No. 2 Existing watershed #2 Hydrograph type = SCS Runoff Peak discharge = 81.68 cfs Storm frequency = 10 yrs Time to peak = 786 min Time interval = 6 min Hyd. volume = 964,695 cuft Drainage area = 257.000 ac Curve number = 55 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 76.40 min Total precip. = 5.14 in Distribution = Custom Storm duration = M:\NOAA Type D Distribution.cdsShape factor = 484 2 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 10.00 10.00 20.00 20.00 30.00 30.00 40.00 40.00 50.00 50.00 60.00 60.00 70.00 70.00 80.00 80.00 90.00 90.00 Q (cfs) Time (min) Existing watershed #2 Hyd. No. 2 -- 10 Year Hyd No. 2 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 05 / 14 / 2025 Hyd. No. 3 Proposed Watershed #1 Hydrograph type = SCS Runoff Peak discharge = 53.72 cfs Storm frequency = 10 yrs Time to peak = 756 min Time interval = 6 min Hyd. volume = 479,613 cuft Drainage area = 129.000 ac Curve number = 55* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 46.90 min Total precip. = 5.14 in Distribution = Custom Storm duration = M:\NOAA Type D Distribution.cdsShape factor = 484 * Composite (Area/CN) = [(1.000 x 98) + (2.400 x 61) + (125.600 x 55)] / 129.000 3 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 10.00 10.00 20.00 20.00 30.00 30.00 40.00 40.00 50.00 50.00 60.00 60.00 Q (cfs) Time (min) Proposed Watershed #1 Hyd. No. 3 -- 10 Year Hyd No. 3 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 05 / 14 / 2025 Hyd. No. 4 Proposed Watershed #2 Hydrograph type = SCS Runoff Peak discharge = 81.68 cfs Storm frequency = 10 yrs Time to peak = 786 min Time interval = 6 min Hyd. volume = 964,695 cuft Drainage area = 257.000 ac Curve number = 55* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 76.40 min Total precip. = 5.14 in Distribution = Custom Storm duration = M:\NOAA Type D Distribution.cdsShape factor = 484 * Composite (Area/CN) = [(0.850 x 61) + (1.000 x 98) + (255.150 x 55)] / 257.000 4 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 10.00 10.00 20.00 20.00 30.00 30.00 40.00 40.00 50.00 50.00 60.00 60.00 70.00 70.00 80.00 80.00 90.00 90.00 Q (cfs) Time (min) Proposed Watershed #2 Hyd. No. 4 -- 10 Year Hyd No. 4 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 05 / 14 / 2025 Hyd. No. 6 Common Drive North Side Swale Hydrograph type = SCS Runoff Peak discharge = 0.764 cfs Storm frequency = 10 yrs Time to peak = 732 min Time interval = 6 min Hyd. volume = 3,248 cuft Drainage area = 0.360 ac Curve number = 76* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 17.80 min Total precip. = 5.14 in Distribution = Custom Storm duration = M:\NOAA Type D Distribution.cdsShape factor = 484 * Composite (Area/CN) = [(0.180 x 98) + (0.180 x 54)] / 0.360 5 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 0.10 0.10 0.20 0.20 0.30 0.30 0.40 0.40 0.50 0.50 0.60 0.60 0.70 0.70 0.80 0.80 0.90 0.90 1.00 1.00 Q (cfs) Time (min) Common Drive North Side Swale Hyd. No. 6 -- 10 Year Hyd No. 6 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 05 / 14 / 2025 Hyd. No. 7 Common Drive South Side Swale Hydrograph type = SCS Runoff Peak discharge = 0.251 cfs Storm frequency = 10 yrs Time to peak = 750 min Time interval = 6 min Hyd. volume = 2,218 cuft Drainage area = 0.880 ac Curve number = 49* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 21.90 min Total precip. = 5.14 in Distribution = Custom Storm duration = M:\NOAA Type D Distribution.cdsShape factor = 484 * Composite (Area/CN) = [(0.170 x 98) + (0.123 x 54) + (0.590 x 34)] / 0.880 6 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 0.05 0.05 0.10 0.10 0.15 0.15 0.20 0.20 0.25 0.25 0.30 0.30 0.35 0.35 0.40 0.40 0.45 0.45 0.50 0.50 Q (cfs) Time (min) Common Drive South Side Swale Hyd. No. 7 -- 10 Year Hyd No. 7 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 05 / 14 / 2025 Hyd. No. 8 To WQV Basin 2 Hydrograph type = SCS Runoff Peak discharge = 0.433 cfs Storm frequency = 10 yrs Time to peak = 750 min Time interval = 6 min Hyd. volume = 4,343 cuft Drainage area = 2.040 ac Curve number = 47* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 21.70 min Total precip. = 5.14 in Distribution = Custom Storm duration = M:\NOAA Type D Distribution.cdsShape factor = 484 * Composite (Area/CN) = [(0.240 x 98) + (0.530 x 54) + (1.270 x 34)] / 2.040 7 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 0.05 0.05 0.10 0.10 0.15 0.15 0.20 0.20 0.25 0.25 0.30 0.30 0.35 0.35 0.40 0.40 0.45 0.45 0.50 0.50 Q (cfs) Time (min) To WQV Basin 2 Hyd. No. 8 -- 10 Year Hyd No. 8 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 05 / 14 / 2025 Hyd. No. 9 WQV2 OUTFLOW Hydrograph type = Reservoir Peak discharge = 0.045 cfs Storm frequency = 10 yrs Time to peak = 1014 min Time interval = 6 min Hyd. volume = 828 cuft Inflow hyd. No. = 8 - To WQV Basin 2 Max. Elevation = 187.59 ft Reservoir name = wqv2 Max. Storage = 2,188 cuft Storage Indication method used. Exfiltration extracted from Outflow. 8 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 0.05 0.05 0.10 0.10 0.15 0.15 0.20 0.20 0.25 0.25 0.30 0.30 0.35 0.35 0.40 0.40 0.45 0.45 0.50 0.50 Q (cfs) Time (min) WQV2 OUTFLOW Hyd. No. 9 -- 10 Year Hyd No. 9 Hyd No. 8 Total storage used = 2,188 cuft Pond Report 9 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 05 / 14 / 2025 Pond No. 1 - wqv2 Pond Data Contours -User-defined contour areas. Conic method used for volume calculation. Begining Elevation = 185.00 ft Stage / Storage Table Stage (ft) Elevation (ft) Contour area (sqft) Incr. Storage (cuft) Total storage (cuft) 0.00 185.00 00 0 0 1.00 186.00 900 300 300 2.00 187.00 1,260 1,075 1,375 2.50 187.50 1,420 670 2,044 3.00 188.00 1,680 774 2,818 4.00 189.00 2,160 1,915 4,733 Culvert / Orifice Structures Weir Structures [A] [B] [C] [PrfRsr] [A] [B] [C] [D] Rise (in)= 15.00 Inactive Inactive Inactive Span (in)= 15.00 0.00 0.00 0.00 No. Barrels = 1 0 0 0 Invert El. (ft)= 187.50 0.00 0.00 0.00 Length (ft)= 200.00 0.00 0.00 0.00 Slope (%)= 1.20 0.00 0.00 n/a N-Value = .012 .013 .013 n/a Orifice Coeff.= 0.60 0.60 0.60 0.60 Multi-Stage = n/a No No No Crest Len (ft)Inactive Inactive Inactive Inactive Crest El. (ft)= 187.50 0.00 0.00 0.00 Weir Coeff.= 3.33 3.33 3.33 3.33 Weir Type = 1 --- --- --- Multi-Stage = Yes No No No Exfil.(in/hr)= 1.000 (by Contour) 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 / Storage / Discharge Table Stage Storage Elevation Clv A Clv B Clv C PrfRsr Wr A Wr B Wr C Wr D Exfil User Total ft cuft ft cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs 0.00 0 185.00 0.00 --- --- --- 0.00 --- --- --- 0.000 --- 0.000 0.10 30 185.10 0.00 --- --- --- 0.00 --- --- --- 0.002 --- 0.002 0.20 60 185.20 0.00 --- --- --- 0.00 --- --- --- 0.004 --- 0.004 0.30 90 185.30 0.00 --- --- --- 0.00 --- --- --- 0.006 --- 0.006 0.40 120 185.40 0.00 --- --- --- 0.00 --- --- --- 0.008 --- 0.0080.50 150 185.50 0.00 --- --- --- 0.00 --- --- --- 0.010 --- 0.010 0.60 180 185.60 0.00 --- --- --- 0.00 --- --- --- 0.012 --- 0.012 0.70 210 185.70 0.00 --- --- --- 0.00 --- --- --- 0.015 --- 0.015 0.80 240 185.80 0.00 --- --- --- 0.00 --- --- --- 0.017 --- 0.017 0.90 270 185.90 0.00 --- --- --- 0.00 --- --- --- 0.019 --- 0.0191.00 300 186.00 0.00 --- --- --- 0.00 --- --- --- 0.021 --- 0.021 1.10 407 186.10 0.00 --- --- --- 0.00 --- --- --- 0.022 --- 0.022 1.20 515 186.20 0.00 --- --- --- 0.00 --- --- --- 0.022 --- 0.022 1.30 622 186.30 0.00 --- --- --- 0.00 --- --- --- 0.023 --- 0.023 1.40 730 186.40 0.00 --- --- --- 0.00 --- --- --- 0.024 --- 0.024 1.50 837 186.50 0.00 --- --- --- 0.00 --- --- --- 0.025 --- 0.025 1.60 945 186.60 0.00 --- --- --- 0.00 --- --- --- 0.026 --- 0.026 1.70 1,052 186.70 0.00 --- --- --- 0.00 --- --- --- 0.027 --- 0.027 1.80 1,160 186.80 0.00 --- --- --- 0.00 --- --- --- 0.027 --- 0.027 1.90 1,267 186.90 0.00 --- --- --- 0.00 --- --- --- 0.028 --- 0.028 2.00 1,375 187.00 0.00 --- --- --- 0.00 --- --- --- 0.029 --- 0.029 2.05 1,442 187.05 0.00 --- --- --- 0.00 --- --- --- 0.030 --- 0.030 2.10 1,509 187.10 0.00 --- --- --- 0.00 --- --- --- 0.030 --- 0.030 2.15 1,576 187.15 0.00 --- --- --- 0.00 --- --- --- 0.030 --- 0.030 2.20 1,643 187.20 0.00 --- --- --- 0.00 --- --- --- 0.031 --- 0.031 2.25 1,710 187.25 0.00 --- --- --- 0.00 --- --- --- 0.031 --- 0.0312.30 1,777 187.30 0.00 --- --- --- 0.00 --- --- --- 0.031 --- 0.031 2.35 1,844 187.35 0.00 --- --- --- 0.00 --- --- --- 0.032 --- 0.032 2.40 1,910 187.40 0.00 --- --- --- 0.00 --- --- --- 0.032 --- 0.032 2.45 1,977 187.45 0.00 --- --- --- 0.00 --- --- --- 0.032 --- 0.032 2.50 2,044 187.50 0.00 --- --- --- 0.00 --- --- --- 0.033 --- 0.033 2.55 2,122 187.55 0.01 ic --- --- --- 0.00 --- --- --- 0.033 --- 0.046 2.60 2,199 187.60 0.05 ic --- --- --- 0.00 --- --- --- 0.034 --- 0.084 2.65 2,277 187.65 0.11 ic --- --- --- 0.00 --- --- --- 0.035 --- 0.145 2.70 2,354 187.70 0.19 ic --- --- --- 0.00 --- --- --- 0.035 --- 0.228 2.75 2,431 187.75 0.30 ic --- --- --- 0.00 --- --- --- 0.036 --- 0.3342.80 2,509 187.80 0.42 ic --- --- --- 0.00 --- --- --- 0.036 --- 0.459 Continues on next page... 10 wqv2 Stage / Storage / Discharge Table Stage Storage Elevation Clv A Clv B Clv C PrfRsr Wr A Wr B Wr C Wr D Exfil User Total ft cuft ft cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs 2.85 2,586 187.85 0.57 ic --- --- --- 0.00 --- --- --- 0.037 --- 0.604 2.90 2,664 187.90 0.73 ic --- --- --- 0.00 --- --- --- 0.038 --- 0.768 2.95 2,741 187.95 0.91 ic --- --- --- 0.00 --- --- --- 0.038 --- 0.948 3.00 2,818 188.00 1.10 ic --- --- --- 0.00 --- --- --- 0.039 --- 1.143 3.10 3,010 188.10 1.54 ic --- --- --- 0.00 --- --- --- 0.040 --- 1.577 3.20 3,201 188.20 2.02 ic --- --- --- 0.00 --- --- --- 0.041 --- 2.057 3.30 3,393 188.30 2.53 ic --- --- --- 0.00 --- --- --- 0.042 --- 2.569 3.40 3,584 188.40 3.06 ic --- --- --- 0.00 --- --- --- 0.043 --- 3.102 3.50 3,776 188.50 3.58 ic --- --- --- 0.00 --- --- --- 0.044 --- 3.629 3.60 3,967 188.60 4.09 ic --- --- --- 0.00 --- --- --- 0.046 --- 4.131 3.70 4,159 188.70 4.52 ic --- --- --- 0.00 --- --- --- 0.047 --- 4.563 3.80 4,350 188.80 4.85 ic --- --- --- 0.00 --- --- --- 0.048 --- 4.9023.90 4,542 188.90 5.20 ic --- --- --- 0.00 --- --- --- 0.049 --- 5.250 4.00 4,733 189.00 5.53 ic --- --- --- 0.00 --- --- --- 0.050 --- 5.577 ...End Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 05 / 14 / 2025 Hyd. No. 11 To Future Crossing Hydrograph type = SCS Runoff Peak discharge = 9.875 cfs Storm frequency = 10 yrs Time to peak = 732 min Time interval = 6 min Hyd. volume = 42,144 cuft Drainage area = 5.180 ac Curve number = 73* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 13.90 min Total precip. = 5.14 in Distribution = Custom Storm duration = M:\NOAA Type D Distribution.cdsShape factor = 484 * Composite (Area/CN) = [(3.000 x 98) + (0.550 x 56) + (1.630 x 34)] / 5.180 11 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 2.00 2.00 4.00 4.00 6.00 6.00 8.00 8.00 10.00 10.00 Q (cfs) Time (min) To Future Crossing Hyd. No. 11 -- 10 Year Hyd No. 11 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 05 / 14 / 2025 Hyd. No. 12 Combined to Future Crossing Hydrograph type = Combine Peak discharge = 9.875 cfs Storm frequency = 10 yrs Time to peak = 732 min Time interval = 6 min Hyd. volume = 42,973 cuft Inflow hyds. = 9, 11 Contrib. drain. area = 5.180 ac 12 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 2.00 2.00 4.00 4.00 6.00 6.00 8.00 8.00 10.00 10.00 Q (cfs) Time (min) Combined to Future Crossing Hyd. No. 12 -- 10 Year Hyd No. 12 Hyd No. 9 Hyd No. 11 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 05 / 14 / 2025 Hyd. No. 14 WQB1 Hydrograph type = Reservoir Peak discharge = 9.327 cfs Storm frequency = 10 yrs Time to peak = 732 min Time interval = 6 min Hyd. volume = 33,525 cuft Inflow hyd. No. = 12 - Combined to Future CrossingMax. Elevation = 129.29 ft Reservoir name = WQB1 Max. Storage = 5,576 cuft Storage Indication method used. Exfiltration extracted from Outflow. 13 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Q (cfs) 0.00 0.00 2.00 2.00 4.00 4.00 6.00 6.00 8.00 8.00 10.00 10.00 Q (cfs) Time (min) WQB1 Hyd. No. 14 -- 10 Year Hyd No. 14 Hyd No. 12 Total storage used = 5,576 cuft Pond Report 14 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 05 / 14 / 2025 Pond No. 2 - WQB1 Pond Data Contours -User-defined contour areas. Conic method used for volume calculation. Begining Elevation = 127.50 ft Stage / Storage Table Stage (ft) Elevation (ft) Contour area (sqft) Incr. Storage (cuft) Total storage (cuft) 0.00 127.50 00 0 0 0.50 128.00 3,120 520 520 1.50 129.00 4,460 3,770 4,290 2.50 130.00 5,000 4,727 9,017 Culvert / Orifice Structures Weir Structures [A] [B] [C] [PrfRsr] [A] [B] [C] [D] Rise (in)= 0.00 0.00 0.00 0.00 Span (in)= 0.00 0.00 0.00 0.00 No. Barrels = 0 0 0 0 Invert El. (ft)= 0.00 0.00 0.00 0.00 Length (ft)= 0.00 0.00 0.00 0.00 Slope (%)= 0.00 0.00 0.00 n/a N-Value = .013 .013 .013 n/a Orifice Coeff.= 0.60 0.60 0.60 0.60 Multi-Stage = n/a No No No Crest Len (ft)= 25.00 0.00 0.00 0.00 Crest El. (ft)= 129.00 0.00 0.00 0.00 Weir Coeff.= 2.60 3.33 3.33 3.33 Weir Type = Broad --- --- --- Multi-Stage = No No No No Exfil.(in/hr)= 1.000 (by Contour) 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 / Storage / Discharge Table Stage Storage Elevation Clv A Clv B Clv C PrfRsr Wr A Wr B Wr C Wr D Exfil User Total ft cuft ft cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs 0.00 0 127.50 --- --- --- --- 0.00 --- --- --- 0.000 --- 0.000 0.05 52 127.55 --- --- --- --- 0.00 --- --- --- 0.007 --- 0.0070.10 104 127.60 --- --- --- --- 0.00 --- --- --- 0.014 --- 0.014 0.15 156 127.65 --- --- --- --- 0.00 --- --- --- 0.022 --- 0.022 0.20 208 127.70 --- --- --- --- 0.00 --- --- --- 0.029 --- 0.029 0.25 260 127.75 --- --- --- --- 0.00 --- --- --- 0.036 --- 0.036 0.30 312 127.80 --- --- --- --- 0.00 --- --- --- 0.043 --- 0.0430.35 364 127.85 --- --- --- --- 0.00 --- --- --- 0.051 --- 0.051 0.40 416 127.90 --- --- --- --- 0.00 --- --- --- 0.058 --- 0.058 0.45 468 127.95 --- --- --- --- 0.00 --- --- --- 0.065 --- 0.065 0.50 520 128.00 --- --- --- --- 0.00 --- --- --- 0.072 --- 0.072 0.60 897 128.10 --- --- --- --- 0.00 --- --- --- 0.075 --- 0.0750.70 1,274 128.20 --- --- --- --- 0.00 --- --- --- 0.078 --- 0.078 0.80 1,651 128.30 --- --- --- --- 0.00 --- --- --- 0.082 --- 0.082 0.90 2,028 128.40 --- --- --- --- 0.00 --- --- --- 0.085 --- 0.085 1.00 2,405 128.50 --- --- --- --- 0.00 --- --- --- 0.088 --- 0.088 1.10 2,782 128.60 --- --- --- --- 0.00 --- --- --- 0.091 --- 0.091 1.20 3,159 128.70 --- --- --- --- 0.00 --- --- --- 0.094 --- 0.094 1.30 3,536 128.80 --- --- --- --- 0.00 --- --- --- 0.097 --- 0.097 1.40 3,913 128.90 --- --- --- --- 0.00 --- --- --- 0.100 --- 0.100 1.50 4,290 129.00 --- --- --- --- 0.00 --- --- --- 0.103 --- 0.103 1.60 4,762 129.10 --- --- --- --- 2.06 --- --- --- 0.104 --- 2.160 1.70 5,235 129.20 --- --- --- --- 5.81 --- --- --- 0.106 --- 5.920 1.80 5,708 129.30 --- --- --- --- 10.68 --- --- --- 0.107 --- 10.79 1.90 6,180 129.40 --- --- --- --- 16.45 --- --- --- 0.108 --- 16.55 2.00 6,653 129.50 --- --- --- --- 22.98 --- --- --- 0.109 --- 23.09 2.10 7,126 129.60 --- --- --- --- 30.21 --- --- --- 0.111 --- 30.32 2.20 7,599 129.70 --- --- --- --- 38.07 --- --- --- 0.112 --- 38.182.30 8,071 129.80 --- --- --- --- 46.51 --- --- --- 0.113 --- 46.63 2.40 8,544 129.90 --- --- --- --- 55.50 --- --- --- 0.114 --- 55.62 2.50 9,017 130.00 --- --- --- --- 65.00 --- --- --- 0.116 --- 65.12 Hydraflow Rainfall Report 15 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 05 / 14 / 2025 Return Intensity-Duration-Frequency Equation Coefficients (FHA) Period (Yrs)B D E (N/A) 1 18.1733 3.5000 0.7010 -------- 2 22.7904 3.9000 0.7142 -------- 3 0.0000 0.0000 0.0000 -------- 5 26.8118 3.1000 0.7005 -------- 10 32.8535 3.8000 0.7098 -------- 25 38.4672 3.6000 0.7049 -------- 50 43.8334 3.7000 0.7074 -------- 100 48.6510 3.7000 0.7060 -------- File name: Brooklyn 2024.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 4.05 2.93 2.35 1.99 1.74 1.55 1.41 1.29 1.20 1.12 1.05 0.99 2 4.78 3.48 2.79 2.36 2.06 1.84 1.67 1.53 1.42 1.32 1.24 1.17 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 6.19 4.42 3.53 2.97 2.59 2.31 2.09 1.92 1.78 1.66 1.56 1.47 10 7.02 5.10 4.09 3.46 3.02 2.70 2.45 2.25 2.08 1.94 1.82 1.72 25 8.44 6.11 4.90 4.14 3.62 3.23 2.93 2.69 2.49 2.32 2.18 2.06 50 9.49 6.88 5.52 4.67 4.08 3.64 3.30 3.03 2.81 2.62 2.46 2.32 100 10.56 7.67 6.15 5.21 4.55 4.06 3.68 3.38 3.13 2.92 2.74 2.59 Tc = time in minutes. Values may exceed 60. Rainfall Precipitation Table (in) Precip. file name: M:\7000\7300\7386 Reynolds St. Improvements\Studies-Calculations\Danielson storms.pcp Storm Distribution 1-yr 2-yr 3-yr 5-yr 10-yr 25-yr 50-yr 100-yr SCS 24-hour 2.89 3.45 0.00 4.37 5.14 6.19 6.98 7.82 SCS 6-Hr 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Huff-1st 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 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 2.89 3.45 0.00 4.37 5.14 6.19 6.98 7.82 Culvert Report Hydraflow Express Extension for Autodesk® AutoCAD® Civil 3D® by Autodesk, Inc. Wednesday, May 14 2025 2+30 Crossing Invert Elev Dn (ft) = 130.50 Pipe Length (ft) = 35.00 Slope (%) = 2.86 Invert Elev Up (ft) = 131.50 Rise (in) = 15.0 Shape = Circular Span (in) = 15.0 No. Barrels = 1 n-Value = 0.012 Culvert Type = Circular Concrete Culvert Entrance = Square edge w/headwall (C) Coeff. K,M,c,Y,k = 0.0098, 2, 0.0398, 0.67, 0.5 Embankment Top Elevation (ft) = 134.00 Top Width (ft) = 24.00 Crest Width (ft) = 40.00 Calculations Qmin (cfs) = 1.43 Qmax (cfs) = 1.43 Tailwater Elev (ft) = (dc+D)/2 Highlighted Qtotal (cfs) = 1.43 Qpipe (cfs) = 1.43 Qovertop (cfs) = 0.00 Veloc Dn (ft/s) = 1.59 Veloc Up (ft/s) = 3.36 HGL Dn (ft) = 131.36 HGL Up (ft) = 131.97 Hw Elev (ft) = 132.14 Hw/D (ft) = 0.52 Flow Regime = Inlet Control