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Home My WebLink AboutSW4240102_Stormwater Narrative_20240823 STORMWATER NARRATIVE AND DESIGN CALCULATIONS For: PINE RIDGE- PHASE 2 Rural Hall, North Carolina ADI Project No. 23-011 .,00111111// Developer: ,. CAR O = .OF i LR Pine Ridge Associates,LLC / 9.: 4905 Dickens Road, Suite 201 AL Richmond,Viriginia 23230 . kl 197 'Q 1 p1 o Prepared by: ST •••I.N. M.CP ��1!!11l ItSt�4 Allied Design,Inc. 4720 Kester Mill Road Winston-Salem,NC 27103 (336) 765-2377 scausey@allied-engsurv.com A STORMWATER NARRATIVE DAVIDSON CHARTER ACADEMY TABLE OF CONTENTS A. Introduction B. Methodology C. Site Design and Assessment D. Conclusion Appendix A. NOAA Rainfall Data (Hydraflow Rainfall Report) B. Curve Number Summary C. Wet Pond Calculations D. 1-Year/24 Hour Frequency Design Storm Hydrographs E. 100-Year Frequency Design Storm Hydrographs F. Pond Report G. Outlet Stabilization Calculations H. Ditch Calculations I. USDA Soils Report Allied Design Inc. Project No.: 23-011 Page 1 STORMWATER NARRATIVE DAVIDSON CHARTER ACADEMY A. Introduction The Pine Ridge Subdivision is a proposed 23-acre residential development located off Ketner Farm Road in Rural Hall, North Carolina. The proposed development consists of 63 single family lots with 11 acres of impervious built upon area (bua) In accordance with the requirements of NCDEQ Post Construction Stormwater program, the project will require a stormwater management permit. Stormwater management permit approval will require design and construction of permanent water quality measure to manage the runoff from all new impervious coverage. The stormwater management plan for Pine Ridge utilizes a wet detention basin as the primary Stormwater Control Measures (SCM) to meet NCDEQ's post construction stormwater management requirements. The wet detention basin will be designed to treat the first 1-inch of runoff for quality treatment. B. Methodology Reference for preparation of the stormwater management plan is made to the North Carolina Division of Environmental Quality's "New Stormwater Design Manual" (MDC's). City/County topographical maps, site surveys, and the proposed site development plans were utilized to delineate the post-development runoff patterns. The USDA Soils Survey was referenced and used to determine the Runoff Curve Numbers (CN's). The storm events modeled in this design are based on the SCS 24 Hour Storm Distribution for the 1-year storm and the 6 Hour Storm Distribution for 100-year design storm. The Intensity-Duration Frequency Curves were established using the FHA Method. Precipitation frequency estimates were obtained from NOAA. Inflow hydrographs were derived from the SCS Unit Hydrograph Method and routed through the proposed wet detention basin. The Storage Indication Method is used to Allied Design Inc. Project No.: 23-011 Page 2 STORMWATER NARRATIVE DAVIDSON CHARTER ACADEMY determine and verify design of the primary outlet structure. "Hydraflow Hydrographs", 2004 edition software was used to perform the routing calculations. The wet detention basin design is based on capture of the first 1-inch of runoff. The required surface area and volume is calculated based on the SA/DA method. Design of forebays is included and are sized to provide 15-20% of the volume of the wet detention basin. The wet detention basin will utilize a precast concrete outlet structure to control the post-developed runoff rates from the 1-year, 24-Hour storm event to a runoff rate that minimizes hydrologic impacts to the receiving stream. The outlet structure is modeled to assume 50% blockage of the overflow weir. The proposed detention is designed to ensure the maximum storage elevation during the 100-year storm remains at least 1 foot below the top of dam elevation. C. Conclusion This Stormwater Narrative concludes that the project is being developed in accordance with the Wet Pond provisions of the MDC. As indicated by the stormwater management plans and calculations included in this report, stormwater quality and is being provided on-site in accordance with NCDEQ's stormwater management requirements. 1. Stormwater Quality Management The drainage area routed to the wet detention basin includes 31.45 acres with approximately 11.64 acres being impervious. It should be noted that approximately 0.64 acres of the impervious area is offsite and will be managed by the SCM. The wet detention basin captures the first 1-inch of runoff from the post- developed drainage areas and treats the flow in accordance with the requirements of the NCDEQ's Stormwater Design Manual. The routing hydrographs included in this report also verify that the post-developed runoff for the 1-yr 24-hr water quality event Page 3 Allied Design Inc. Project No.: 23-011 STORMWATER NARRATIVE DAVIDSON CHARTER ACADEMY to a runoff rate that minimizes hydrologic impacts to the receiving stream. A summary of the water quality management is provided as follows: Summary of Water Quality Management Management Aspects Pond 1 Required Provided Water Quality Volume (cf) 36,761 39,109 Water Quality Elevation (ft) 908.96 909.00 Main Pool Surface Area (sf) 13,012 13,438 Allied Design Inc. Project No.: 23-011 Page 4 STORMWATER NARRATIVE DAVIDSON CHARTER ACADEMY Appendix Allied Design Inc. Project No.: 23-011 Page 5 A . NO PA Atlas 14,Volume 2,Version 3 '`"`°` ' Location name: Rural Hall, North Carolina, USA* "�' g • Latitude: 36.2314°, Longitude: -80.3111° norm Elevation:988 ft** SNTES ' *source:ESRI M Ts \,, s` **source:USG S """` PO NT PRECIPITATIO NFREQ LENCY ESTIMATES G M.Bonnin,D.Matin,B.Lin,T.Parzybok,M Yekta,and D.Riley NO A4,National Weather Service,Silver Spring,M ayland PF tabular I PF graphical I its & aerials PF tabular PDS-based point precipitation frequency estimates w kh 90% confidence intervals (in inches/hour)1 Average recurrence interval(years) Duration I - - 1251 02 55 01 002 005 001 000 5-m it 4.44 5.28 6.23 6.89 7.68 8.22 8.72 9.17 9.71 I 10.1 (4.09-4.81) (4.88-5.76) (5.75-6.78) (6.35-7.49) (7.03-8.35) (7.48-8.95) (7.87-9.50) (8.22-10.0) (8.58-10.7) (8.83-11.1) 10-m in 3.55 4.22 4.99 5.51 6.12 6.55 6.93 7.27 7.67 7.94 (3.27-3.85) (3.90-4.60) (4.60-5.43) (5.08-5.99) (5.60-6.65) (5.95-7.12) (6.26-7.55) (6.52-7.95) (6.79-8.43) I (6.95-8.76) 15-m in 2.95 3.54 4.21 4.65 5.17 5.52 5.84 6.12 6.44 6.64 (2.73-3.20) (3.27-3.86) (3.88-4.58) (4.28-5.05) (4.73-5.62)_ (5.02-6.01) (5.27-6.36) I(5.48-6.68) (5.70-7.08) (5.82-7.33) 30-m in2.02 2.44 2.99 3.37 3.83 4.16 4.47 4.76 5.12 5.38 (1.87-2.20) (2.26-2.66) (2.75-3.25) (3.10-3.66) (3.50-4.16) (3.78-4.53) (4.04-4.87) (4.27-5.20)_ (4.53-5.63) (4.71-5.93) 60-m in 1.26 1.53 1.92 2.19 2.55 2.82 3.08 3.34 3.68 3.92 (1.16-1.37) (1.42-1.67) (1.77-2.09) (2.02-2.38) (2.33-2.77) (2.56-3.07) (2.78-3.36) (2.99-3.65) (3.25-4.04) (3.44-4.33) 2-hr 0.748 0.911 1.15 1.32 1.56 1.75 1.93 2.12 2.38 2.57 (0.688-0.817) (0.837-0.995) (1.05-1.25) (1.21-1.44) (1.42-1.70) (1.58-1.91) (1.73-2.12) (1.88-2.33) (2.08-2.62) (2.22-2.85) 3-hr 0.537 0.655 0.824 0.954 1.13 1.26 1.40 1.54 1.73 1.88 (0.494-0.587) (0.603-0.716) (0.758-0.900) (0.873-1.04) (1.02-1.23) (1.14-1.38) (1.25-1.53) (1.36-1.68) (1.51-1.90) (1.62-2.07) 6-hr 0.332 0.402 0.506 0.588 0.700 0.790 0.883 0.979 1.11 1.22 (0.305-0.362) (0.371-0.441) (0.465-0.554) (0.538-0.642) (0.635-0.764) (0.711-0.861) (0.788-0.962) (0.863-1.07) (0.965-1.22) (1.04-1.34) 12-hr 0.199 0.242 0.305 0.356 0.428 0.486 0.548 0.613 0.707 0.783 (0.183-0.218) (0.222-0.264) (0.280-0.333) (0.325-0.387) (0.387-0.464) (0.437-0.526) (0.488-0.593) (0.538-0.664) (0.609-0.767) (0.663-0.851) 24-hr 0.120 0.145 0.183 0.214 0.257 0.293 0.331 0.371 0.428 I 0.476 (0.111-0.130) (0.134-0.157) (0.169-0.198) (0.197-0.231) (0.236-0.278) (0.267-0.316) (0.300-0.357) (0.334-0.401) (0.382-0.463) (0.421-0.515) 2-day 0.070 0.085 0.106 0.123 0.147 0.166 0.185 ' 0.206 0.236 0.259 (0.065-0.075) (0.079-0.091) (0.098-0.114) (0.114-0.132) (0.135-0.158) (0 152-0.178) (0.170-0.200) (0.188-0.223) (0.212-0.255) (0.232-0.281) 3-day 0.049 0.060 0.075 0.086 0.103 0.116 0.130 0.145 0.165 0.182 (0.046-0.053) (0.055-0.064) (0.069-0.080) (0.080-0.093) (0.095-0.110) (0.107-0.125) (0.119-0.140) (0.132-0.156) (0.149-0.179) (0.163-0.197)I 4-day 0.039 0.047 0.059 0.068 0.081 0.091 0.102 0.114 0.130 0.143 (0.036-0.042) (0.044-0.050) (0.055-0.063) (0.063-0.073) (0.075-0.087) (0.084-0.098) (0.094-0.110) (0.104-0.122) (0.118-0.140) (0.128-0.155) 7-day 0.025 0.030 0.037 0.043 0.051 0.057 0.063 0.070 0.079 0.087 (0.024-0.027) (0.028-0.032) (0.035-0.040) (0.040-0.046) (0.047-0.054) (0.052-0.061) (0.058-0.068) (0.064-0.075) (0.072-0.085) (0.078-0.094) 10-day 0.020 0.024 0.029 0.033 0.039 0.044 0.048 0.053 0.060 0.065 (0.019-0.021) (0.023-0.026) (0.027-0.031) (0.031-0.035) (0.036-0.041) (0.040-0.046) (0.045-0.051) (0.049-0.057) (0.054-0.064) (0.059-0.070) 20-day 0.013 0.016 0.019 0.022 0.025 0.028 I 0.030 0.033 0.037 I 0.039 (0.013-0.014) (0.015-0.017) (0.018-0.020) (0.020-0.023) (0.023-0.026) (0.026-0.029)1(0.028-0.032) (0.031-0.035) (0.034-0.039)1(0.036-0.042)i 30-day 0.011 0.013 0.015 0.017 0.019 0.021 0.023 0.024 0.026 0.028 (0.010-0.011) (0.012-0.014) (0.014-0.016) (0.016-0.018) (0.018-0.020) (0.020-0.022) (0.021-0.024) (0.023-0.026) (0.025-0.028) (0.026-0.030) 45-day 0.009 0.011 0.012 0.014 0.015 0.017 0.018 0.019 0.021 0.022 (0.009-0.010) (0.010-0.011) (0.012-0.013)_(0.013-0.014) (0.015-0.016) (0.016-0.018) (0.017-0.019) (0.018-0.020) (0.019-0.022) (0.020-0.023) 60-day 0.008 0.010 0.011 0.012 0.013 0.014 0.015 0.016 0.017 0.018 (0.008-0.008) (0.009-0.010) (0.010-0.011) (0.011-0.013) (0.013-0.014) (0.014-0.015) (0.014-0.016) (0.015-0.017) (0.016-0.018) (0.017-0.019) 1 Precipitation frequency(PF)estimates in this table are based on frequency analysis of partial duration series(PDS). Num hers in parenthesis are PF estimates at lower and upper bounds of the 90%confidence interval.The probability that precipitation frequency estimates(for a given duration and average recurrence interval)will be greater than the upper bound(or less than the lower bound)is 5%.Estimates at upper bounds are not checked against probable maxim t n precipitation(PM P)estimates and m ay be higher than currently valid PM Pvalues. Please refer to NO AA Atlas 14 docum ait form are inform ation. Back to Top PF graphical NO AA Atlas 14,Volume 2,Version 3 '`, • Location name: Rural Hall, North Carolina, USA* t ";'\ g Latitude: 36.2314°, Longitude: -80.3111° nonli Elevation:988 ft** 11111 ) S ' *source:ESRI Maps \,,, s` **source:USG S """` PO NT PRECIPITATIO NFREQ LENCY ESTIMATES G M.Bonnin,D.Matin,B.Lin,T.Parzybok,M Yekta,and D.Riley NO PA,National Weather Service,Silver Spring,M ayland PF tabular I PF graphical I M 4)s & aerials PF tabular PDS-based point precipitation frequency estimates w kh 90% confidence intervals (in inches)1 Average recurrence interval(years) Duration L 1 251 02 55 01 002 005 001 000 5-m it 0.370 0.440 0.519 0.574 0.640 0.685 0.727 0.764 0.809 I 0.840 (0.341-0.401) (0.407-0.480) (0.479-0.565) (0.529-0.624) (0.586-0.696) (0.623-0.746) (0.656-0.792) (0.685-0.836) (0.715-0.888) (0.736-0.927) 10-m in 0.591 0.704 0.832 0.918 1.02 1.09 1.16 1.21 1.28 1.32 (0.545-0.641) (0.650-0.767) (0.766-0.905) (0.846-0.998) (0.933-1.11) (0.992-1.19) (1.04-1.26) (1.09-1.32) (1.13-1.40) I (1.16-1.46) -- 15-m rt 0.738 0.885 1.05 1.16 1.29 1.38 1.46 1.53 1.61 1.66 (0.682-0.801) (0.818-0.964) (0.970-1.14) (1.07-1.26) (1.18-1.40) (1.26-1.50) (1.32-1.59) (1.37-1.67) (1.42-1.77) (1.45-1.83) 30-m n 1.01 1.22 1.49 1.68 1.92 2.08 2.24 2.38 2.56 2.69 (0.934-1.10) (1.13-1.33) (1.38-1.63) (1.55-1.83) (1.75-2.08) (1.89-2.26) (2.02-2.44) (2.13-2.60) (2.27-2.81) (2.35-2.97) 60-m rt 1.26 1.53 1.92 2.19 2.55 2.82 3.08 3.34 3.68 3.92 (1.16-1.37) (1.42-1.67) (1.77-2.09) (2.02-2.38) (2.33-2.77) (2.56-3.07) (2.78-3.36) (2.99-3.65) (3.25-4.04) (3.44-4.33) 2-hr 1.50 1.82 2.29 2.65 3.12 3.49 3.87 4.24 4.75 5.15 (1.38-1.63) (1.67-1.99) (2.10-2.51) (2.42-2.89) (2.84-3.41) (3.16-3.82) (3.46-4.23) (3.76-4.65) (4.16-5.24) (4.45-5.69) 3-hr 1.61 1.97 2.48 2.87 3.39 3.80 4.21 4.62 5.20 5.64 (1.48-1.76) (1.81-2.15) (2.28-2.70)_ (2.62-3.12) (3.08-3.69) (3.42-4.14) (3.77-4.59) (4.10-5.06) (4.53-5.71) (4.86-6.22) 6-hr 1.99 2.41 3.04 3.52 4.19 4.73 5.29 5.87 6.68 7.32 (1.83-2.17) (2.22-2.64) (2.79-3.32) (3.22-3.85) (3.81-4.58) (4.26-5.16) (4.72-5.76) (5.17-6.40) (5.78-7.31) (6.25-8.04) 12-hr 2.41 2.92 3.68 4.30 5.16 5.86 6.61 7.40 8.52 9.44 (2.21-2.63) (2.68-3.19) (3.38-4.02) (3.93-4.67) (4.67-5.60) (5.27-6.34) (5.88-7.15) (6.49-8.01) (7.34-9.25) (8.00-10.3) 24-hr 2.88 3.49 4.40 5.14 6.18 7.04 7.94 8.91 10.3 11.4 (2.67-3.12) (3.23-3.78) (4.07-4.77) (4.74-5.55) (5.66-6.68) (6.42-7.60) (7.20-8.58) 1 (8.02-9.63) (9.18-11.1) (10.1-12.4) 2-day 3.39 4.08 5.11 5.93 7.06 7.97 8.92 9.93 11.3 12.5 (3.15-3.65) (3.80-4.40) (4.75-5.50) (5.49-6.38) (6.51-7.59)_ (7.33-8.58) (8.16-9.61) (9.03-10.7) (10.2-12.2) (11.2-13.5) - 3-day 3.59 4.32 5.40 6.25 7.44 8.40 9.40 10.5 11.9 13.1 (3.34-3.85) (4.03-4.65) (5.03-5.80) (5.81-6.71) (6.88-7.98) (7.74-9.02) (8.62-10.1) (9.52-11.3) (10.8-12.9) (11.8-14.2) 4-day 3.79 4.56 5.69 6.58 7.82 8.83 9.88 I 11.0 12.5 13.8 (3.54-4.06) (4.26-4.89) (5.30-6.09) (6.13-7.04)_ (7.25-8.37) (8.15-9.46) (9.07-10.6) (10.0-11.8) (11.3-13.5) (12.4-14.9)_ 7-day 4.32 5.17 6.34 7.28 8.58 9.62 10.7 11.9 13.4 14.7 (4.05-4.61) (4.84-5.53) (5.93-6.77) (6.80-7.77) (7.97-9.15) (8.90-10.3) (9.87-11.4) I (10.9-12.7) (12.2-14.4) (13.3-15.9) 10-day 4.92 5.88 7.13 8.12 9.48 10.6 11.7 12.8 14.4 15.7 (4.63-5.24) (5.52-6.26) (6.69-7.58) (7.60-8.63)_ (8.84-10.1) (9.82-11.2) (10.8-12.4)_ (11.8-13.7) (13.2-15.4) (14.2-16.9) 20-day 6.64 7.87 9.38 10.6 12.2 13.5 14.7 16.1 17.8 19.2 (6.27-7.03) (7.44-8.33) (8.86-9.94) (9.97-11.2) (11.4-12.9) (12.6-14.3) (13.7-15.6) (14.9-17.1) (16.4-19.0) (17.6-20.5) 30-day 8.22 9.70 11.3 12.6 14.2 15.4 16.6 17.8 19.4 20.6 (7.81-8.63) (9.21-10.2) (10.7-11.9) (11.9-13.2) (13.4-14.9) (14.5-16.2) (15.6-17.5) (16.7-18.8) (18.1-20.5) (19.2-21.8) 45-day 10.4 12.2 14.0 15.4 17.2 18.6 19.9 21.2 22.9 24.1 (9.90-10.9) (11.6-12.7) (13.4-14.7) (14.7-16.1) (16.4-18.0)_ (17.6-19.5) (18.9-20.9) (20.0-22.3) (21.5-24.1) (22.6-25.5) 60-day 12.4 14.5 16.5 18.0 19.9 21.3 22.7 24.0 25.6 26.9 (11.9-12.9) (13.9-15.1) (15.8-17.2) (17.2-18.8) (19.0-20.8) (20.3-22.3) (21.5-23.7) (22.7-25.1) (24.2-26.9) (25.3-28.3) 1 Precipitation frequency(PF)estimates in this table are based on frequency analysis of partial duration series(PDS). Num hers in parenthesis are PF estimates at lower and upper bounds of the 90%confidence interval.The probability that precipitation frequency estimates(for a given duration and average recurrence interval)will be greater than the upper bound(or less than the lower bound)is 5%.Estimates at upper bounds are not checked against probable maxim t n precipitation(PM P)estimates and m ay be higher than currently valid PM Pvalues. Please refer to NO AA Atlas 14 docum ait form ae inform ation. Back to Top PF graphical B . POST DEVELOPMENT CURVE NUMBER CALCULATIONS PO/1 TYPE OF AREA SOIL GROUP CN AREA POI TOTAL AREA SF %POI %CN WEIGHTED CN ONSITE OPEN SPACE(FAIR) B 69 11.56 AC 60.36% 41.6 OFFSITE OPEN SPACE(FAIR) B 70 0.00 AC 0.00% 0.0 OFFSITE WOODS(FAIR) B 61 0.00 AC 19.56 AC 0.00% 0.0 81 ONSITE IMPERVIOUS/FUTURE B 98 7.75 AC 38.36% 37.6 OFFSITE IMPERVIOUS B 99 0.245 AC 1.28% 1.3 IMPERVIOUS AREA 40% C . Wet Pond 1 Design Calculation Sheet SA/DA Method PINE RIDGE May 23, 2023 Determine 1 inch Water Quality Volume (WQV) Impervious area (IA) = 40.0% Runoff Coefficient (Rv)= 0.41 Design Storm Depth (RD) = 1 in Drainage Area (A) = 19.55 ac Design Volume (Dv) = 29,096 cf Determine Required Main Pool Surface Area Percent Impervious Cover = 40.0% Calculated Average Depth = 4.17 ft SA/DA = 1.21 Drainage Area = 19.55 ac Required Surface Area = 0.24 ac Required Main Pool Surface Area = 10,343 sf Main Pool Elev. = 907.00 Vegetated Shelf Lower Elev. = 906.50 Vegetated Shelf Upper Elev. = 907.50 Wet Pond 1 Design Calculation Sheet Confirm Pond Volume Provided in Main Pool (Stage-Storage Table) ELEV. CONTOUR INCREMENTAL ACCUMULATED AREA VOLUME VOLUME (ft) (sq ft) (cf) (cf) 901.00 4,264 0 0 902.00 5,509 4,887 4,887 _ 903.00 6,824 6,167 11,053 904.00 8,206 7,515 18,568 905.00 9,655 8,931 27,499 906.00 11,166 10,411 37,909 907.00 13,438 12,302 50,211 Required Forebay Volume (15% of Main Pool 7,532 sf Accumlated Volume) = Confirm Pond Volume Provided in Forebay (Stage- ELEV. CONTOUR INCREMENTAL ACCUMULATED AREA VOLUME VOLUME (ft) (sq ft) (cf) (cf) 901.00 258 0 0 902.00 572 415 415 903.00 962 767 1,182 904.00 1,424 1,193 2,375 905.00 1,955 1,690 4,065 906.00 2,551 2,253 6,318 906.50 2,874 1,356 7,674 Provided Forebay Volume (15% of Main Pool 7,674 sf Accumlated Volume) = Confirm Pond Volume Provided Above Permanent Pool ELEV. CONTOUR INCREMENTAL 'ACCUMULATED AREA VOLUME VOLUME (ft) (sq ft) (cf) (cf) 907.00 16,888 0 0 908.00 19,777 18,333 18,333 909.00 21,775 20,776 39,109 910.00 23,828 22,802 61,910 911.00 25,938 24,883 86,793 Determine WQV Elevation Required ELEVATION ACCUMULATED VOLUME (ft) (sq ft) 908.00 17,806 WQV ELEV 29,096 909.00 37,511 MIN. WQV ELEV. 908.57 Provided WQV Elevation 908.75 Provided WQV Volume (cf) 32,585 WET POND 1 AVERAGE DEPTH EQUATION 3 DEPTH MAX OVER SHELF(FT) 0.50 PERIMETER OF MAIN POOL (FT) 544 WIDTH OF SUBMERGED SHELF(FT) 3.00 VOLUME OF SUBMERGED SHELF(CF) 408.0 VOLUME OF MAIN POOL (CF) 49,754.0 AREA OF MAIN POOL AT BOTTOM OF SHELF(SF) 11,838.00 AVERAGE DEPTH(FT) 4.17 Equation 3. Average depth when the shelf is partially or fully submerged and the shelf is being excluded from the average depth calculation VPP-Vshelf Davg Abottom of shelf Where: Dava = Average depth (feet) Vpp = Main pool volume at permanent pool elevation (feet') Vshen = Volume over the shelf only (feet') — see below Abonom of shelf = Area of main pool at the bottom of the shelf (feet2) Vshelf = 0.5 * Depthmax over shelf* Perimeterperm pool * Widthsubmerged part of shelf Where: Depthmax over shelf = Depth of water at the deep side of the shelf as measured from the permanent pool (feet) Perimeterperm pool = Perimeter of main pool at the bottom of the shelf (feet) Widthsubmorgod part of shelf = Width from the deep side to the dry side of the shelf as measured at permanent pool (feet) WET POND 1 ORFICE SIZING EQUATION PROVIDED WQV(CF) 32,585 MINIMUM DRAWDOWN TIME (S) 172,800 REQUIRED FLOW: Q (CFS) 0.189 COEFFICIENT OF DISCHARGE: CD 0.6 ACCELERATION OF GRAVITY: G (FT/SEC^2) 32.2 DRIVING HEAD: H (FT) 2.00 AREA OF ORIFICE: A (SF) 0.03 AREA OF ORIFICE:A (SI) 3.99 MIN RADIUS OF ORIFICE: R (IN) 1.13 MIN DIAMETER OF ORIFICE: R (IN) 2.25 Orifice Equation for Outlet Flow An orifice is simply a hole. In the design of SCMs. orifices are often used for drawing down the design volume. It is important to determine the size an orifice correctly so that the appropriate detention time provided. The basic equation for discharge from an orifice is: Q = CD A (2 g Ho)0.5 Where: C] = Discharge (cfs) C_ = Coefficient of discharge per Table 6 (unitless) A = Cross-sectional area of orifice entrance (sq ft) g = Acceleration of gravity (32.2 ft/sec2) H_ = Driving head from water surface to centroid orifice (ft) *usually use Hc/3 to compute drawdown through an orifice to reflect the fact that head is decreasing as drawdown occurs' WATER QUALITY VOLUME DRAWDOWN PINE RIDGE- PHASE 2 WET POND 1 PROVIDED WATER QUALITY VOLUME (WQV) DRAWDOWN PROVIDED WQV (CF): 32,584.8 DIAMETER OF ORIFICE (IN): 2.50 PROVIDED WQV ELEVATION 908.75 COEFFICIENT OF DISCHARGE: 0.6 DRIVING HEAD (FT): 0.58 SURFACE AREA AT PROVIDED WQV (SF) 21,775 CROSS SECTIONAL AREA OF ORIFICE (SF): 0.034 DRAWDOWN TIME (HRS) 48.77 DRAWDOWN TIME (DAYS) 2.03 PRECAST CONCRETE OUTLET STRUCTURE FLOTATION CALCULATIONS Pine Ridge Phase 2 December 13,2022 Unit Weight of Water= 62.4 PCF Unit Weight of Concrete= 150 PCF Anti-Buoyancy Factor of Safety= 1.25 Unit Weight of Pipe Material= 557 LB/FT RECTANGULAR STRUCTURE OUTSIDE OUTSIDE WALL WALL BASE LEN (FT) WIDTH (FT) THK(IN) HT(FT) THK(IN) WALLS: 6.50 4.50 6.00 6.80 BASE: 10.00 10.00 24.00 DISPLACED VOLUME/WEIGHT ADDS:(COLLARS) HT(FT) WIDTH (FT) THK(IN) # COLLAR 1: 4 4 12 1 COLLAR 2: 0 0 0 0 EXPOSED BARREL LEN (FT) DIA(IN) 67 24 DISPL. BUOYANT VOLUME WEIGHT FORCE (CF) (LBS) (LBS) WALLS: 199 10,200 12,411 BASE: 200 30,000 12,480 STRUCTURE: 399 40,200 24,891 SOIL: 0 - - INSTALLED TOTALS: 399 40,200 24,891 BUOYANT FORCE= 24,891 LBS ACTING UPWARD STRUCTURE WEIGH+SOIL= 40,200 LBS ACTING DOWNWARD NET FORCE= 15,309 ACTING DOWNWARD ACTUAL FACTOR OF SAFETY= 1.62 D . Hydrograph Summary Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk,Inc.v2024 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) 1 SCS Runoff 40.53 2 718 81,298 <no description> 2 Reservoir 4.924 2 738 78,981 1 908.92 37,640 <no description> 4 SCS Runoff 0.000 2 n/a 0 <no description> 5 Reservoir 0.000 2 n/a 0 4 907.00 0.000 <no description> WET POND 2.gpw Return Period: 1 Year Thursday, 05/23/2024 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Thursday,05/23/2024 Hyd. No. 1 <no description> Hydrograph type = SCS Runoff Peak discharge = 40.53 cfs Storm frequency = 1 yrs Time to peak = 11.97 hrs Time interval = 2 min Hyd. volume = 81,298 cuft Drainage area = 19.560 ac Curve number = 81 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 5.00 min Total precip. = 2.88 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 <no description> Q (cfs) Hyd. No. 1 -- 1 Year Q (cfs) 50.00 50.00 40.00 40.00 30.00 30.00 20.00 20.00 10.00 10.00 0.00 0.00 0 2 4 6 8 10 12 14 16 18 20 22 24 26 Hyd No. 1 Time (hrs) Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Thursday,05/23/2024 Hyd. No. 2 <no description> Hydrograph type = Reservoir Peak discharge = 4.924 cfs Storm frequency = 1 yrs Time to peak = 12.30 hrs Time interval = 2 min Hyd. volume = 78,981 cuft Inflow hyd. No. = 1 - <no description> Max. Elevation = 908.92 ft Reservoir name = POND 1 Max. Storage = 37,640 cuft Storage Indication method used. <no description> Q (cfs) Hyd. No. 2 -- 1 Year Q (cfs) 50.00 50.00 40.00 40.00 30.00 30.00 20.00 20.00 10.00 10.00 0.00 - . - 0.00 0 8 16 24 32 40 48 56 64 72 80 88 Time (hrs) Hyd No. 2 Hyd No. 1 1111111 [ Total storage used = 37,640 cuft E . Hydrograph Summary Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk,Inc.v2024 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) 1 SCS Runoff 0.000 2 n/a 0 <no description> 2 Reservoir 0.000 2 n/a 0 1 907.00 0.000 <no description> 4 SCS Runoff 54.43 2 144 215,757 <no description> 5 Reservoir 48.86 2 148 214,488 4 909.56 52,087 <no description> WET POND 2.gpw Return Period: 100 Year Thursday, 05/23/2024 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Thursday,05/23/2024 Hyd. No. 4 <no description> Hydrograph type = SCS Runoff Peak discharge = 54.43 cfs Storm frequency = 100 yrs Time to peak = 2.40 hrs Time interval = 2 min Hyd. volume = 215,757 cuft Drainage area = 19.560 ac Curve number = 81 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 5.00 min Total precip. = 5.29 in Distribution = SCS 6-Hr Storm duration = 6.00 hrs Shape factor = 484 <no description> Q (cfs) Hyd. No. 4-- 100 Year Q (cfs) 60.00 60.00 — 50.00 50.00 40.00 40.00 30.00 30.00 20.00 20.00 10.00 10.00 0.00 0.00 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 Hyd No. 4 Time (hrs) Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Thursday,05/23/2024 Hyd. No. 5 <no description> Hydrograph type = Reservoir Peak discharge = 48.86 cfs Storm frequency = 100 yrs Time to peak = 2.47 hrs Time interval = 2 min Hyd. volume = 214,488 cuft Inflow hyd. No. = 4 - <no description> Max. Elevation = 909.56 ft Reservoir name = POND 1 Max. Storage = 52,087 cuft Storage Indication method used. <no description> Q (cfs) Hyd. No. 5-- 100 Year Q (cfs) 60.00 60.00 50.00 1 50.00 40.00 40.00 30.00 30.00 20.00 20.00 10.00 - 10.00 0.00 - 0.00 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 Time (hrs) Hyd No. 5 Hyd No. 4 1111111 Total storage used = 52,087 cuft F . Hydrograph Return Period Recap draflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk,Inc.v2024 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 SCS Runoff 40.53 0.000 <no description> 2 Reservoir 1 4.924 0.000 <no description> 4 SCS Runoff 0.000 54.43 <no description> 5 Reservoir 4 0.000 48.86 <no description> Proj. file: WET POND 2.gpw Thursday, 05/23/2024 Pond Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Thursday,05/23/2024 Pond No. 1 - POND 1 Pond Data Contours-User-defined contour areas.Conic method used for volume calculation.Begining Elevation=907.00 ft Stage/Storage Table Stage(ft) Elevation(ft) Contour area(sqft) Incr.Storage(cuft) Total storage(cuft) 0.00 907.00 16,888 0 0 0.50 907.50 18,800 8,917 8,917 1.00 908.00 19,777 9,642 18,559 2.00 909.00 21,775 20,766 39,325 3.00 910.00 23,828 22,792 62,117 4.00 911.00 25,938 24,873 86,990 Culvert/Orifice Structures Weir Structures [A] [B] [C] [PrfRsr] [A] [B] [C] [D] Rise(in) = 42.00 2.50 0.00 0.00 Crest Len(ft) = 20.00 0.00 0.00 0.00 Span(in) = 42.00 2.50 0.00 0.00 Crest El.(ft) = 908.75 0.00 0.00 0.00 No.Barrels = 1 1 0 0 Weir Coeff. = 3.33 3.33 3.33 3.33 Invert El.(ft) = 901.00 907.00 0.00 0.00 Weir Type = 1 --- --- --- Length(ft) = 10.00 0.10 0.00 0.00 Multi-Stage = Yes No No No Slope(%) = 1.00 0.10 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 Contour) Multi-Stage = n/a Yes 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) 4.00 1 911.00 3.00 910.00 2.00 909.00 1.00 908.00 0.00 ` ' 907.00 0.0 10.0 20.0 30.0 40.0 50.0 60.0 70.0 80.0 90.0 100.0 110.0 120.0 130.0 Total Q Discharge(cfs) G . A Allied Design Inc. PROJECT NAME Pine Ridge-Phase 2 � Outlet Stabilization CIVIL ENGINEERING ❖ LAND SURVEYING PROJECT NO. 23-011 SHEET 1 OF 1 4720 Kester Mill Road BY WAB DATE 27-Oct-23 Winston-Salem,North Carolina 27103 CHECKED BY SMC REV 27-Oct-23 Ph.336.765.2377 e•Fax 336.760.8886 Outlet Stabilization 3 o E 1.1. I I!, Outlet W = Do + La 9� • I ,iiEl.it ill�iii�ll. pipe I I •uiuii !III * I. diameter(Do) 1 I ': rl : ' I • .j ii:: I j.;.i4 r 1 ■um dai La -� 80 -.... w ■0■1 *Aar T ilwater O.5Do - _ IITri ■■ �,irUlru', r_. Iri�1i;11! -1- I--- ■ -- -- - y Lal:riilln' ■ -al��l; 7f 1 I .-_ 1 w iii;lr�ICI" i pco !I ■ B : r0.1%1' 'i nl I,l'' 60 I-Ii■f_: I-.--_...■ r *rlrs.■: ..I vnu 211 \.84(9 0 -.. ai■I-'I EI I - - _..---1-- * "�e it I' ... 4- uuiii 1 V� 50 -.. -w I 1■ 1=_I_� .---a----: • 4P_i r1. *r/'U1/1111111111111 \fi 1 I I __. _. �, ''/ ■;1.V. Vd uII1111mu1111 _p\� - I--`- . .. Irl�..1 r * I211■11111111111111II. • - I-,--- • --II ��N • �r1■IIIIIIIIlIII11I11 -_ •_ -- -I_L 1_.. • 'FBI d/jr�ll ■■1■1 IIII IIIIIIIIIG 40 _� rr,r w ■■I■111 IU':n/ 4 I ( • /I■►4r 1v ■-■I■w ■■I II,11111'1 _ I p 1i/ r ■' w •■1 AIIIJIIIIJI 3 _ ti 1111 'S �i�■r�/� FEE •■1 I■inn)IlllP" , w. i .I �V�.� _mow ■■I■Irllll Jv!Idlir s •�%- III -7 ■ w r/11S" llllllAl NI: !t/_ I /1 ■ ■ iw ys ir'JIII!Ilv',1 EMU': i/, - 711 ■ ■ ... 4 �I•INIIr';Mill B■ •4-a - I_�I ■ ■-- ,��1%All;r• ilill!1111 20 Iww■wlwwww- •/%II!.•I�Ir I. 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Outlet Pipe Discharge d50 La W dmax apron NCDOT Diameter thickness riprap (in) (cfs) (ft) (ft) (ft) (ft) (ft) Class 100 42 91.96 0.80 27.0 30.5 1.2 1.8 1 200 15 4.79 0• .30 8.0 9• .3 0.5 0.7 A • • 300 18 0.38 0.30 10.0 11.5 0.5 0.7 A Pond 24 7.50 0• .40 13.0 15• .0 0.6 0.9 B •TAKEN FROM THE NORTH CAROLINA EROSION AND SEDIMENT CONTROL H . DITCH SCHEDULE-25 YEAR STORM DESIGN PINE RIDGE-PHASE 2 RURAL HALL,NORTH CAROLINA October 27,2023 z ¢ 0 = a CC W w I F- O E w 0 Q oz a w a o w u' }} H H w O DU z 5 K OJ O 0 F o x z E- LL 00 Z x x 0 w I O z a 0 Q J w Z W o H H0 w dw Jw z Q 0 0 Z 0 F 00 z 0 0 00 Cl) 0 > J (I) (AC) (IN/HR) (CFS) (FT/FT) (FT) ("X":1) (FT) (FPS) 1 0.09 0.55 5 7.68 0.38 15.00% 2 3 0.07 2.38 S75 D 2 0.14 0.55 5 7.68 0.59 16.00% 2 3 0.09 3.05 S75 D 3 0.69 0.55 5 7.68 2.91 2.40% 2 3 0.40 2.26 S75 D 4 0.51 0.55 5 7.68 2.15 2.00% 2 3 0.38 1.81 S75 D 5 0.14 0.55 5 7.68 0.59 2.00% 2 3 0.21 1.07 S75 D 6 0.54 0.55 5 7.68 2.28 2.25% 2 3 0.37 1.98 S75 D 7 0.08 0.55 5 7.68 0.34 2.50% 2 3 0.15 0.95 S75 D 8 0.23 0.55 5 7.68 0.97 6.67% 2 3 0.16 2.47 S75 D 9 1.04 0.55 5 7.68 4.39 4.00% 2 3 0.39 3.51 S75 D 10 0.47 0.55 5 7.68 1.99 1.70% 2 3 0.39 1.61 S75 D 11 0.09 0.55 5 7.68 0.38 3.25% 2 3 0.14 1.14 S75 D 12 0.56 0.55 5 7.68 2.37 3.50% 2 3 0.31 2.56 S75 D 13 0.16 0.55 5 7.68 0.68 2.00% 2 3 0.22 1.14 S75 D 14 0.15 0.55 5 7.68 0.63 4.45% 2 3 0.15 1.67 S75 D 15 0.24 0.55 5 7.68 1.01 5.00% 2 3 0.18 2.17 S75 D 16 0.19 0.55 5 7.68 0.80 1.60% 2 3 0.26 1.08 S75 D 17 0.47 0.55 5 7.68 1.99 1.60% 2 3 0.40 1.56 S75 D 18 0.80 0.55 5 7.68 3.38 1.50% 2 3 0.52 1.84 S75 D 19 0.61 0.55 5 7.68 2.58 2.00% 2 3 0.41 1.95 S75 D 20 0.30 0.55 5 7.68 1.27 2.85% 2 3 0.26 1.78 S75 D 21 0.15 0.55 5 7.68 0.63 2.22% 2 3 0.21 1.16 S75 D 22 0.10 0.55 5 7.68 0.42 2.22% 2 3 0.17 0.98 S75 D NORTH North American G reen AMERICAN 5401 St. Wendel-Cynthiana Rd. Poseyville, Indiana 47633 GREEN Tel. 800.772.2040 > Fax 812.867.0247 wwwnagreen.com ECM D Sv7.0 CHANNEL ANALYSIS >>>Ditch#1 Name Ditch#1 Discharge 0.38 Channel Slope 0 .15 Channel Bottom Width 2 Left Side Slope 3 Right Side Slope 3 Low Flow Liner Retardence Class D 2-6 in Vegetation Type M x(Sod and Bunch) Vegetation Density F air 50-64% Soil Type Clay Loam(CL) Unreinforced Vegetation ePhase R iach D scharge V locity Normal Mannings N Permissible Calculated Safety Renarks Staple D epth Shear Stress Shear Stress Factor Pattern Unreinforced Straight 0 .38 cfs 2 .38 ft/s 0 .07 ft 0 .039 4 lbs/ft2 0 .66 lbs/ft2 6 .08 S TABLE -- Vegetation Underlying Straight 0 .38 cfs 2 .38 ft/s 0 .07 ft 0 .039 2 .32 Ibs/ft2 0 .6 Ibs/ft2 3 .9 S TABLE Substrate ElNORTH North American G reen AMERICAN 5401 St. Wendel-Cynthiana Rd. Poseyville, Indiana 47633 GREEN Tel. 800.772.2040 > Fax 812.867.0247 wwwnagreen.com ECM D Sv7.0 CHANNEL ANALYSIS >>>Ditch#2 Name Ditch#2 Discharge 0.59 Channel Slope 0 .16 Channel Bottom Width 2 Left Side Slope 3 Right Side Slope 3 Low Flow Liner Retardence Class D 2-6 in Vegetation Type M x(Sod and Bunch) Vegetation Density F air 50-64% Soil Type Clay Loam(CL) Unreinforced Vegetation ePhase R iach D scharge V locity Normal Mannings N Permissible Calculated Safety Renarks Staple D epth Shear Stress Shear Stress Factor Pattern Unreinforced Straight 0 .59 cfs 3 .05 ft/s 0 .09 ft 0 .035 4 lbs/ft2 0 .85 lbs/ft2 4 .69 S TABLE Vegetation Underlying Straight 0 .59 cfs 3 .05 ft/s 0 .09 ft 0 .035 1 .91 Ibs/ft2 0 .76 Ibs/ft2 2 .52 S TABLE Substrate NORTH North American G reen AMERICAN 5401 St. Wendel-Cynthiana Rd. Poseyville, Indiana 47633 GREEN Tel. 800.772.2040 > Fax 812.867.0247 wwwnagreen.com ECM D Sv7.0 CHANNEL ANALYSIS >>>Ditch#3 Name Ditch#3 Discharge 2.91 Channel Slope 0 .024 Channel Bottom Width 2 Left Side Slope 3 Right Side Slope 3 Low Flow Liner Retardence Class D 2-6 in Vegetation Type M x(Sod and Bunch) Vegetation Density F air 50-64% Soil Type Clay Loam(CL) Unreinforced Vegetation ePhase R iach D scharge V locity Normal Mannings N Permissible Calculated Safety Renarks Staple D epth Shear Stress Shear Stress Factor Pattern Unreinforced Straight 2 .91 cfs 2 .26 ft/s 0 .4 ft 0 .044 4 lbs/ft2 0 .6 lbs/ft2 6 .64 S TABLE -- Vegetation Underlying Straight 2 .91 cfs 2 .26 ft/s 0 .4 ft 0 .044 3 .04 Ibs/ft2 0 .43 Ibs/ft2 7 .14 S TABLE Substrate NORTH North American G reen AMERICAN 5401 St. Wendel-Cynthiana Rd. Poseyville, Indiana 47633 GREEN Tel. 800.772.2040 > Fax 812.867.0247 wwwnagreen.com ECM D Sv7.0 CHANNEL ANALYSIS >>>Ditch#4 Name Ditch#4 Discharge 2.15 Channel Slope 0 .02 Channel Bottom Width 2 Left Side Slope 3 Right Side Slope 3 Low Flow Liner Retardence Class D 2-6 in Vegetation Type M x(Sod and Bunch) Vegetation Density F air 50-64% Soil Type Clay Loam(CL) Unreinforced Vegetation ePhase R iach D scharge V locity Normal Mannings N Permissible Calculated Safety Renarks Staple D epth Shear Stress Shear Stress Factor Pattern Unreinforced Straight 2 .15 cfs 1 .81 ft/s 0 .38 ft 0 .048 4 lbs/ft2 0 .47 lbs/ft2 8 .48 S TABLE Vegetation Underlying Straight 2 .15 cfs 1 .81 ft/s 0 .38 ft 0 .048 3 .66 Ibs/ft2 0 .34 Ibs/ft2 1 0.87 S TABLE Substrate ElNORTH North American G leen AMERICAN 5401 St. Wendel-Cynthiana Rd. Poseyville, Indiana 47633 GREEN Tel. 800.772.2040 > Fax 812.867.0247 wwwnagreen.com ECM D Sv7.0 CHANNEL ANALYSIS >>>Ditch#5 Name Ditch#5 Discharge 0.59 Channel Slope 0 .02 Channel Bottom Width 2 Left Side Slope 3 Right Side Slope 3 Low Flow Liner Retardence Class D 2-6 in Vegetation Type M x(Sod and Bunch) Vegetation Density F air 50-64% Soil Type Clay Loam(CL) Unreinforced Vegetation ePhase R iach D scharge V locity Normal Mannings N Permissible Calculated Safety Remarks Staple D epth Shear Stress Shear Stress Factor Pattern Unreinforced Straight 0 .59 cfs 1 .07 ft/s 0 .21 ft 0 .059 4 Ibs/ft2 0 .26 lbs/ft2 1 5.35 S TABLE Vegetation Underlying Straight 0 .59 cfs 1 .07 ft/s 0 .21 ft 0 .059 4 Ibs/ft2 0 .21 Ibs/ft2 1 9.4 S TABLE Substrate NORTH North American G reen AMERICAN 5401 St. Wendel-Cynthiana Rd. Poseyville, Indiana 47633 GREEN Tel. 800.772.2040 > Fax 812.867.0247 wwwnagreen.com ECM D Sv7.0 CHANNEL ANALYSIS >>>Ditch#6 Name Ditch#6 Discharge 2.28 Channel Slope 0 .0225 Channel Bottom Width 2 Left Side Slope 3 Right Side Slope 3 Low Flow Liner Retardence Class D 2-6 in Vegetation Type M x(Sod and Bunch) Vegetation Density F air 50-64% Soil Type Clay Loam(CL) Unreinforced Vegetation ePhase R iach D scharge V locity Normal Mannings N Permissible Calculated Safety Remarks Staple D epth Shear Stress Shear Stress Factor Pattern Unreinforced Straight 2 .28 cfs 1 .98 ft/s 0 .37 ft 0 .046 4 lbs/ft2 0 .52 lbs/ft2 7 .7 S TABLE Vegetation Underlying Straight 2 .28 cfs 1 .98 ft/s 0 .37 ft 0 .046 3 .38 Ibs/ft2 0 .37 Ibs/ft2 9 .07 S TABLE Substrate NORTH North American G reen AMERICAN 5401 St. Wendel-Cynthiana Rd. Poseyville, Indiana 47633 GREEN Tel. 800.772.2040 > Fax 812.867.0247 wwwnagreen.com ECM D Sv7.0 CHANNEL ANALYSIS >>>Ditch#7 Name Ditch#7 Discharge 0.34 Channel Slope 0 .025 Channel Bottom Width 2 Left Side Slope 3 Right Side Slope 3 Low Flow Liner Retardence Class D 2-6 in Vegetation Type M x(Sod and Bunch) Vegetation Density F air 50-64% Soil Type Clay Loam(CL) Unreinforced Vegetation Normal Permissible Calculated Safety Staple ePhase R iach D scharge V locity Mannings N Renarks D epth Shear Stress Shear Stress Factor Pattern Unreinforced Straight 0 .34 cfs 0 .95 ft/s 0 .15 ft 0 .061 4 lbs/ft2 0 .23 lbs/ft2 1 7.5 S TABLE -- Vegetation Underlying Straight 0 .34 cfs 0 .95 ft/s 0 .15 ft 0 .061 4 Ibs/ft2 0 .19 Ibs/ft2 2 1 S TABLE Substrate NORTH North American G reen AMERICAN 5401 St. Wendel-Cynthiana Rd. Poseyville, Indiana 47633 GREEN Tel. 800.772.2040 > Fax 812.867.0247 wwwnagreen.com ECM D Sv7.0 CHANNEL ANALYSIS >>>Ditch#8 Name Ditch#8 Discharge 0.97 Channel Slope 0 .0667 Channel Bottom Width 2 Left Side Slope 3 Right Side Slope 3 Low Flow Liner Retardence Class D 2-6 in Vegetation Type M x(Sod and Bunch) Vegetation Density F air 50-64% Soil Type Clay Loam(CL) Unreinforced Vegetation ePhase R iach D scharge V locity Normal Mannings N Permissible Calculated Safety Renarks Staple D epth Shear Stress Shear Stress Factor Pattern Unreinforced Straight 0 .97 cfs 2 .47 ft/s 0 .16 ft 0 .04 4 lbs/ft2 0 .66 lbs/ft2 6 .07 S TABLE Vegetation Underlying Straight 0 .97 cfs 2 .47 ft/s 0 .16 ft 0 .04 2 .49 Ibs/ft2 0 .54 Ibs/ft2 4 .59 S TABLE Substrate NORTH North American G reen AMERICAN 5401 St. Wendel-Cynthiana Rd. Poseyville, Indiana 47633 GREEN Tel. 800.772.2040 > Fax 812.867.0247 wwwnagreen.com ECM D Sv7.0 CHANNEL ANALYSIS >>>Ditch#9 Name Ditch#9 Discharge 4.39 Channel Slope 0 .04 Channel Bottom Width 2 Left Side Slope 3 Right Side Slope 3 Low Flow Liner Retardence Class D 2-6 in Vegetation Type M x(Sod and Bunch) Vegetation Density F air 50-64% Soil Type Clay Loam(CL) Unreinforced Vegetation ePhase R iach D scharge V locity Normal Mannings N Permissible Calculated Safety Renarks Staple D epth Shear Stress Shear Stress Factor Pattern Unreinforced Straight 4 .39 cfs 3 .51 ft/s 0 .39 ft 0 .036 4 lbs/ft2 0 .98 lbs/ft2 4 .07 S TABLE Vegetation Underlying Straight 4 .39 cfs 3 .51 ft/s 0 .39 ft 0 .036 2 .05 Ibs/ft2 0 .7 Ibs/ft2 2 .94 S TABLE Substrate ElNORTH North American G leen AMERICAN 5401 St. Wendel-Cynthiana Rd. Poseyville, Indiana 47633 GREEN Tel. 800.772.2040 > Fax 812.867.0247 wwwnagreen.com ECM D Sv7.0 CHANNEL ANALYSIS >>>Ditch#10 Name Ditch#10 Discharge 1.99 Channel Slope 0 .017 Channel Bottom Width 2 Left Side Slope 3 Right Side Slope 3 Low Flow Liner Retardence Class D 2-6 in Vegetation Type M x(Sod and Bunch) Vegetation Density F air 50-64% Soil Type Clay Loam(CL) Unreinforced Vegetation ePhase R iach D scharge V locity Normal Mannings N Permissible Calculated Safety Renarks Staple D epth Shear Stress Shear Stress Factor Pattern Unreinforced Straight 1 .99 cfs 1 .61 ft/s 0 .39 ft 0 .051 4 Ibs/ft2 0 .41 lbs/ft2 9 .67 S TABLE Vegetation Underlying Straight 1 .99 cfs 1 .61 ft/s 0 .39 ft 0 .051 4 Ibs/ft2 0 .29 Ibs/ft2 1 3.63 S TABLE Substrate NORTH North American G reen AMERICAN 5401 St. Wendel-Cynthiana Rd. Poseyville, Indiana 47633 GREEN Tel. 800.772.2040 > Fax 812.867.0247 wwwnagreen.com ECM D Sv7.0 CHANNEL ANALYSIS >>>Ditch#11 Name Ditch#11 Discharge 0.38 Channel Slope 0 .0325 Channel Bottom Width 2 Left Side Slope 3 Right Side Slope 3 Low Flow Liner Retardence Class D 2-6 in Vegetation Type M x(Sod and Bunch) Vegetation Density F air 50-64% Soil Type Clay Loam(CL) Unreinforced Vegetation ePhase R iach D scharge V locity Normal Mannings N Permissible Calculated Safety Renarks Staple D epth Shear Stress Shear Stress Factor Pattern Unreinforced Straight 0 .38 cfs 1 .14 ft/s 0 .14 ft 0 .056 4 lbs/ft2 0 .28 lbs/ft2 1 4.3 S TABLE Vegetation Underlying Straight 0 .38 cfs 1 .14 ft/s 0 .14 ft 0 .056 4 Ibs/ft2 0 .24 Ibs/ft2 1 7.02 S TABLE Substrate NORTH North American G reen AMERICAN 5401 St. Wendel-Cynthiana Rd. Poseyville, Indiana 47633 GREEN Tel. 800.772.2040 > Fax 812.867.0247 wwwnagreen.com ECM D Sv7.0 CHANNEL ANALYSIS >>>Ditch#12 Name Ditch#12 Discharge 2.37 Channel Slope 0 .035 Channel Bottom Width 2 Left Side Slope 3 Right Side Slope 3 Low Flow Liner Retardence Class D 2-6 in Vegetation Type M x(Sod and Bunch) Vegetation Density F air 50-64% Soil Type Clay Loam(CL) Unreinforced Vegetation ePhase R iach D scharge V locity Normal Mannings N Permissible Calculated Safety Renarks Staple D epth Shear Stress Shear Stress Factor Pattern Unreinforced Straight 2 .37 cfs 2 .56 ft/s 0 .31 ft 0 .041 4 lbs/ft2 0 .69 lbs/ft2 5 .82 S TABLE -- Vegetation Underlying Straight 2 .37 cfs 2 .56 ft/s 0 .31 ft 0 .041 2 .64 Ibs/ft2 0 .51 Ibs/ft2 5 .2 S TABLE Substrate NORTH North American G reen AMERICAN 5401 St. Wendel-Cynthiana Rd. Poseyville, Indiana 47633 GREEN Tel. 800.772.2040 > Fax 812.867.0247 wwwnagreen.com ECM D Sv7.0 CHANNEL ANALYSIS >>>Ditch#13 Name Ditch#13 Discharge 0.68 Channel Slope 0 .02 Channel Bottom Width 2 Left Side Slope 3 Right Side Slope 3 Low Flow Liner Retardence Class D 2-6 in Vegetation Type M x(Sod and Bunch) Vegetation Density F air 50-64% Soil Type Clay Loam(CL) Unreinforced Vegetation ePhase R iach D scharge V locity Normal Mannings N Permissible Calculated Safety Remarks Staple D epth Shear Stress Shear Stress Factor Pattern Unreinforced Straight 0 .68 cfs 1 .14 ft/s 0 .22 ft 0 .058 4 lbs/ft2 0 .28 lbs/ft2 1 4.36 S TABLE Vegetation Underlying Straight 0 .68 cfs 1 .14 ft/s 0 .22 ft 0 .058 4 Ibs/ft2 0 .22 Ibs/ft2 1 8.35 S TABLE Substrate NORTH North American G reen AMERICAN 5401 St. Wendel-Cynthiana Rd. Poseyville, Indiana 47633 GREEN Tel. 800.772.2040 > Fax 812.867.0247 wwwnagreen.com ECM D Sv7.0 CHANNEL ANALYSIS >>>Ditch#14 Name Ditch#14 Discharge 0.63 Channel Slope 0 .0445 Channel Bottom Width 2 Left Side Slope 3 Right Side Slope 3 Low Flow Liner Retardence Class D 2-6 in Vegetation Type M x(Sod and Bunch) Vegetation Density F air 50-64% Soil Type Clay Loam(CL) Unreinforced Vegetation ePhase R iach D scharge V locity Normal Mannings N Permissible Calculated Safety Renarks Staple D epth Shear Stress Shear Stress Factor Pattern Unreinforced Straight 0 .63 cfs 1 .67 ft/s 0 .15 ft 0 .047 4 lbs/ft2 0 .43 lbs/ft2 9 .39 S TABLE Vegetation Underlying Straight 0 .63 cfs 1 .67 ft/s 0 .15 ft 0 .047 3 .52 Ibs/ft2 0 .35 Ibs/ft2 9 .99 S TABLE Substrate NORTH North American G reen AMERICAN 5401 St. Wendel-Cynthiana Rd. Poseyville, Indiana 47633 GREEN Tel. 800.772.2040 > Fax 812.867.0247 wwwnagreen.com ECM D Sv7.0 CHANNEL ANALYSIS >>>Ditch#15 Name Ditch#15 Discharge 1.01 Channel Slope 0 .05 Channel Bottom Width 2 Left Side Slope 3 Right Side Slope 3 Low Flow Liner Retardence Class D 2-6 in Vegetation Type M x(Sod and Bunch) Vegetation Density F air 50-64% Soil Type Clay Loam(CL) Unreinforced Vegetation ePhase R iach D scharge V locity Normal Mannings N Permissible Calculated Safety Renarks Staple D epth Shear Stress Shear Stress Factor Pattern Unreinforced Straight 1 .01 cfs 2 .17 ft/s 0 .18 ft 0 .043 4 lbs/ft2 0 .57 lbs/ft2 7 .03 S TABLE Vegetation Underlying Straight 1 .01 cfs 2 .17 ft/s 0 .18 ft 0 .043 2 .85 Ibs/ft2 0 .46 Ibs/ft2 6 .2 S TABLE Substrate ElNORTH North American G leen AMERICAN 5401 St. Wendel-Cynthiana Rd. Poseyville, Indiana 47633 GREEN Tel. 800.772.2040 > Fax 812.867.0247 wwwnagreen.com ECM D Sv7.0 CHANNEL ANALYSIS >>>Ditch#16 Name Ditch#16 Discharge 0.8 Channel Slope 0 .016 Channel Bottom Width 2 Left Side Slope 3 Right Side Slope 3 Low Flow Liner Retardence Class D 2-6 in Vegetation Type M x(Sod and Bunch) Vegetation Density F air 50-64% Soil Type Clay Loam(CL) Unreinforced Vegetation ePhase R iach D scharge V locity Normal Mannings N Permissible Calculated Safety Renarks Staple D epth Shear Stress Shear Stress Factor Pattern Unreinforced Straight 0 .8 cfs 1 .08 ft/s 0 .26 ft 0 .06 4 Ibs/ft2 0 .26 lbs/ft2 1 5.17 S TABLE Vegetation Underlying Straight 0 .8 cfs 1 .08 ft/s 0 .26 ft 0 .06 4 Ibs/ft2 0 .2 Ibs/ft2 1 9.94 S TABLE Substrate NORTH North American G reen AMERICAN 5401 St. Wendel-Cynthiana Rd. Poseyville, Indiana 47633 GREEN Tel. 800.772.2040 > Fax 812.867.0247 wwwnagreen.com ECM D Sv7.0 CHANNEL ANALYSIS >>>Ditch#17 Name Ditch#17 Discharge 1.99 Channel Slope 0 .016 Channel Bottom Width 2 Left Side Slope 3 Right Side Slope 3 Low Flow Liner Retardence Class D 2-6 in Vegetation Type M x(Sod and Bunch) Vegetation Density F air 50-64% Soil Type Clay Loam(CL) Unreinforced Vegetation ePhase R iach D scharge V locity Normal Mannings N Permissible Calculated Safety Remarks Staple D epth Shear Stress Shear Stress Factor Pattern Unreinforced Straight 1 .99 cfs 1 .56 ft/s 0 .4 ft 0 .052 4 lbs/ft2 0 .4 lbs/ft2 1 0.03 S TABLE Vegetation Underlying Straight 1 .99 cfs 1 .56 ft/s 0 .4 ft 0 .052 4 Ibs/ft2 0 .28 Ibs/ft2 1 4.2 S TABLE Substrate NORTH North American G reen AMERICAN 5401 St. Wendel-Cynthiana Rd. Poseyville, Indiana 47633 GREEN Tel. 800.772.2040 > Fax 812.867.0247 wwwnagreen.com ECM D Sv7.0 CHANNEL ANALYSIS >>>Ditch#18 Name Ditch#18 Discharge 3.38 Channel Slope 0 .015 Channel Bottom Width 2 Left Side Slope 3 Right Side Slope 3 Low Flow Liner Retardence Class D 2-6 in Vegetation Type M x(Sod and Bunch) Vegetation Density F air 50-64% Soil Type Clay Loam(CL) Unreinforced Vegetation ePhase R iach D scharge V locity Normal Mannings N Permissible Calculated Safety Renarks Staple D epth Shear Stress Shear Stress Factor Pattern Unreinforced Straight 3 .38 cfs 1 .84 ft/s 0 .52 ft 0 .049 4 lbs/ft2 0 .48 lbs/ft2 8 .26 S TABLE Vegetation Underlying Straight 3 .38 cfs 1 .84 ft/s 0 .52 ft 0 .049 3 .75 Ibs/ft2 0 .33 Ibs/ft2 1 1.5 S TABLE Substrate NORTH North American G reen AMERICAN 5401 St. Wendel-Cynthiana Rd. Poseyville, Indiana 47633 GREEN Tel. 800.772.2040 > Fax 812.867.0247 wwwnagreen.com ECM D Sv7.0 CHANNEL ANALYSIS >>>Ditch#19 Name Ditch#19 Discharge 2.58 Channel Slope 0 .02 Channel Bottom Width 2 Left Side Slope 3 Right Side Slope 3 Low Flow Liner Retardence Class D 2-6 in Vegetation Type M x(Sod and Bunch) Vegetation Density F air 50-64% Soil Type Clay Loam(CL) Unreinforced Vegetation ePhase R iach D scharge V locity Normal Mannings N Permissible Calculated Safety Renarks Staple D epth Shear Stress Shear Stress Factor Pattern Unreinforced Straight 2 .58 cfs 1 .95 ft/s 0 .41 ft 0 .047 4 lbs/ft2 0 .51 lbs/ft2 7 .82 S TABLE Vegetation Underlying Straight 2 .58 cfs 1 .95 ft/s 0 .41 ft 0 .047 3 .47 Ibs/ft2 0 .36 Ibs/ft2 9 .64 S TABLE Substrate ElNORTH North American G leen AMERICAN 5401 St. Wendel-Cynthiana Rd. Poseyville, Indiana 47633 GREEN Tel. 800.772.2040 > Fax 812.867.0247 wwwnagreen.com ECM D Sv7.0 CHANNEL ANALYSIS >>>Ditch#20 Name Ditch#20 Discharge 1.27 Channel Slope 0 .0285 Channel Bottom Width 2 Left Side Slope 3 Right Side Slope 3 Low Flow Liner Retardence Class D 2-6 in Vegetation Type M x(Sod and Bunch) Vegetation Density F air 50-64% Soil Type Clay Loam(CL) Unreinforced Vegetation ePhase R iach D scharge V locity Normal Mannings N Permissible Calculated Safety Renarks Staple D epth Shear Stress Shear Stress Factor Pattern Unreinforced Straight 1 .27 cfs 1 .78 ft/s 0 .26 ft 0 .048 4 lbs/ft2 0 .46 lbs/ft2 8 .74 S TABLE -- Vegetation Underlying Straight 1 .27 cfs 1 .78 ft/s 0 .26 ft 0 .048 3 .55 Ibs/ft2 0 .35 Ibs/ft2 1 0.15 S TABLE Substrate NORTH North American Green AMERICAN 5401 St. Wendel-Cynthiana Rd. Poseyville, Indiana 47633 GREEN Tel. 800.772.2040 >Fax 812.867.0247 www.nagreen.com ECMDS v7.0 CHANNEL ANALYSIS >>>Ditch#21 Name Ditch#21 Discharge 0.63 Channel Slope 0.022 Channel Bottom Width 2 Left Side Slope 3 Right Side Slope 3 Low Flow Liner Retardence Class D 2-6 in Vegetation Type Mix(Sod and Bunch) Vegetation Density Fair 50-64% Soil Type Clay Loam(CL) Unreinforced Vegetation Normal Permissible Calculated Safety Staple Phase Reach Discharge Velocity Mannings N Remarks Depth Shear Stress Shear Stress Factor Pattern Unreinforced Straight 0.63 cfs 1.16 ft/s 0.21 ft 0.057 4 lbs/ft2 0.28 lbs/ft2 14.08 STABLE -- Vegetation Underlying Straight 0.63 cfs 1.16 ft/s 0.21 ft 0.057 4 lbs/ft2 0.23 lbs/ft2 17.78 STABLE Substrate NORTH North American Green AMERICAN 5401 St. Wendel-Cynthiana Rd. Poseyville, Indiana 47633 GREEN Tel. 800.772.2040 >Fax 812.867.0247 www.nagreen.com ECMDS v7.0 CHANNEL ANALYSIS >>>Ditch#22 Name Ditch#22 Discharge 0.42 Channel Slope 0.022 Channel Bottom Width 2 Left Side Slope 3 Right Side Slope 3 Low Flow Liner Retardence Class D 2-6 in Vegetation Type Mix(Sod and Bunch) Vegetation Density Fair 50-64% Soil Type Clay Loam(CL) Unreinforced Vegetation Normal Permissible Calculated Safety Staple Phase Reach Discharge Velocity Mannings N Remarks Depth Shear Stress Shear Stress Factor Pattern Unreinforced Straight 0.42 cfs 0.98 ft/s 0.17 ft 0.061 4 lbs/ft2 0.23 lbs/ft2 17.05 STABLE Vegetation Underlying Straight 0.42 cfs 0.98 ft/s 0.17 ft 0.061 4 lbs/ft2 0.19 lbs/ft2 20.91 STABLE Substrate I . Hydrologic Soil Group—Forsyth County, North Carolina a a § 561900 562000 562100 562200 562300 562400 562500 36°14'8"N 36°14'8"N ".".1A -ie- 1 ' - - _ 4 .141r, SmD _ \ .. ' PI / PcF2 -._ ,` 11110 # r 7 g Ic2 FcC�2 8 ir , ,-!�' FcC2 <.Te_ s P riS - ToB2 . 1 FcD2• 4 4 PoF li L; TmC .41111 - TmB P,cF2 . Ifi 1 k-'istr‘ 1 Toe-2 . . Ai Too I „.r I PcF2 111' TcgO ., 4; t ToB2 ii ---..... lig ' - - PcF2- ToC2 - •' QoC�2 1,1 r.!it r n En 0 t-pmay ootl be valid at this sc•IC�o . ' ( it / 36°13'37'N I 36°13'37'N 561900 562000 562100 562200 562300 562400 562500 Map scale:1:4,790 if printed on A portrait(8.5"x 11")sheet Meters m N 0 50 100 200 300 $ Feet 0 200 400 800 1200 Map projection:Web Mercator Comer coordinates:WGS84 Edge tics:UTM Zone 17N WGS84 USDA Natural Resources Web Soil Survey 9/18/2023 111-1-111 Conservation Service National Cooperative Soil Survey Page 1 of 4 Hydrologic Soil Group—Forsyth County,North Carolina MAP LEGEND MAP INFORMATION Area of Interest(AOI) p c The soil surveys that comprise your AOI were mapped at Area of Interest(AOI) 1:15,800. 0 C/D Soils • D Warning:Soil Map may not be valid at this scale. Soil Rating Polygons l A p Not rated or not available Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil n A/D Water Features line placement.The maps do not show the small areas of Streams and Canals contrasting soils that could have been shown at a more detailed n B scale. Transportation Q B/D r4-1. Rails Please rely on the bar scale on each map sheet for map n C measurements. ti Interstate Highways C/D US Routes Source of Map: Natural Resources Conservation Service Web Soil Survey URL: 0 D Major Roads Coordinate System: Web Mercator(EPSG:3857) n Not rated or not available Local Roads Maps from the Web Soil Survey are based on the Web Mercator Soil Rating Lines Background projection,which preserves direction and shape but distorts • • A distance and area.A projection that preserves area,such as the 1111 Aerial Photography Albers equal-area conic projection,should be used if more • • A/D accurate calculations of distance or area are required. ^r B This product is generated from the USDA-NRCS certified data as .v B/D of the version date(s)listed below. • r C Soil Survey Area: Forsyth County, North Carolina Survey Area Data: Version 24,Sep 8,2022 • • C/D Soil map units are labeled(as space allows)for map scales • • D 1:50,000 or larger. • w Not rated or not available Date(s)aerial images were photographed: Oct 17,2020—Nov 3, Soil Rating Points 2020 p A The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background O A/D imagery displayed on these maps.As a result,some minor • B shifting of map unit boundaries may be evident. • B/D USDA Natural Resources Web Soil Survey 9/18/2023 Conservation Service National Cooperative Soil Survey Page 2 of 4 Hydrologic Soil Group—Forsyth County, North Carolina Hydrologic Soil Group Map unit symbol Map unit name Rating Acres in AOI Percent of AOI CmC2 Clifford clay loam,6 to B 1.3 1.5% 10 percent slopes, moderately eroded CoA Codorus loam,0 to 2 B/D 8.2 9.3% percent slopes, frequently flooded FcC2 Fairview clay loam,6 to C 6.3 7.1% 10 percent slopes, moderately eroded FcD2 Fairview clay loam, 10 C 2.5 2.9% to 15 percent slopes, moderately eroded PcF2 Pacolet clay loam, 15 to B 14.7 16.6% 45 percent slopes, moderately eroded PoF Poplar Forest fine sandy B 2.3 2.6% loam, 15 to 45 percent slopes SmD Siloam sandy loam, 10 D 0.0 0.0% to 15 percent slopes TmB Tomlin loam,2 to 6 B 18.2 20.6% percent slopes TmC Tomlin loam,6 to 10 B 0.2 0.2% percent slopes ToB2 Tomlin clay loam,2 to 6 B 11.5 12.9% percent slopes, moderately eroded ToC2 Tomlin clay loam,6 to B 14.9 16.9% 10 percent slopes, moderately eroded ToD2 Tomlin clay loam, 10 to B 8.4 9.4% 15 percent slopes, moderately eroded Totals for Area of Interest 88.7 100.0% usm Natural Resources Web Soil Survey 9/18/2023 Conservation Service National Cooperative Soil Survey Page 3 of 4 Hydrologic Soil Group—Forsyth County, North Carolina Description Hydrologic soil groups are based on estimates of runoff potential. Soils are assigned to one of four groups according to the rate of water infiltration when the soils are not protected by vegetation, are thoroughly wet, and receive precipitation from long-duration storms. The soils in the United States are assigned to four groups (A, B, C, and D) and three dual classes (A/D, B/D, and C/D). The groups are defined as follows: Group A. Soils having a high infiltration rate (low runoff potential)when thoroughly wet. These consist mainly of deep, well drained to excessively drained sands or gravelly sands. These soils have a high rate of water transmission. Group B. Soils having a moderate infiltration rate when thoroughly wet. These consist chiefly of moderately deep or deep, moderately well drained or well drained soils that have moderately fine texture to moderately coarse texture. These soils have a moderate rate of water transmission. Group C. Soils having a slow infiltration rate when thoroughly wet. These consist chiefly of soils having a layer that impedes the downward movement of water or soils of moderately fine texture or fine texture. These soils have a slow rate of water transmission. Group D. Soils having a very slow infiltration rate (high runoff potential)when thoroughly wet. These consist chiefly of clays that have a high shrink-swell potential, soils that have a high water table, soils that have a claypan or clay layer at or near the surface, and soils that are shallow over nearly impervious material. These soils have a very slow rate of water transmission. If a soil is assigned to a dual hydrologic group (A/D, B/D, or C/D), the first letter is for drained areas and the second is for undrained areas. Only the soils that in their natural condition are in group D are assigned to dual classes. Rating Options Aggregation Method: Dominant Condition Component Percent Cutoff.None Specified Tie-break Rule: Higher USDA Natural Resources Web Soil Survey 9/18/2023 Conservation Service National Cooperative Soil Survey Page 4 of 4