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HomeMy WebLinkAbout005_Civil Stormwater Design Report DESIGN REPORT STORMWATER MANAGEMENT COTTAGES AT BLACKWOOD GROVES SITE PLAN LOTS 1 & 2, BLOCK 10 AND LOTS 1 & 2, BLOCK 11 BLACKWOOD GROVES SUBDIVISION, PHASE 1 Prepared for: Blackwood Land Fund, LLC 140 Village Crossing Way, Unit 3B Bozeman, MT 59715 Prepared by: Project Number: 211217 November 2021 INTRODUCTION The Cottages at Blackwood Groves consists of 58 one-, two-, and three-bedroom dwelling units, located on Lots 1&2, Block 10 and Lots 1&2, Block 11 of Blackwood Groves Subdivision, Phase 1. As part of the Blackwood Groves Subdivision, Phase 1 Infrastructure design stormwater ponds were sized to detain portions of the runoff from the multi-family lots located on Blocks 10 and 11. Runoff generated beyond the allocated limit will be stored on each block in retention ponds. Supporting stormwater calculations are attached to this report. A Drainage Area Map is included in Appendix A. Calculations for each individual drainage area are included in Appendix B. Pond sizing calculations are included in Appendix C. Groundwater depth information is included in Appendix D. The Blackwood Groves, Phase 1 Stormwater Design Report is included in Appendix E. DRAINAGE AREAS Drainage Area 1 Drainage Area 1 consists of the western portion of Lot 1, Block 10. Drainage Area discharges into the subdivision R.O.W. and will be treated in the subdivision Detention Pond 9. Roof downspouts and swales between the buildings will convey the runoff to the R.O.W. Drainage Area 1 of the Cottages Site Plan corresponds to Drainage Area 9G of the Phase 1 Design Report (see Appendix E). Based on the Phase 1 design report, Lot 1, Block 10 was assigned a C value of C=0.6, which equates to a C*Area (Rational “C” factor multiplied by the drainage basin area) of 23,911 sf. The C*Area of Drainage Area 1 is 16,777, which is well below the allocated value for the lot. As such, the existing subdivision infrastructure has capacity to handle Drainage Area 1. Drainage Area 2 Drainage Area 2 consists of the largest portion of Block 10. Runoff from this drainage area will be retained in Retention Pond 1, located in the north portion of the site. This pond was sized to retain the 10-year, 2-hour storm. In addition to the 10-year, 2-hour storm the proposed retention ponds were sized to retain the runoff generated from the first 0.5” of rainfall, otherwise known as the Runoff Reduction Volume (RRV.). It was determined that the 10-year, 2-hour storm and RRV required 833 cubic feet of storage and 424 cubic feet of storage, respectively. Retention Pond 1 provided 993 cubic feet of storage. Drainage Area 3 Drainage Area 3 consists of the southern portion of Lots 1&2, Block 10. Drainage Area 3 discharges into the subdivision R.O.W. and will be treated in the subdivision Detention Pond 9. Drainage Area 3 of the Cottages Site Plan corresponds to Drainage Area 9D of the Phase 1 Design Report. Based on the Phase 1 design report, Lot 2, Block 10 was assigned a C value of C=0.4, which equates to a C*Area (Rational “C” factor multiplied by the drainage basin area) of 5,138 sf. The C*Area of Drainage Area 3 is 4,910, which is below the allocated value for the lot. As such, the existing subdivision infrastructure has capacity to handle Drainage Area 3. Drainage Area 4 Drainage Area 4 consists of the northern and eastern portions of Lot 2, Block 10. Drainage Area 4 discharges into the subdivision R.O.W. and will be treated in the subdivision Detention Pond 8C. Drainage Area 4 of the Cottages Site Plan corresponds to Drainage Area 8J of the Phase 1 Design Report. Based on the Phase 1 design report, Lot 2, Block 10 was assigned a C value of C=0.4, which equates to a C*Area (Rational “C” factor multiplied by the drainage basin area) of 9,561 sf. The C*Area of Drainage Area 3 is 9,455 sf, which is below the allocated value for the lot. As such, the existing subdivision infrastructure has capacity to handle Drainage Area 4. Drainage Area 5 Drainage Area 5 consists of a small portion of Lot 2, Block 10. Runoff from this drainage area will be retained in Retention Pond 4, located in the south portion of the site. This pond was sized to retain the 10-year, 2-hour storm and the RRV. It was determined that the 10-year, 2-hour storm and RRV required 211 cubic feet of storage and 110 cubic feet of storage, respectively. Retention Pond 4 provided 215 cubic feet of storage. Drainage Area 6 Drainage Area 6 consists of a small portion of Lot 2, Block 10. Runoff from this drainage area will be retained in Retention Pond 3, located in the eastern half of the site. This pond was sized to retain the 10-year, 2-hour storm and the RRV. It was determined that the 10-year, 2-hour storm and RRV required 220 cubic feet of storage and 127 cubic feet of storage, respectively. Retention Pond 3 provided 225 cubic feet of storage. Drainage Area 7 Drainage Area 7 consists of a small portion of Lot 2, Block 10. Runoff from this drainage area will be retained in Retention Pond 2, located in the central portion of the site. This pond was sized to retain the 10-year, 2-hour storm and the RRV. It was determined that the 10-year, 2-hour storm and RRV required 120 cubic feet of storage and 68 cubic feet of storage, respectively. Retention Pond 2 provided 125 cubic feet of storage. Drainage Area 8 Drainage Area 8 consists of the western portion of Lot 1, Block 11. Drainage Area discharges into the subdivision R.O.W. and will be treated in the subdivisions’ Detention Pond 8C. Drainage Area 8 of the Cottages Site Plan corresponds to Drainage Area 8L of the Phase 1 Design Report. Based on the Phase 1 design report, Lot 1, Block 11 was assigned a C value of C=0.4, which equates to a C*Area (Rational “C” factor multiplied by the drainage basin area) of 14,869 sf. The C*Area of Drainage Area 3 is 13,918 sf, which is below the allocated value for the lot. As such, the existing subdivision infrastructure has capacity to handle Drainage Area 8. Drainage Area 9 Drainage Area 9 consists of the largest portion of Block 11. Runoff from this drainage area will be retained in Retention Pond 6, located in the north portion of the block. This pond was sized to retain the 10-year, 2-hour storm and RRV. It was determined that the 10-year, 2-hour storm and RRV required 958 cubic feet of storage and 493 cubic feet of storage, respectively. Retention Pond 6 provided 1,404 cubic feet of storage. Drainage Area 10 Drainage Area 10 consists of the eastern portion of Lot 2, Block 11. Drainage Area discharges into the subdivision R.O.W. and will be treated in the subdivisions’ Detention Pond 8A. Drainage Area 10 of the Cottages Site Plan corresponds to Drainage Area 8A of the Phase 1 Design Report. Based on the Phase 1 design report, Lot 2, Block 11 was assigned a C value of C=0.4, which equates to a C*Area (Rational “C” factor multiplied by the drainage basin area) of 14,162 sf. The C*Area of Drainage Area 3 is 13,602 sf, which is below the allocated value for the lot. As such, the existing subdivision infrastructure has capacity to handle Drainage Area 10. Drainage Area 11 Drainage Area 11 consists of the southwest portion of Lot 1, Block 11. Runoff from this drainage area will be retained in Retention Pond 5, located in the southwest portion of the lot. This pond was sized to retain the 10-year, 2-hour storm and the RRV. It was determined that the 10-year, 2- hour storm and RRV required 268 cubic feet of storage and 137 cubic feet of storage, respectively. Retention Pond 5 provided 275 cubic feet of storage. Drainage Area 12 Drainage Area 12 consists of the southeast portion of Lot 2, Block 11. Runoff from this drainage area will be retained in Retention Pond 7, located in the southeast portion of the lot. This pond was sized to retain the 10-year, 2-hour storm and the RRV. It was determined that the 10-year, 2-hour storm and RRV required 392 cubic feet of storage and 204 cubic feet of storage, respectively. Retention Pond 7 provided 395 cubic feet of storage. Table 1: Pond Sizing Summary Pond Contributing Area (sf) Weighted C-Value Runoff Reduction Volume (cf) Required Retention Storage Volume (cf) Proposed Storage Volume (cf) 1 24,135 0.51 424 833 993 2 2,588 0.68 68 120 125 3 4,540 0.72 127 220 225 4 5,719 0.54 110 211 215 5 7,699 0.51 137 268 275 6 27,073 0.52 493 958 1,404 7 10,770 0.54 204 392 395 GROUNDWATER CONSIDERATIONS Groundwater monitoring wells were installed across the subject property in 2019 and were monitored throughout the spring/summer of 2019 and spring of 2020 during the subdivision preliminary plat process. The results generally showed that seasonal high groundwater (SHGW) peaked in early April, and ranged from 7” to 3.5’ below existing grade. This information was used to generate a SHGW elevation surface in AutoCAD to reference during the stormwater design for the subdivision. All proposed ponds in the development are set with the bottom of pond elevation above the SHGW elevation in the pond footprint. The proposed retention pond elevations and approximate SHGW elevations are listed in Table 3 below. The groundwater monitoring results can be found in Appendix D. Table 2: SHGW and Proposed Pond Elevations Pond Approximate Existing Surface Elevation (ft) Estimated Peak Groundwater Elevation (ft. bgs) Estimated Peak Groundwater Elevation (ft.) Proposed Pond Top Elevation (ft) Proposed Pond Bottom Elevation (ft.) 1 5006.5 1.0 5005.5 5007.03 5008.53 2 5006.5 1.2 5005.3 5008.74 5007.24 3 5007.7 1.5 5006.2 5008.90 5007.40 4 5008.5 1.6 5006.9 5010.00 5008.50 5 5008.5 2.8 5005.7 5009.90 5008.40 6 5004.8 0.9 5004.9 5005.86 5004.36 7 5006.3 1.5 5004.8 5000.65 4999.15 G:\C&H\21\211217\Design Reports\Storm\211217 Stormwater Design Report.Docx APPENDIX A DRAINAGE AREA MAP APPENDIX B DRAINAGE AREA CALCULATIONS DRAINAGE AREA #1 DRAINAGE AREA #1 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft2 )C * Area Hardscape 0.95 4424 4202 Roof 0.95 11072 10518 Landscape 0.20 10280 2056 Total 25776 16777 A = Area (acres)0.5917 C = Weighted C Factor 0.65 C* Area (ft 2 ) =16,777 Allocated C* Area (ft2 ) =23,911 (Drainage Area 9G)* *Blackwood Groves, Phase 1 Stormwater Design Report DRAINAGE AREA #2 DRAINAGE AREA #2 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2)C * Area Hardscape 0.95 2713 2577 Roof 0.95 7243 6881 Landscape 0.20 14180 2836 Total 24135 12294 A = Area (acres)0.5541 C = Weighted C Factor 0.51 DRAINAGE AREA #3 DRAINAGE AREA #3 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2)C * Area Hardscape 0.95 1458 1385 Roof 0.95 2521 2395 Landscape 0.20 5653 1131 Total 9631 4910 A = Area (acres)0.2211 C = Weighted C Factor 0.51 C* Area (ft 2 ) =4,910 Allocated C* Area (ft2 ) =5,138 (Drainage Area 9D)* *Blackwood Groves, Phase 1 Stormwater Design Report DRAINAGE AREA #4 DRAINAGE AREA #4 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2)C * Area Hardscape 0.95 2986 2837 Roof 0.95 5597 5317 Landscape 0.20 6508 1302 Total 15091 9455 A = Area (acres)0.3464 C = Weighted C Factor 0.63 C* Area (ft 2 ) =9,455 Allocated C* Area (ft2 ) =9,561 (Drainage Area 8J)* *Blackwood Groves, Phase 1 Stormwater Design Report DRAINAGE AREA #5 DRAINAGE AREA #5 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2)C * Area Hardscape 0.95 651 618 Roof 0.95 1974 1875 Landscape 0.20 3094 619 Total 5719 3112 A = Area (acres)0.1313 C = Weighted C Factor 0.54 DRAINAGE AREA #6 DRAINAGE AREA #6 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2)C * Area Hardscape 0.95 401 381 Roof 0.95 2726 2590 Landscape 0.20 1413 283 Total 4540 3253 A = Area (acres)0.1042 C = Weighted C Factor 0.72 DRAINAGE AREA #7 DRAINAGE AREA #7 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2)C * Area Hardscape 0.95 243 230 Roof 0.95 1422 1351 Landscape 0.20 923 185 Total 2588 1766 A = Area (acres)0.0594 C = Weighted C Factor 0.68 DRAINAGE AREA #8 DRAINAGE AREA #8 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2)C * Area Hardscape 0.95 3801 3611 Roof 0.95 9150 8692 Landscape 0.20 8077 1615 Total 21027 13918 A = Area (acres)0.4827 C = Weighted C Factor 0.66 C* Area (ft 2 ) =13,918 Allocated C* Area (ft2 ) =14,869 (Drainage Area 8L)* *Blackwood Groves, Phase 1 Stormwater Design Report DRAINAGE AREA #9 DRAINAGE AREA #9 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2)C * Area Hardscape 0.95 3086 2932 Roof 0.95 8551 8123 Landscape 0.20 15436 3087 Total 27073 14142 A = Area (acres)0.6215 C = Weighted C Factor 0.52 DRAINAGE AREA # 10 DRAINAGE AREA #10 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2)C * Area Hardscape 0.95 3697 3512 Roof 0.95 8992 8542 Landscape 0.20 7737 1547 Total 20425 13602 A = Area (acres)0.4689 C = Weighted C Factor 0.67 C* Area (ft 2 ) =13,602 Allocated C* Area (ft2 ) =14,162 (Drainage Area 8A)* *Blackwood Groves, Phase 1 Stormwater Design Report DRAINAGE AREA # 11 DRAINAGE AREA #11 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2)C * Area Hardscape 0.95 1188 1128 Roof 0.95 2035 1933 Landscape 0.20 4476 895 Total 7699 3957 A = Area (acres)0.1767 C = Weighted C Factor 0.51 DRAINAGE AREA # 12 DRAINAGE AREA #12 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2)C * Area Hardscape 0.95 1493 1418 Roof 0.95 3351 3183 Landscape 0.20 5926 1185 Total 10770 5787 A = Area (acres)0.2472 C = Weighted C Factor 0.54 APPENDIX C POND SIZING CALCULATIONS RETENTION POND 1 REQUIRED VOLUME 1. Calculate Area and Weighted C Factor (Post-Development) Contributing Area C Area (ft 2 )C * Area Hardscape 0.95 2713 2577 Roof 0.95 7243 6881 Landscape 0.2 14180 2836 Total 24135 12294 A = Area (acres)0.5541 C = Weighted C Factor 0.51 2. Calculate Required Volume Q = CIA V=7200Q C = Weighted C Factor 0.51 I = intensity (in/hr) 0.41 (10 yr, 2hr storm) A = Area (acres)0.55 Q = runoff (cfs)0.12 V = REQUIRED VOL (ft3)833 PROVIDED VOL (ft3)993 Check the half inch requirement (per DSSP II.A.4) 3. Determine Area of Hardscape within Drainage Area #2 Contributing Area Area (ft 2 ) Hardscape 9,956 4. Calculate 1/2" runoff volume over hardscape (aka Runoff Reduction Volume [RRV] as calculated in Montana Post- Construction Storwater BMP Manual - Equation 3-1) RRV = [P*Rv*A]/12 P = Water quality rainfall depth 0.50 inches Rv = Dimensionless runoff coefficient 0.42 0.05 + 0.9*I I = Percent impervious cover (decimal)0.41 decimal A = Entire drainage area 0.55 acres RRV = Runoff Reduction Volume 0.010 acre-ft RRV = Runoff Reduction Volume 424 cubic feet Because the runoff volume from the 10-yr, 2-hr storm (for flood control) is greater than the runoff volume produced by the half inch rainfall (for water quality) the retention facility is sized to handle the larger volume (740 cf). RETENTION POND 2 REQUIRED VOLUME 1. Calculate Area and Weighted C Factor (Post-Development) Contributing Area C Area (ft 2)C * Area Hardscape 0.95 243 230 Roof 0.95 1422 1351 Landscape 0.2 923 185 Total 2588 1766 A = Area (acres)0.0594 C = Weighted C Factor 0.68 2. Calculate Required Volume Q = CIA V=7200Q C = Weighted C Factor 0.68 I = intensity (in/hr) 0.41 (10 yr, 2hr storm) A = Area (acres)0.06 Q = runoff (cfs)0.02 V = REQUIRED VOL (ft3)120 PROVIDED VOL (ft3)125 Check the half inch requirement (per DSSP II.A.4) 3. Determine Area of Hardscape within Drainage Area #7 Contributing Area Area (ft 2 ) Hardscape 1,665 4. Calculate 1/2" runoff volume over hardscape (aka Runoff Reduction Volume [RRV] as calculated in Montana Post- Construction Storwater BMP Manual - Equation 3-1) RRV = [P*Rv*A]/12 P = Water quality rainfall depth 0.50 inches Rv = Dimensionless runoff coefficient 0.63 0.05 + 0.9*I I = Percent impervious cover (decimal)0.64 decimal A = Entire drainage area 0.06 acres RRV = Runoff Reduction Volume 0.002 acre-ft RRV = Runoff Reduction Volume 68 cubic feet Because the runoff volume from the 10-yr, 2-hr storm (for flood control) is greater than the runoff volume produced by the half inch rainfall (for water quality) the retention facility is sized to handle the larger volume (120 cf). RETENTION POND 3 REQUIRED VOLUME 1. Calculate Area and Weighted C Factor (Post-Development) Contributing Area C Area (ft 2)C * Area Hardscape 0.95 401 381 Roof 0.95 2726 2590 Landscape 0.2 1413 283 Total 4540 3253 A = Area (acres)0.1042 C = Weighted C Factor 0.72 2. Calculate Required Volume Q = CIA V=7200Q C = Weighted C Factor 0.72 I = intensity (in/hr) 0.41 (10 yr, 2hr storm) A = Area (acres)0.10 Q = runoff (cfs)0.03 V = REQUIRED VOL (ft3)220 PROVIDED VOL (ft3)225 Check the half inch requirement (per DSSP II.A.4) 3. Determine Area of Hardscape within Drainage Area #6 Contributing Area Area (ft 2 ) Hardscape 3,127 4. Calculate 1/2" runoff volume over hardscape (aka Runoff Reduction Volume [RRV] as calculated in Montana Post- Construction Storwater BMP Manual - Equation 3-1) RRV = [P*Rv*A]/12 P = Water quality rainfall depth 0.50 inches Rv = Dimensionless runoff coefficient 0.67 0.05 + 0.9*I I = Percent impervious cover (decimal)0.69 decimal A = Entire drainage area 0.10 acres RRV = Runoff Reduction Volume 0.003 acre-ft RRV = Runoff Reduction Volume 127 cubic feet Because the runoff volume from the 10-yr, 2-hr storm (for flood control) is greater than the runoff volume produced by the half inch rainfall (for water quality) the retention facility is sized to handle the larger volume (220 cf). RETENTION POND 4 REQUIRED VOLUME 1. Calculate Area and Weighted C Factor (Post-Development) Contributing Area C Area (ft2 )C * Area Hardscape 0.95 651 618 Roof 0.95 1974 1875 Landscape 0.2 3094 619 Total 5719 3112 A = Area (acres)0.1313 C = Weighted C Factor 0.54 2. Calculate Required Volume Q = CIA V=7200Q C = Weighted C Factor 0.54 I = intensity (in/hr) 0.41 (10 yr, 2hr storm) A = Area (acres)0.13 Q = runoff (cfs)0.03 V = REQUIRED VOL (ft3)211 PROVIDED VOL (ft3)215 Check the half inch requirement (per DSSP II.A.4) 3. Determine Area of Hardscape within Drainage Area #5 Contributing Area Area (ft 2) Hardscape 2,624 4. Calculate 1/2" runoff volume over hardscape (aka Runoff Reduction Volume [RRV] as calculated in Montana Post- Construction Storwater BMP Manual - Equation 3-1) RRV = [P*Rv*A]/12 P = Water quality rainfall depth 0.50 inches Rv = Dimensionless runoff coefficient 0.46 0.05 + 0.9*I I = Percent impervious cover (decimal)0.46 decimal A = Entire drainage area 0.13 acres RRV = Runoff Reduction Volume 0.003 acre-ft RRV = Runoff Reduction Volume 110 cubic feet Because the runoff volume from the 10-yr, 2-hr storm (for flood control) is greater than the runoff volume produced by the half inch rainfall (for water quality) the retention facility is sized to handle the larger volume (211 cf). RETENTION POND 5 REQUIRED VOLUME 1. Calculate Area and Weighted C Factor (Post-Development) Contributing Area C Area (ft2 )C * Area Hardscape 0.95 1188 1128 Roof 0.95 2035 1933 Landscape 0.2 4476 895 Total 7699 3957 A = Area (acres)0.1767 C = Weighted C Factor 0.51 2. Calculate Required Volume Q = CIA V=7200Q C = Weighted C Factor 0.51 I = intensity (in/hr) 0.41 (10 yr, 2hr storm) A = Area (acres)0.18 Q = runoff (cfs)0.04 V = REQUIRED VOL (ft3)268 PROVIDED VOL (ft3)275 Check the half inch requirement (per DSSP II.A.4) 3. Determine Area of Hardscape within Drainage Area #11 Contributing Area Area (ft 2 ) Hardscape 3,223 4. Calculate 1/2" runoff volume over hardscape (aka Runoff Reduction Volume [RRV] as calculated in Montana Post- Construction Storwater BMP Manual - Equation 3-1) RRV = [P*Rv*A]/12 P = Water quality rainfall depth 0.50 inches Rv = Dimensionless runoff coefficient 0.43 0.05 + 0.9*I I = Percent impervious cover (decimal)0.42 decimal A = Entire drainage area 0.18 acres RRV = Runoff Reduction Volume 0.003 acre-ft RRV = Runoff Reduction Volume 137 cubic feet Because the runoff volume from the 10-yr, 2-hr storm (for flood control) is greater than the runoff volume produced by the half inch rainfall (for water quality) the retention facility is sized to handle the larger volume (256 cf). RETENTION POND 6 REQUIRED VOLUME 1. Calculate Area and Weighted C Factor (Post-Development) Contributing Area C Area (ft 2 )C * Area Hardscape 0.95 3086 2932 Roof 0.95 8551 8123 Landscape 0.2 15436 3087 Total 27073 14142 A = Area (acres)0.6215 C = Weighted C Factor 0.52 2. Calculate Required Volume Q = CIA V=7200Q C = Weighted C Factor 0.52 I = intensity (in/hr) 0.41 (10 yr, 2hr storm) A = Area (acres)0.62 Q = runoff (cfs)0.13 V = REQUIRED VOL (ft3)958 PROVIDED VOL (ft3)1404 Check the half inch requirement (per DSSP II.A.4) 3. Determine Area of Hardscape within Drainage Area #9 Contributing Area Area (ft2 ) Hardscape 11,637 4. Calculate 1/2" runoff volume over hardscape (aka Runoff Reduction Volume [RRV] as calculated in Montana Post- Construction Storwater BMP Manual - Equation 3-1) RRV = [P*Rv*A]/12 P = Water quality rainfall depth 0.50 inches Rv = Dimensionless runoff coefficient 0.44 0.05 + 0.9*I I = Percent impervious cover (decimal)0.43 decimal A = Entire drainage area 0.62 acres RRV = Runoff Reduction Volume 0.011 acre-ft RRV = Runoff Reduction Volume 493 cubic feet Because the runoff volume from the 10-yr, 2-hr storm (for flood control) is greater than the runoff volume produced by the half inch rainfall (for water quality) the retention facility is sized to handle the larger volume (967 cf). RETENTION POND 7 REQUIRED VOLUME 1. Calculate Area and Weighted C Factor (Post-Development) Contributing Area C Area (ft 2 )C * Area Hardscape 0.95 1493 1418 Roof 0.95 3351 3183 Landscape 0.2 5926 1185 Total 10770 5787 A = Area (acres)0.2472 C = Weighted C Factor 0.54 2. Calculate Required Volume Q = CIA V=7200Q C = Weighted C Factor 0.54 I = intensity (in/hr) 0.41 (10 yr, 2hr storm) A = Area (acres)0.25 Q = runoff (cfs)0.05 V = REQUIRED VOL (ft3)392 PROVIDED VOL (ft3)395 Check the half inch requirement (per DSSP II.A.4) 3. Determine Area of Hardscape within Drainage Area #12 Contributing Area Area (ft2 ) Hardscape 4,844 4. Calculate 1/2" runoff volume over hardscape (aka Runoff Reduction Volume [RRV] as calculated in Montana Post- Construction Storwater BMP Manual - Equation 3-1) RRV = [P*Rv*A]/12 P = Water quality rainfall depth 0.50 inches Rv = Dimensionless runoff coefficient 0.45 0.05 + 0.9*I I = Percent impervious cover (decimal)0.45 decimal A = Entire drainage area 0.25 acres RRV = Runoff Reduction Volume 0.005 acre-ft RRV = Runoff Reduction Volume 204 cubic feet Because the runoff volume from the 10-yr, 2-hr storm (for flood control) is greater than the runoff volume produced by the half inch rainfall (for water quality) the retention facility is sized to handle the larger volume (384 cf). APPENDIX D GROUNDWATER DEPTH INFORMATION Project Engineer: Project: South Bozeman, Gallatin County, MT Well Information:bgs = below ground surface ags = above ground surface MW-1 MW-2 MW-3 MW-4 MW-5 MW-6 MW-7 MW-8 MW-9 MW-10 MW-11 MW-12 MW-13 MW-14 MW-15 MW-16 MW-17 MW-18 MW-19 MW-20 3.83 3.00 3.08 3.67 1.50 2.42 2.08 3.58 2.92 2.92 3.83 2.92 3.92 3.58 4.08 3.00 3.92 3.50 3.58 2.92 Groundwater Information: MW-1 MW-2 MW-3 MW-4 MW-5 MW-6 MW-7 MW-8 MW-9 MW-10 MW-11 MW-12 MW-13 MW-14 MW-15 MW-16 MW-17 MW-18 MW-19 MW-20 3.34 3.05 3.02 2.78 3.45 1.58 4.24 4.27 2.55 4.13 3.99 4.36 2.25 2.27 2.26 5.50 2.71 2.20 2.97 2.38 3.47 3.18 3.11 2.85 3.49 1.50 4.42 4.42 2.64 4.34 4.31 4.78 2.50 2.32 2.60 6.10 2.85 2.42 3.40 2.77 3.57 3.23 3.13 2.94 4.10 1.64 4.53 4.53 2.67 4.45 4.36 4.90 2.54 2.39 2.65 6.21 2.92 2.74 3.74 2.96 3.75 3.42 3.26 3.18 3.74 1.88 4.72 4.70 2.80 4.59 4.50 5.16 2.84 2.54 2.84 6.32 3.18 3.14 4.07 3.19 3.78 3.63 3.36 3.35 3.81 1.94 4.90 4.98 2.99 4.86 4.56 5.31 3.16 2.83 3.23 DRY 3.79 3.68 4.31 3.49 3.76 3.65 3.41 3.43 3.76 1.91 4.94 5.11 3.09 4.98 4.68 5.48 3.25 2.79 3.30 DRY 4.17 3.91 4.51 3.56 3.94 3.82 3.52 3.45 3.83 2.00 4.90 5.23 3.27 5.08 4.82 5.60 3.42 2.88 3.37 DRY 4.29 4.05 4.67 3.59 3.90 3.68 3.38 3.31 3.75 1.94 4.85 4.93 3.08 5.02 4.86 5.66 3.37 2.88 3.20 DRY 4.22 4.11 4.80 3.48 4.00 3.87 3.55 3.60 4.01 2.24 5.11 5.23 3.44 5.18 4.82 5.65 3.54 3.13 3.46 DRY 4.59 4.31 4.87 3.80 4.09 3.52 3.34 3.33 3.81 2.09 5.06 5.03 3.11 4.99 5.42 5.08 3.34 2.89 3.37 DRY 4.59 4.41 4.47 3.60 4.14 4.09 3.69 3.72 3.92 2.34 5.24 5.42 3.69 5.39 4.95 5.78 3.73 3.34 3.69 DRY 4.87 4.65 5.03 3.89 4.16 4.38 4.13 4.01 4.12 2.49 5.43 5.70 4.06 5.99 5.27 6.24 4.20 3.79 3.99 DRY 5.29 5.19 5.63 4.07 ICE 2.50 2.49 2.03 ICE 0.93 3.43 3.60 2.39 ICE 3.69 3.88 1.38 1.47 1.82 4.04 2.27 0.96 2.07 2.01 1.99 1.95 2.16 1.64 3.00 0.63 3.04 3.29 2.19 3.08 3.07 3.33 0.72 0.72 0.87 3.57 2.10 0.60 1.67 1.28 2.65 2.25 2.37 1.93 3.35 1.03 3.14 3.47 2.29 3.26 3.29 3.60 1.18 1.62 1.57 3.60 2.30 1.20 2.19 1.45 2.94 2.50 2.53 2.17 1.90 1.54 3.32 3.68 2.33 3.53 3.63 3.83 1.56 1.53 1.86 4.13 2.40 1.45 2.47 1.86 3.27 2.97 2.84 2.64 2.35 1.42 3.72 4.30 2.48 3.95 3.92 4.23 2.00 1.67 2.13 4.52 2.68 2.04 3.07 2.38 3.47 3.20 3.00 2.85 2.50 1.52 3.94 4.38 2.59 4.23 4.17 4.61 2.30 2.29 2.42 4.97 2.81 2.55 3.42 2.70 3.57 3.28 3.10 2.98 2.60 1.68 4.13 4.52 2.65 4.39 4.37 4.88 2.53 2.35 2.64 DRY 2.91 2.92 3.85 2.93 3.68 3.38 3.21 3.10 2.70 1.74 4.29 4.68 2.70 4.54 4.57 5.10 2.73 2.43 2.81 DRY 3.12 3.30 4.13 3.17 3.79 3.51 3.32 3.20 2.66 1.89 4.51 4.79 2.81 4.71 4.74 5.32 2.93 2.60 2.97 DRY 3.47 3.56 4.37 3.33 3.92 3.63 3.51 3.38 2.79 1.95 4.79 4.90 2.92 4.89 4.78 5.49 3.08 2.63 3.08 DRY 3.73 4.09 4.57 3.59 5.15.20 4.10.20 4.17.20 4.24.20 5.1.20 5.8.20 Well ID Well Depth (feet-bgs) Top of Well (feet-ags) Ground Elevation 4.6.20 Date 5.10.19 6.10.19 6.17.19 6.20.19 6.28.19 7.12.19 7.26.19 8.9.19 Monitor Well Data Depth to Ground Water (feet-bgs) Project Number: 190390 South Bozeman Groundwater Monitoring Project Location: 8.23.19 3.24.20 5.20.19 5.24.19 5.31.19 5.22.205.29.20 APPENDIX E BLACKWOOD GROVES SUBDIVISION PHASE 1 STORMWATER DESIGN REPORT BLACKWOOD GROVES SUBDIVISION, PHASE 1 STORMWATER DESIGN REPORT Prepared for: Bridger Builders, Inc. 115 West Kagy Boulevard Bozeman, MT 59715 Prepared by: Project Number: 190390 July 29, 2021 BLACKWOOD GROVES SUBDIVISION – STORMWATER DESIGN REPORT July 29, 2021 #190390 1 TABLE OF CONTENTS REPORT Introduction ..........................................................................................................................2 Existing Site Conditions ......................................................................................................2 Pre-Development Drainage Areas .......................................................................................2 Storm Sewer Facilities Design .............................................................................................3 Post-Development Drainage Areas ......................................................................................4 Stormwater Pond Design .....................................................................................................6 Groundwater Considerations ...............................................................................................8 APPENDICES Appendix A: Drainage Area Maps Appendix B: Pre-Development Drainage Area Calculations Appendix C: Post-Development Drainage Area Calculations Appendix D: Pond Sizing Calculations Appendix E: Groundwater Monitoring Data BLACKWOOD GROVES SUBDIVISION – STORMWATER DESIGN REPORT July 29, 2021 #190390 2 INTRODUCTION The Blackwood Groves Subdivision is a proposed 120-acre development located at the south side of the City of Bozeman. The proposed project is zoned as Residential Emphasis Mixed Use (REMU) and will feature a variety of commercial, residential, and park/open space developments. As part of the project, public improvements, including water, sanitary sewer, stormwater, and City road infrastructure are proposed. This report is intended to evaluate the drainage design for Phase 1 of the development. EXISTING SITE CONDITIONS The existing property is currently vacant and is being used for agricultural purposes. The property is bounded by S. 19th Avenue to the west, vacant agricultural land and Alder Creek Subdivision to the north, Sacajawea Middle School to the east, and vacant agricultural land to the south. The property generally slopes from south to north at 1%-2%. Several agricultural irrigation ditches, and watercourses cross the property. Based on site topography, stormwater runoff on the existing site currently drains to 4 of these water features that cross the property via overland sheet flow. A large portion of the approximately 119-acre agricultural property to the south of the project also sheet flows onto the project site, draining to these same 4 water features. PRE-DEVELOPMENT DRAINAGE AREAS Stormwater runoff from the proposed site improvements will primarily be controlled and treated through the use of several proposed detention ponds that will release runoff into these 4 water features. These detention ponds will discharge runoff into these water features at the pre- development runoff rates that currently contribute to these water features from the existing site. In order to determine the pre-development runoff rates, pre-development drainage areas were delineated for each water feature on the subject property. These drainage areas are shown on the “Pre-Development Drainage Area Plan” in Appendix A. City of Bozeman GIS contours were used in order to determine the portion of the property to the south of the site that sheet flows onto the subject property. These contours are shown in yellow on the Pre-Development Drainage Area Plan. As shown by the slight overlap of these GIS BLACKWOOD GROVES SUBDIVISION – STORMWATER DESIGN REPORT July 29, 2021 #190390 3 contours with the contours produced from the topographic survey that C&H Engineering performed of the project site, these GIS contours match extremely well with the contours from the survey. EX DA #1 accounts for runoff from the subject property that currently drains to the irrigation ditch located along the east side of the S. 19th Avenue right-of-way, labeled “Irrigation Ditch – West” for the purposes of this report. EX DA #2 accounts for runoff draining to the irrigation ditch running east/west along the north property boundary, labeled “Irrigation Ditch – North” for the purposes of this report. This drainage area also collects runoff from a large portion of the property to the south of the project site. EX DA #3 accounts for runoff contributing to the irrigation ditch located at the eastern side of the property that continues through Alder Creek Subdivision to the north. This ditch is labeled as “Irrigation Ditch – Center” for the purposes of this report. The final drainage area, EX DA #4, accounts for runoff from the far eastern portion of the site that drains to the two watercourses that converge and drain north into the park in Alder Creek Subdivision. These watercourses are labeled as “Unnamed Watercourse – Center” and “Unnamed Watercourse – East” for the purposes of this report. This drainage area also collects runoff from a portion of the property to the south of the project site. Calculations for the time of concentration, and pre-development runoff rates for these drainage areas can be found in Appendix B. STORM SEWER FACILITIES DESIGN Stormwater runoff from the proposed improvements will be conveyed via curb and gutter channel flow to a series of curb chases and storm sewer inlets. It will then be routed through storm drainage pipes to detention and retention ponds for storage. The detention ponds will release runoff at pre-development runoff rates into 4 of the irrigation ditches and watercourses that flow through the property. Pre and Post development Drainage Area Maps are included in Appendix A, and calculations for pond sizing for each of the post development drainage areas (total area, weighted C factor, required and provided storage volumes, and discharge rates) are included in Appendix C. BLACKWOOD GROVES SUBDIVISION – STORMWATER DESIGN REPORT July 29, 2021 #190390 4 Storm sewer facilities were sized for the 25-yr storm using Manning’s Equation, and for each inlet, the contributing area, gutter capacity, weighted C factor, and time of concentration were calculated. These values were input into Manning’s Equation to check capacity and flow characteristics for inlets, storm drain pipes, and curb gutters. All curb gutters were designed to maintain 0.15’ freeboard per C.O.B. Design Manual Section IV.C.5. POST-DEVELOPMENT DRAINAGE AREAS This phase of the project was divided into 7 drainage areas based on the retention or detention ponds that these areas will eventually drain to. These drainage areas are further divided based on the proposed use within each area. This stormwater design conservatively assumes that 100% of the runoff from the multifamily and commercial lots will drain to these common stormwater ponds, and that no stormwater storage or treatment will take place on the individual lots. Phase 1 consists of Drainage Areas 6-9, and a small portion of Drainage Area 5. Each area type was assigned a C-value based on the proposed use. Several of these C-values (i.e. open land, and low/medium density residential) were taken from Table I-1 in the City of Bozeman Design Standards and Specifications, while the remainder were calculated based on the impervious and landscaped cover ratios anticipated in each area. The C-value for each right-of- way type (local, collector, alley, angled-parking) were calculated based on the ratio of impervious to landscaped area of the standard cross-section of these right-of-ways. The dense residential C-value for the lots that are proposed for multi-family developments was calculated by reviewing the impervious/landscaped ratios for the proposed layouts for several of these lots, and averaging the C-values. This produced a C-value of 0.75, which is more conservative than the dense residential value of 0.50 from Table I-1 in the city standards. Several of the dense residential lots have the space to provide onsite stormwater management. Therefore, these lots located in Drainage Area 8 and a portion of Drainage Area 9 (DA #9C) have been assigned a reduced C-value of 0.40. The C-value for the several commercial blocks that are intended to be the development’s “town center” was conservatively assumed to be 0.95, or completely impervious. The proposed commercial lots in Block 1 and Block 13 were assigned BLACKWOOD GROVES SUBDIVISION – STORMWATER DESIGN REPORT July 29, 2021 #190390 5 the same C-value as the dense residential lots (0.75) since they are not intended to be developed as densely as the town center lots. This C-value of 0.75 is more conservative than the commercial neighborhood C-value of 0.60 from Table I-1 in the city standards. The C-values for each area type are provided in the following table: Table 1: C-Values Area Type C-Value ROW – Local 0.76 ROW – Collector 0.70 ROW – Alley 0.80 ROW – Angled 0.93 Residential – Low/Med 0.35 Residential - Dense 0.75 Residential –Dense (Reduced C) 0.40 Commercial 0.95 Open Space 0.20 Park 0.20 The extents of the post development drainage areas can be seen on the drainage area map included in Appendix A. It should be noted that only the Spring Ridge Drive portion of Drainage Area 5 will be installed with this phase of the project. Similarly, only the South 11th Avenue portion of Drainage Areas 6 & 7 will be installed with this phase. The proposed drainage area map further subdivides the drainage areas (9A, 9B, 9C etc.) based on which inlet they are draining to. In addition, time of concentration flow paths for each sub-area are depicted on the proposed drainage area map. It should be noted that overland flow from the right-of-way line to the curb flow line used a composite C value of 0.50 in the time of concentration calculations. The C value was based on a ratio of the landscape boulevard to hardscape sidewalk. Curb inlets were spaced to provide adequate gutter flow capacity without encroaching more than 0.15-feet of freeboard per C.O.B. Design Manual Section IV.C.5. Calculations showing the peak runoff value BLACKWOOD GROVES SUBDIVISION – STORMWATER DESIGN REPORT July 29, 2021 #190390 6 as well as the determined gutter capacity for the sub-areas are included in Appendix C. Additionally, storm sewer pipes were sized to accommodate the 25-year storm flows. Pipe capacity calculations are included in Appendix C. Building design guidelines, enforced by the Property Owners Association, will include a requirement, enforced in the covenants, for each individual lot owner to route their roof drainage to rain barrels or on-site infiltration facilities, or to surface drain the runoff to the front side of the lot where it will collect in the street. The site will be graded to make this feasible for each lot. The proposed detention and retention facilities are sized to accommodate any and all lots that route their roof runoff to the street; any lots utilizing on-site runoff storage will result in excess storage capacity, and improved storm water treatment. STORMWATER POND DESIGN Detention Ponds 6-9 have been sized according to City of Bozeman Design Standards. In accordance with the design standards the ponds were sized to retain the runoff generated from the first 0.5” of rainfall, otherwise known as the Runoff Reduction Volume (RRV.). The detention ponds are also sized to limit discharge to pre-development rates for the 10-year storm event, while the retention pond is designed to store the runoff volume of the 10-year storm event. Each pond has been designed with 4:1 side slopes and a max water storage depth of 1.5’. The detention ponds have also been designed with outlet structures containing a slotted weir to control the discharge rate from the ponds. In an effort to accommodate the RRV from each drainage basin, the inlet into the outlet structures has been raised to allow for stormwater retention prior to discharge. The portions of Block 12 and Block 17 draining to Detention Pond 8B will have to retain the RRV on their individual lots prior to discharging into the public system, The RRV for the remainder all commercial and multi-family lots can be handled by the proposed detention ponds. Calculations used for sizing each pond can be found in Appendix D. Pond storage capacities were calculated using volume surfaces in AutoCAD Civil 3D. BLACKWOOD GROVES SUBDIVISION – STORMWATER DESIGN REPORT July 29, 2021 #190390 7 As stated previously, a small portion of the Drainage Area 5 will be installed with this phase of the subdivision. There are two inlets that will discharge into Detention Pond 5 being installed with this Phase 1. In order to manage the runoff from this area, a temporary retention pond will be installed in the location of future Detention Pond #5. Pond sizing calculations can be found in Appendix D. The proposed design has several detention ponds that discharge to the same water feature / pre- development drainage area. Where this occurs, the pre-development runoff rate was divided amongst each of the contributing detention ponds, so that their total discharge rate does not exceed the pre-development runoff rate for that drainage area / water feature. The pre- development runoff rate from EX DA #2 draining into “Irrigation Ditch - North” was calculated to be 8.73 cfs. Proposed Detention Pond #9 will discharge into “Irrigation Ditch – West”. It was assumed that because the northern and western irrigation ditches rejoin north of the project area, the same shared release rate calculated for EX DA #2 can be applied to detention ponds 8A, 8B, 8C and 9. Therefore, the combined discharge rates from each of these detention ponds totals 8.73 cfs. Similarly Ponds 6 & 7 share a pre-development runoff rate generated from EX DA #4. There are ponds to be installed with future phases that will also share this runoff rate. As such, the leftover difference from Phase 1 can be applied to these future phases. The pre-development conditions for each detention pond are included in the pond sizing calculations in Appendix C. A summary of the pond sizing calculations can be found in Table 2 below. Table 2: Pond Sizing Summary Pond Storage type Pre Development Drainage Area Contributing Area (acre) Weighted C-Value Runoff Reduction Volume (cf) Required Detention Storage Volume (cf) Proposed Storage Volume (cf) 5 Retention - 0.62 0.76 810 1,118 1,992 6 Detention EX 4 3.68 0.72 4,494 4,669 4,777 7 Detention EX 4 8.04 0.71 11,699 12,218 12,484 8A Detention EX 2 7.60 0.55 4,586 5,028 5,130 8B Detention EX 2 9.56 0.58 5,061 5,094 5,098 8C Detention EX 2 5.77 0.47 3,903 2,733 3,925 9 Detention EX 2 22.53 0.67 25,002 55,563 57,340 A Retention - 0.16 0.76 205 351 BLACKWOOD GROVES SUBDIVISION – STORMWATER DESIGN REPORT July 29, 2021 #190390 8 Due to grading limitations curb inlets could not be set on the northern property boundaries to capture all drainage from the site. In an effort to retain the maximum practicable amount of runoff curb chases are proposed to pick up additional runoff. There is approximately 6,000 sf of local street R.O.W. in Spring Ridge Drive and South 15th Avenue that will drain into the retention pond located at the NW corner of the Alder Creek Subdivision. The new development will generate an additional extra 618 cf of runoff into this pond. Based on review of the previous design report there is approximately 1,644 cf of excess capacity in the 26,000 cf existing retention pond. A small portion of South 11th will drain into the detention pond located in the Alder Creek Phase 3 park. It is expected to generate and additional 255 cf of runoff to the detention pond. There are 322 cf of excess capacity in the 4,175 cf existing detention pond. As such, it is anticipated that the facilities in the Alder Creek Subdivision have sufficient capacity to handle the small amount of excess runoff from the proposed development. GROUNDWATER CONSIDERATIONS Groundwater monitoring wells were installed across the subject property in 2019 and were monitored throughout the spring/summer of 2019 and spring of 2020. The results generally showed that seasonal high groundwater (SHGW) peaked in early April, and ranged from 7” to 3.5’ below existing grade. This information was used to generate a SHGW elevation surface in AutoCAD to reference during the stormwater design for the subdivision. Additional measurements along the northern property boundary were taken in the spring of 2021 to refine the SHGW surface in that area. All proposed ponds in the development are set with the bottom of pond elevation above the SHGW elevation in the pond footprint. The Phase 1 pond elevations and approximate SHGW elevations are listed in Table 3 below. The groundwater monitoring results can be found in Appendix D. BLACKWOOD GROVES SUBDIVISION – STORMWATER DESIGN REPORT July 29, 2021 #190390 9 Table 3: SHGW and Proposed Pond Elevations Pond Storage type Approximate Existing Surface Elevation (ft) Estimated Peak Groundwater Elevation (ft. bgs) Estimated Peak Groundwater Elevation (ft.) Proposed Pond Top Elevation (ft) Proposed Pond Bottom Elevation (ft.) 5 Retention 5005.4 2.91 5002.50 5005.00 5003.50 6 Detention 5000.6 4.16 5000.26 5002.05 5000.55 7 Detention 4997.2 1.95 4995.29 4997.00 4995.50 8A Detention 4999.3 1.15 4998.15 4999.75 4998.25 8B Detention 4999.3 1.15 4998.15 4999.75 4998.25 8C Detention 5000.8 1.67 4999.13 5000.65 4999.15 9 Detention 5000.9 1.42 4999.48 5001.21 4999.71 A Retention 5000.5 1.42 4999.08 5001.00 4999.50 APPENDIX A Drainage Area Maps APPENDIX B Pre-Development Drainage Area Calculations DA - EX 1 REQUIRED VOLUME 1. Calculate Area and Weighted C Factor (Post-Development) Contributing Area DA C Area (ft2 )C * Area Open Land EX 1 0.20 339691 67938 Total 339691 67938 A = Area (acres)7.80 Storm C = Weighted C Factor 0.20 Return (yrs)Cf 2 to 10 1 2. Calculate T c (Pre-Development)11 to 25 1.1 Tc Overland Flow 26 to 50 1.2 Tc = 1.87 (1.1-CCf)D1/2/S1/3 51 to 100 1.25 S = Slope of Basin (%)1.460 C = Rational Method Runoff Coefficient 0.2 Cf = Frequency Adjustment Factor 1 D = Length of Basin (ft)1773 Tc (Pre-Development) (minutes)62 3. Calculate Rainfall Intensity (Duration = Pre-Development Tc) i = 0.64x-0.65 (10-yr Storm, Fig. I-3, COB Design Standards) x = storm duration (hrs)1.04 (Tc Pre-Development) i = rainfall intensity (in./hr.)0.62 4. Calculate Runoff Rate (Pre-Development) Q = CiA C = Rational Method Runoff Coefficient 0.2 (open land) i = rainfall intensity (in./hr.)0.62 (calculated above) A = Area (acres)7.80 (calculated above) Q = Runoff Rate (Pre-Development) (cfs)0.97 DA - EX 2 REQUIRED VOLUME 1. Calculate Area and Weighted C Factor (Post-Development) Contributing Area DA C Area (ft2 )C * Area Open Land EX 2 0.20 4033738 806748 Total 4033738 806748 A = Area (acres)92.60 Storm C = Weighted C Factor 0.20 Return (yrs)Cf 2 to 10 1 2. Calculate T c (Pre-Development)11 to 25 1.1 Tc Overland Flow 26 to 50 1.2 Tc = 1.87 (1.1-CCf)D1/2/S1/3 51 to 100 1.25 S = Slope of Basin (%)1.490 C = Rational Method Runoff Coefficient 0.2 Cf = Frequency Adjustment Factor 1 D = Length of Basin (ft)4250 Tc (Pre-Development) (minutes)96 3. Calculate Rainfall Intensity (Duration = Pre-Development Tc) i = 0.64x-0.65 (10-yr Storm, Fig. I-3, COB Design Standards) x = storm duration (hrs)1.60 (Tc Pre-Development) i = rainfall intensity (in./hr.)0.47 4. Calculate Runoff Rate (Pre-Development) Q = CiA C = Rational Method Runoff Coefficient 0.2 (open land) i = rainfall intensity (in./hr.)0.47 (calculated above) A = Area (acres)92.60 (calculated above) Q = Runoff Rate (Pre-Development) (cfs)8.73 DA - EX 3 REQUIRED VOLUME 1. Calculate Area and Weighted C Factor (Post-Development) Contributing Area DA C Area (ft2 )C * Area Open Land EX 3 0.20 238679 47736 Total 238679 47736 A = Area (acres)5.48 Storm C = Weighted C Factor 0.20 Return (yrs)Cf 2 to 10 1 2. Calculate T c (Pre-Development)11 to 25 1.1 Tc Overland Flow 26 to 50 1.2 Tc = 1.87 (1.1-CCf)D1/2/S1/3 51 to 100 1.25 S = Slope of Basin (%)1.820 C = Rational Method Runoff Coefficient 0.2 Cf = Frequency Adjustment Factor 1 D = Length of Basin (ft)606 Tc (Pre-Development) (minutes)34 3. Calculate Rainfall Intensity (Duration = Pre-Development Tc) i = 0.64x-0.65 (10-yr Storm, Fig. I-3, COB Design Standards) x = storm duration (hrs)0.57 (Tc Pre-Development) i = rainfall intensity (in./hr.)0.93 4. Calculate Runoff Rate (Pre-Development) Q = CiA C = Rational Method Runoff Coefficient 0.2 (open land) i = rainfall intensity (in./hr.)0.93 (calculated above) A = Area (acres)5.48 (calculated above) Q = Runoff Rate (Pre-Development) (cfs)1.02 DA - EX 4 REQUIRED VOLUME 1. Calculate Area and Weighted C Factor (Post-Development) Contributing Area DA C Area (ft2 )C * Area Open Land EX 4 0.20 1709509 341902 Total 1709509 341902 A = Area (acres)39.24 Storm C = Weighted C Factor 0.20 Return (yrs)Cf 2 to 10 1 2. Calculate T c (Pre-Development)11 to 25 1.1 Tc Overland Flow 26 to 50 1.2 Tc = 1.87 (1.1-CCf)D1/2/S1/3 51 to 100 1.25 S = Slope of Basin (%)1.590 C = Rational Method Runoff Coefficient 0.2 Cf = Frequency Adjustment Factor 1 D = Length of Basin (ft)2345 Tc (Pre-Development) (minutes)70 3. Calculate Rainfall Intensity (Duration = Pre-Development Tc) i = 0.64x-0.65 (10-yr Storm, Fig. I-3, COB Design Standards) x = storm duration (hrs)1.16 (Tc Pre-Development) i = rainfall intensity (in./hr.)0.58 4. Calculate Runoff Rate (Pre-Development) Q = CiA C = Rational Method Runoff Coefficient 0.2 (open land) i = rainfall intensity (in./hr.)0.58 (calculated above) A = Area (acres)39.24 (calculated above) Q = Runoff Rate (Pre-Development) (cfs)4.55 APPENDIX C Post Development Drainage Area Calculations DRAINAGE AREA # 9A 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Local 0.76 14613 11106 Residential - Dense 0.75 88780 66585 Total 103393 77691 A = Area (acres)2.37 C = Weighted C Factor 0.75 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)1.00 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.75 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)380 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)10.02 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0144 L = length of gutter (ft)279 V = mean velocity (ft/s)3.60 Tc Gutter Flow (minutes) =1.29 Tc Total =11.32 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.75 (calculated above) I = 0.78 Tc-0.64 (in/hr)2.27 (25-yr storm) A = area (acres)2.37 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)4.05 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 0.15' Below Top of Curb Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0144 Q = PROVIDED GUTTER CAPACITY (cfs)4.46 REQ'D PIPE CAPACITY DA 9A 3.13 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:Pipe 9A Project:Blackwood Groves Phase 1 INPUT D= 12 inches d= 11.26 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.005 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 0.77 2.64 0.29 5.12 3.91 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 9B 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Local 0.76 31547 23976 Residential - Dense 0.60 114817 68890 Park 0.20 20901 4180 Total 167265 97046 A = Area (acres)3.84 C = Weighted C Factor 0.58 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)0.75 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.60 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)486 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)19.96 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0083 L = length of gutter (ft)245 V = mean velocity (ft/s)2.37 Tc Gutter Flow (minutes) =1.72 Tc Total =21.69 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.58 (calculated above) I = 0.78 Tc-0.64 (in/hr)1.50 (25-yr storm) A = area (acres)3.84 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)3.33 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 0.15' Below Top of Curb Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0083 Q = PROVIDED GUTTER CAPACITY (cfs)3.39 REQ'D PIPE CAPACITY DA 9B+Pipe 9C 7.69 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:Pipe 9B Project:Blackwood Groves Phase 1 INPUT D= 15 inches d= 14.07 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.0102 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 1.20 3.30 0.36 8.48 10.14 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 9B2 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Local 0.76 15281 11614 Residential - Dense 0.60 38754 23252 Total 54035 34866 A = Area (acres)1.24 C = Weighted C Factor 0.65 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)0.75 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.60 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)135 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)10.52 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0155 L = length of gutter (ft)370 V = mean velocity (ft/s)3.24 Tc Gutter Flow (minutes) =1.91 Tc Total =12.43 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.65 (calculated above) I = 0.78 Tc-0.64 (in/hr)2.14 (25-yr storm) A = area (acres)1.24 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)1.71 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 0.15' Below Top of Curb Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0083 Q = PROVIDED GUTTER CAPACITY (cfs)3.39 REQ'D PIPE CAPACITY DA 9B2 1.71 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:Pipe 9B2 Project:Blackwood Groves Phase 1 INPUT D= 15 inches d= 14.07 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.0265 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 1.20 3.30 0.36 13.67 16.34 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 9C 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Local 0.76 22307 16953 Commercial 0.95 26505 25180 Residential - Dense 0.75 45055 33791 Total 93867 75924 A = Area (acres)2.15 C = Weighted C Factor 0.81 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)1.00 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.75 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)304 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)8.97 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0144 L = length of gutter (ft)165 V = mean velocity (ft/s)2.92 Tc Gutter Flow (minutes) =0.94 Tc Total =9.91 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.81 (calculated above) I = 0.78 Tc-0.64 (in/hr)2.47 (25-yr storm) A = area (acres)2.15 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)4.31 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 0.15' Below Top of Curb Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0144 Q = PROVIDED GUTTER CAPACITY (cfs)5.80 REQ'D PIPE CAPACITY DA 9C 4.31 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:Pipe 9C Project:Blackwood Groves Subdivision Phase 1 INPUT D= 12 inches d= 11.26 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.006 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 0.77 2.64 0.29 5.67 4.34 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 9D 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area Residential - Dense 0.40 11619 4647 OS 0.20 3357 671 ROW - Local 0.76 12697 9649 Total 27672 14968 A = Area (acres)0.64 C = Weighted C Factor 0.54 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)1.50 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.40 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)108 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)11.20 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0075 L = length of gutter (ft)157 V = mean velocity (ft/s)2.60 Tc Gutter Flow (minutes) =1.01 Tc Total =12.21 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.54 (calculated above) I = 0.78 Tc-0.64 (in/hr)2.16 (25-yr storm) A = area (acres)0.64 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)0.74 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 0.15' Below Top of Curb Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0075 Q = PROVIDED GUTTER CAPACITY (cfs)3.22 REQ'D PIPE CAPACITY Pipe 9B + DA 9D 9.67 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:Pipe 9D Project:Blackwood Groves Phase 1 INPUT D= 18 inches d= 16.88 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.0081 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 1.72 3.96 0.44 8.53 14.69 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D REQ'D PIPE CAPACITY Pipe 9D + Pipe 9I + Pipe 9A 16.92 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe: Pipe 9D2 Project: Blackwood Groves Phase 1 INPUT D=21 inches d= 19.70 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.0055 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 2.34 4.62 0.51 7.79 18.26 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 9E 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Local 0.76 21527 16360 Residential - Dense 0.75 102610 76958 Total 124137 93318 A = Area (acres)2.85 C = Weighted C Factor 0.75 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)1.00 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.75 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)480 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)12.17 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0152 L = length of gutter (ft)70 V = mean velocity (ft/s)3.70 Tc Gutter Flow (minutes) =0.32 Tc Total =12.48 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.75 (calculated above) I = 0.78 Tc-0.64 (in/hr)2.13 (25-yr storm) A = area (acres)2.85 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)4.56 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 0.15' Below Top of Curb Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0152 Q = PROVIDED GUTTER CAPACITY (cfs)4.58 REQ'D PIPE CAPACITY Pipe 9D2 + Pipe 9G + DA 9E 25.61 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:Pipe 9E Project:Blackwood Groves Phase 1 INPUT D= 21 inches d= 19.70 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.0112 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 2.34 4.62 0.51 11.12 26.05 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 9F 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Local 0.76 7859 5973 Total 7859 5973 A = Area (acres)0.18 C = Weighted C Factor 0.76 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)2.00 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.50 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)15 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)3.16 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0126 L = length of gutter (ft)207 V = mean velocity (ft/s)3.37 Tc Gutter Flow (minutes) =1.03 Tc Total =4.19 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.76 (calculated above) I = 0.78 Tc-0.64 (in/hr)4.29 (25-yr storm) A = area (acres)0.18 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)0.59 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 0.15' Below Top of Curb Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0126 Q = PROVIDED GUTTER CAPACITY (cfs)4.17 REQ'D PIPE CAPACITY Pipe 9E + DA 9F 26.20 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:Pipe 9F Project:Blackwood Groves Phase 1 INPUT D= 24 inches d= 22.51 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.006 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 3.06 5.28 0.58 8.90 27.23 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 9G 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Local 0.76 9046 6875 Park 0.20 4251 850 OS 0.20 13120 2624 Residential - Dense 0.60 35478 21287 Total 61894 31636 A = Area (acres)1.42 C = Weighted C Factor 0.51 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)1.00 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.60 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)270 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)13.52 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0152 L = length of gutter (ft)176 V = mean velocity (ft/s)3.70 Tc Gutter Flow (minutes) =0.79 Tc Total =14.31 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.51 (calculated above) I = 0.78 Tc-0.64 (in/hr)1.95 (25-yr storm) A = area (acres)1.42 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)1.42 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 0.15' Below Top of Curb Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0152 Q = PROVIDED GUTTER CAPACITY (cfs)4.58 REQ'D PIPE CAPACITY DA 9G 6.25 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:Pipe 9G Project:Blackwood Groves Subdivision Phase 1 INPUT D= 12 inches d= 11.26 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.0183 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 0.77 2.64 0.29 9.79 7.49 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 9H 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Local 0.76 17977 13662 Residential - Low-Med 0.35 20009 7003 Total 37985 20665 A = Area (acres)0.87 C = Weighted C Factor 0.54 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)2.00 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.35 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)97 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)10.45 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0180 L = length of gutter (ft)272 V = mean velocity (ft/s)4.02 Tc Gutter Flow (minutes) =1.13 Tc Total =11.58 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.54 (calculated above) I = 0.78 Tc-0.64 (in/hr)2.24 (25-yr storm) A = area (acres)0.87 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)1.06 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 0.15' Below Top of Curb Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0180 Q = PROVIDED GUTTER CAPACITY (cfs)4.99 REQ'D PIPE CAPACITY DA 9H 1.06 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:Pipe 9H Project:Blackwood Groves Subdivision Phase 1 INPUT D= 12 inches d= 11.26 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.0038 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 0.77 2.64 0.29 4.46 3.41 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 9I 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Local 0.76 11917 9057 Residential - Dense 0.75 41833 31375 Total 53749 40431 A = Area (acres)1.23 C = Weighted C Factor 0.75 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)1.50 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.50 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)41 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)5.75 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0050 L = length of gutter (ft)963 V = mean velocity (ft/s)2.12 Tc Gutter Flow (minutes) =7.57 Tc Total =13.32 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.75 (calculated above) I = 0.78 Tc-0.64 (in/hr)2.04 (25-yr storm) A = area (acres)1.23 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)1.90 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 0.15' Below Top of Curb Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0050 Q = PROVIDED GUTTER CAPACITY (cfs)2.63 REQ'D PIPE CAPACITY DA 9I 1.90 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:Pipe 9I Project:Blackwood Groves Subdivision Phase 1 INPUT D= 12 inches d= 11.26 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.005 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 0.77 2.64 0.29 5.12 3.91 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 9J 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Collector 0.70 41138 28797 Total 41138 28797 A = Area (acres)0.94 C = Weighted C Factor 0.70 2. Assume min. Tc (will be designed in Phase 2) Tc Total =5.00 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.70 (calculated above) I = 0.78 Tc-0.64 (in/hr)3.83 (25-yr storm) A = area (acres)0.94 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)2.53 (assuming no carry flow) DRAINAGE AREA # 9K 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Local 0.76 5714 4343 Residential - Low-Med 0.35 12487 4370 Total 18201 8713 A = Area (acres)0.42 C = Weighted C Factor 0.48 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)1.50 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.35 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)125 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)13.06 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0060 L = length of gutter (ft)90 V = mean velocity (ft/s)2.32 Tc Gutter Flow (minutes) =0.65 Tc Total =13.70 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.48 (calculated above) I = 0.78 Tc-0.64 (in/hr)2.01 (25-yr storm) A = area (acres)0.42 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)0.40 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 0.15' Below Top of Curb Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0060 Q = PROVIDED GUTTER CAPACITY (cfs)2.88 REQ'D PIPE CAPACITY DA 9K + Pipe 9H 1.46 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:Pipe 9k Project:Blackwood Groves Subdivision Phase 1 INPUT D= 12 inches d= 11.26 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.005 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 0.77 2.64 0.29 5.12 3.91 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 9L 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area Residential - Dense 0.75 103406 77554 OS 0.20 50963 10193 Total 154369 87747 A = Area (acres)3.54 C = Weighted C Factor 0.57 2. Assume min. Tc (will be designed during site plan review) Tc Total =5.00 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.57 (calculated above) I = 0.78 Tc-0.64 (in/hr)3.83 (25-yr storm) A = area (acres)3.54 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)7.71 (assuming no carry flow) DRAINAGE AREA # 8A 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Local 0.76 36398 27663 ROW - Angled 0.93 20802 19346 Commercial 0.95 43975 41776 Park 0.20 12172 2434 OS 0.20 13111 2622 Residential - Dense 0.40 99407 39763 Total 225866 133604 A = Area (acres)5.19 C = Weighted C Factor 0.59 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)1.00 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.40 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)360 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)23.42 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0160 L = length of gutter (ft)535 V = mean velocity (ft/s)3.79 Tc Gutter Flow (minutes) =2.35 Tc Total =25.77 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.59 (calculated above) I = 0.78 Tc-0.64 (in/hr)1.34 (25-yr storm) A = area (acres)5.19 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)4.11 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 0.15' Below Top of Curb Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0160 Q = PROVIDED GUTTER CAPACITY (cfs)4.70 REQ'D PIPE CAPACITY DA 8A 4.11 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:Pipe 8A Project:Blackwood Groves Subdivision Phase 1 INPUT D= 12 inches d= 11.26 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.0096 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 0.77 2.64 0.29 7.09 5.42 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 8B 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Local 0.76 8489 6452 ROW - Angled 0.93 31758 29535 Total 40247 35987 A = Area (acres)0.92 C = Weighted C Factor 0.89 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)1.50 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.50 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)23 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)4.31 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0165 L = length of gutter (ft)985 V = mean velocity (ft/s)3.85 Tc Gutter Flow (minutes) =4.26 Tc Total =8.57 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.89 (calculated above) I = 0.78 Tc-0.64 (in/hr)2.71 (25-yr storm) A = area (acres)0.92 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)2.24 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 0.15' Below Top of Curb Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0165 Q = PROVIDED GUTTER CAPACITY (cfs)4.78 REQ'D PIPE CAPACITY DA 8B + Pipe 8B3 + 8B2 9.24 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:Pipe 8B Project:Blackwood Groves Subdivision Phase 1 INPUT D= 15 inches d= 14.07 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.0085 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 1.20 3.30 0.36 7.74 9.25 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 8B2 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area Commercial 0.95 81017 76966 Total 81017 76966 A = Area (acres)1.86 C = Weighted C Factor 0.95 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)0.50 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.95 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)595 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)5.75 Tc Total = (5 min Minimum )5.75 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.95 (calculated above) I = 0.78 Tc-0.64 (in/hr)3.50 (25-yr storm) A = area (acres)1.86 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)6.18 (assuming no carry flow) REQ'D PIPE CAPACITY DA 8B2 6.18 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:Pipe 8B2 Project:Blackwood Groves Subdivision Phase 1 INPUT D= 15 inches d= 14.07 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.0055 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 1.20 3.30 0.36 6.23 7.44 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 8B3 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area Residential - Dense 0.40 59972 23989 Total 59972 23989 A = Area (acres)1.38 C = Weighted C Factor 0.40 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)1.00 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.40 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)313 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)21.84 Tc Total =21.84 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.40 (calculated above) I = 0.78 Tc-0.64 (in/hr)1.49 (25-yr storm) A = area (acres)1.38 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)0.82 (assuming no carry flow) REQ'D PIPE CAPACITY DA 8B3 0.82 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:Pipe 8B3 Project:Blackwood Groves Subdivision Phase 1 INPUT D= 15 inches d= 14.07 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.0055 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 1.20 3.30 0.36 6.23 7.44 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 8C 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Local 0.76 11853 9008 Residential - Low-Med 0.35 25880 9058 Total 37733 18066 A = Area (acres)0.87 C = Weighted C Factor 0.48 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)1.50 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.35 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)114 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)12.47 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0053 L = length of gutter (ft)310 V = mean velocity (ft/s)2.18 Tc Gutter Flow (minutes) =2.37 Tc Total =14.84 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.48 (calculated above) I = 0.78 Tc-0.64 (in/hr)1.91 (25-yr storm) A = area (acres)0.87 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)0.79 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 0.15' Below Top of Curb Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0053 Q = PROVIDED GUTTER CAPACITY (cfs)2.71 REQ'D PIPE CAPACITY PIPE 8A + DA 8C 4.90 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:Pipe 8C Project:Blackwood Groves Subdivision Phase 1 INPUT D= 15 inches d= 14.07 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.005 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 1.20 3.30 0.36 5.94 7.10 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 8D 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Local 0.76 28957 22007 ROW - Alley 0.80 10487 8390 Park 0.20 19843 3969 Residential - Low-Med 0.35 104870 36704 Total 164156 71070 A = Area (acres)3.77 C = Weighted C Factor 0.43 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)1.00 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.35 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)118 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)14.52 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0050 L = length of gutter (ft)615 V = mean velocity (ft/s)2.12 Tc Gutter Flow (minutes) =4.83 Tc Total =19.36 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.43 (calculated above) I = 0.78 Tc-0.64 (in/hr)1.61 (25-yr storm) A = area (acres)3.77 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)2.62 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 0.15' Below Top of Curb Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0050 Q = PROVIDED GUTTER CAPACITY (cfs)2.63 REQ'D PIPE CAPACITY DA 8D 2.62 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:Pipe 8D Project:Blackwood Groves Subdivision Phase 1 INPUT D= 12 inches d= 11.26 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.005 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Manning's n-values Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 0.77 2.64 0.29 5.12 3.91 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 d q D REQ'D PIPE CAPACITY PIPE 8B + Pipe 8D 11.87 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:Pipe 8D2 Project:Blackwood Groves Subdivision Phase 1 INPUT D= 18 inches d= 16.88 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.006 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Manning's n-values Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 1.72 3.96 0.44 7.34 12.64 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 d q D DRAINAGE AREA # 8E 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Local 0.76 12430 9447 Residential - Low-Med 0.35 22158 7755 Total 34588 17202 A = Area (acres)0.79 C = Weighted C Factor 0.50 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)1.50 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.35 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)116 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)12.58 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0087 L = length of gutter (ft)141 V = mean velocity (ft/s)2.80 Tc Gutter Flow (minutes) =0.84 Tc Total =13.42 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.50 (calculated above) I = 0.78 Tc-0.64 (in/hr)2.03 (25-yr storm) A = area (acres)0.79 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)0.80 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 0.15' Below Top of Curb Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0087 Q = PROVIDED GUTTER CAPACITY (cfs)3.47 REQ'D PIPE CAPACITY PIPE 8C + DA 8E 5.70 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:Pipe 8E Project:Blackwood Groves Subdivision Phase 1 INPUT D= 15 inches d= 14.07 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.005 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 1.20 3.30 0.36 5.94 7.10 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 8F 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Local 0.76 6521 4956 Residential - Low-Med 0.35 19747 6911 Total 26268 11867 A = Area (acres)0.60 C = Weighted C Factor 0.45 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)1.50 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.35 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)131 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)13.37 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0094 L = length of gutter (ft)154 V = mean velocity (ft/s)2.91 Tc Gutter Flow (minutes) =0.88 Tc Total =14.25 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.45 (calculated above) I = 0.78 Tc-0.64 (in/hr)1.96 (25-yr storm) A = area (acres)0.60 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)0.53 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 0.15' Below Top of Curb Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0094 Q = PROVIDED GUTTER CAPACITY (cfs)3.60 REQ'D PIPE CAPACITY PIPE 8E + DA 8F 6.24 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:Pipe 8F Project:Blackwood Groves Subdivision Phase 1 INPUT D= 15 inches d= 14.07 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.005 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 1.20 3.30 0.36 5.94 7.10 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 8G 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Local 0.76 16169 12288 Residential - Low-Med 0.35 48000 16800 Total 64169 29088 A = Area (acres)1.47 C = Weighted C Factor 0.45 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)1.00 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.35 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)133 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)15.42 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0050 L = length of gutter (ft)422 V = mean velocity (ft/s)2.12 Tc Gutter Flow (minutes) =3.32 Tc Total =18.74 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.45 (calculated above) I = 0.78 Tc-0.64 (in/hr)1.64 (25-yr storm) A = area (acres)1.47 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)1.10 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 0.15' Below Top of Curb Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0050 Q = PROVIDED GUTTER CAPACITY (cfs)2.63 REQ'D PIPE CAPACITY PIPE 8D + DA 8G 12.97 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:Pipe 8G Project:Blackwood Groves Subdivision Phase 1 INPUT D= 18 inches d= 16.88 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.007 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 1.72 3.96 0.44 7.93 13.66 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 8H 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Local 0.76 2300 1748 OS 0.20 4500 900 Total 6800 1748 A = Area (acres)0.16 C = Weighted C Factor 0.26 Tc Total =5.00 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.26 (calculated above) I = 0.78 Tc-0.64 (in/hr)3.83 (25-yr storm) A = area (acres)0.16 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)0.15 (assuming no carry flow) DRAINAGE AREA # 8I 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Local 0.76 2548 1937 OS 0.20 4435 887 Total 6983 2824 A = Area (acres)0.16 C = Weighted C Factor 0.40 Tc Total =5.00 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.40 (calculated above) I = 0.78 Tc-0.64 (in/hr)3.83 (25-yr storm) A = area (acres)0.16 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)0.25 (assuming no carry flow) DRAINAGE AREA # 8J 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Local 0.76 16953 12885 Park 0.20 16304 3261 Residential - Dense 0.40 23902 9561 Total 57159 25706 A = Area (acres)1.31 C = Weighted C Factor 0.45 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)1.00 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.40 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)206 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)17.71 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0165 L = length of gutter (ft)206 V = mean velocity (ft/s)3.85 Tc Gutter Flow (minutes) =0.89 Tc Total =18.61 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.45 (calculated above) I = 0.78 Tc-0.64 (in/hr)1.65 (25-yr storm) A = area (acres)1.31 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)0.97 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 0.15' Below Top of Curb Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0165 Q = PROVIDED GUTTER CAPACITY (cfs)4.78 REQ'D PIPE CAPACITY DA 8J 0.97 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:Pipe 8J Project:Blackwood Groves Subdivision Phase 1 INPUT D= 12 inches d= 11.26 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.005 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 0.77 2.64 0.29 5.12 3.91 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 8K 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Local 0.76 8897 6762 Residential - Low-Med 0.35 15988 5596 Total 24885 12358 A = Area (acres)0.57 C = Weighted C Factor 0.50 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)1.00 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.35 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)105 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)13.70 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0100 L = length of gutter (ft)204 V = mean velocity (ft/s)3.00 Tc Gutter Flow (minutes) =1.13 Tc Total =14.83 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.50 (calculated above) I = 0.78 Tc-0.64 (in/hr)1.91 (25-yr storm) A = area (acres)0.57 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)0.54 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 0.15' Below Top of Curb Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0100 Q = PROVIDED GUTTER CAPACITY (cfs)3.72 REQ'D PIPE CAPACITY Pipe 8J + DA 8K 1.52 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:Pipe 8K Project:Blackwood Groves Subdivision Phase 1 INPUT D= 15 inches d= 14.07 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.004 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 1.20 3.30 0.36 5.31 6.35 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 8L 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Local 0.76 34076 25898 Park 0.20 4800 960 Residential - Dense 0.40 35468 14187 OS 0.20 3410 682 Total 77755 41727 A = Area (acres)1.79 C = Weighted C Factor 0.54 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)1.00 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.40 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)174 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)16.28 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0130 L = length of gutter (ft)519 V = mean velocity (ft/s)3.42 Tc Gutter Flow (minutes) =2.53 Tc Total =18.81 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.54 (calculated above) I = 0.78 Tc-0.64 (in/hr)1.64 (25-yr storm) A = area (acres)1.79 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)1.57 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 0.15' Below Top of Curb Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0130 Q = PROVIDED GUTTER CAPACITY (cfs)4.24 REQ'D PIPE CAPACITY DA 8L 1.57 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:Pipe 8L Project:Blackwood Groves Subdivision Phase 1 INPUT D= 15 inches d= 14.07 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.005 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 1.20 3.30 0.36 5.94 7.10 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D REQ'D PIPE CAPACITY Pipe 8L + Pipe 8K + Pipe 8N 3.36 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:Pipe 8L2 Project:Blackwood Groves Subdivision Phase 1 INPUT D= 15 inches d= 14.07 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.004 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 1.20 3.30 0.36 5.31 6.35 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 8M 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Local 0.76 13224 10051 Residential - Low-Med 0.35 38062 13322 Total 51286 23372 A = Area (acres)1.18 C = Weighted C Factor 0.46 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)1.00 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.35 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)124 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)14.89 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0050 L = length of gutter (ft)222 V = mean velocity (ft/s)2.12 Tc Gutter Flow (minutes) =1.75 Tc Total =16.63 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.46 (calculated above) I = 0.78 Tc-0.64 (in/hr)1.77 (25-yr storm) A = area (acres)1.18 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)0.95 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 0.15' Below Top of Curb Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0050 Q = PROVIDED GUTTER CAPACITY (cfs)2.63 REQ'D PIPE CAPACITY Pipe 8L2 + DA 8M 4.31 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:Pipe 8M Project:Blackwood Groves Subdivision Phase 1 INPUT D= 15 inches d= 14.07 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.005 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 1.20 3.30 0.36 5.94 7.10 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 8N 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Local 0.76 3580 2721 Residential - Low-Med 0.35 9242 3235 Total 12822 5955 A = Area (acres)0.29 C = Weighted C Factor 0.46 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)1.00 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.35 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)101 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)13.44 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0050 L = length of gutter (ft)45 V = mean velocity (ft/s)2.12 Tc Gutter Flow (minutes) =0.35 Tc Total =13.79 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.46 (calculated above) I = 0.78 Tc-0.64 (in/hr)2.00 (25-yr storm) A = area (acres)0.29 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)0.27 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 0.15' Below Top of Curb Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0050 Q = PROVIDED GUTTER CAPACITY (cfs)2.63 REQ'D PIPE CAPACITY DA 8N 0.27 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:Pipe 8N Project:Blackwood Groves Subdivision Phase 1 INPUT D= 12 inches d= 11.26 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.005 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 0.77 2.64 0.29 5.12 3.91 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 6A 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Alley 0.80 17950 14360 OS 0.20 2253 451 Residential - Dense 0.75 96773 72580 Total 116975 87390 A = Area (acres)2.69 C = Weighted C Factor 0.75 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)2.00 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.75 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)144 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)4.90 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0175 L = length of gutter (ft)478 V = mean velocity (ft/s)3.97 Tc Gutter Flow (minutes) =2.01 Tc Total =6.91 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.75 (calculated above) I = 0.78 Tc-0.64 (in/hr)3.11 (25-yr storm) A = area (acres)2.69 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)6.24 (assuming no carry flow) DRAINAGE AREA # 6B 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Collector 0.70 28881 20216 ROW - Angled 0.93 6517 6061 Total 35398 26277 A = Area (acres)0.81 C = Weighted C Factor 0.74 2. Calculate Tc (Time to Concentration) Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0134 L = length of gutter (ft)828 V = mean velocity (ft/s)3.47 Tc Gutter Flow (minutes) =3.98 Tc Total =3.98 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.74 (calculated above) I = 0.78 Tc-0.64 (in/hr)4.43 (25-yr storm) A = area (acres)0.81 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)2.67 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 9 feet into Drive Aisle Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0134 Q = PROVIDED GUTTER CAPACITY (cfs)4.30 REQ'D PIPE CAPACITY DA 6B 2.67 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:PIPE 6B Project:Blackwood Groves Subdivision Phase 1 INPUT D= 12 inches d= 11.26 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.006 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 0.77 2.64 0.29 5.60 4.29 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 6C 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area OS 0.20 8017 1603 Total 8017 1603 A = Area (acres)0.18 C = Weighted C Factor 0.20 2. Calculate Tc (Time to Concentration) Tc Total =5.00 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.20 (calculated above) I = 0.78 Tc-0.64 (in/hr)3.83 (25-yr storm) A = area (acres)0.18 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)0.14 (assuming no carry flow) DRAINAGE AREA # 7A 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Collector 0.70 49013 34309 ROW - Angled 0.93 6218 5783 Commercial 0.95 131497 124922 Total 186728 165014 A = Area (acres)4.29 C = Weighted C Factor 0.88 2. Assume min. Tc (will be designed in Phase 3) Tc Total =5.00 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.88 (calculated above) I = 0.78 Tc-0.64 (in/hr)3.83 (25-yr storm) A = area (acres)4.29 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)14.49 (assuming no carry flow) DRAINAGE AREA # 7B 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Collector 0.70 3550 2485 ROW - Local 0.76 16101 12237 Residential - Dense 0.75 37248 28048 Total 56899 42769 A = Area (acres)1.31 C = Weighted C Factor 0.75 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)1.50 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.75 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)125 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)5.02 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0074 L = length of gutter (ft)379 V = mean velocity (ft/s)2.58 Tc Gutter Flow (minutes) =2.45 Tc Total =7.47 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.75 (calculated above) I = 0.78 Tc-0.64 (in/hr)2.96 (25-yr storm) A = area (acres)1.31 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)2.91 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 9 feet into Drive Aisle Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0074 Q = PROVIDED GUTTER CAPACITY (cfs)3.20 REQ'D PIPE CAPACITY DA 7B 2.91 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:PIPE 7B Project:Blackwood Groves Subdivision Phase 1 INPUT D= 12 inches d= 11.26 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.02 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 0.77 2.64 0.29 10.23 7.83 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 7C 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Collector 0.70 16245 11372 ROW - Local 0.76 13401 10185 Residential - Low-Med 0.35 62558 21895 Total 92204 21556 A = Area (acres)2.12 C = Weighted C Factor 0.23 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)2.00 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.35 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)123 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)11.77 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0120 L = length of gutter (ft)499 V = mean velocity (ft/s)3.28 Tc Gutter Flow (minutes) =2.53 Tc Total =14.30 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.23 (calculated above) I = 0.78 Tc-0.64 (in/hr)1.95 (25-yr storm) A = area (acres)2.12 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)0.97 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 9 feet into Drive Aisle Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0120 Q = PROVIDED GUTTER CAPACITY (cfs)4.07 REQ'D PIPE CAPACITY DA 7C 0.97 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:PIPE 7C Project:Blackwood Groves Subdivision Phase 1 INPUT D= 12 inches d= 11.26 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.003 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 0.77 2.64 0.29 3.96 3.03 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 7D 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Collector 0.70 84687 59281 Total 84687 59281 A = Area (acres)1.94 C = Weighted C Factor 0.70 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)2.00 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.50 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)37 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)4.97 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0150 L = length of gutter (ft)597 V = mean velocity (ft/s)3.67 Tc Gutter Flow (minutes) =2.71 Tc Total =7.67 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.70 (calculated above) I = 0.78 Tc-0.64 (in/hr)2.91 (25-yr storm) A = area (acres)1.94 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)3.96 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 9 feet into Drive Aisle Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0150 Q = PROVIDED GUTTER CAPACITY (cfs)4.55 REQ'D PIPE CAPACITY DA 7D + DA 7A 18.45 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:PIPE 7D Project:Blackwood Groves Subdivision Phase 1 INPUT D= 21 inches d= 19.70 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.006 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 2.34 4.62 0.51 8.14 19.07 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 7E 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Collector 0.70 6785 4750 ROW - Local 0.76 4125 3135 Total 10911 7885 A = Area (acres)0.25 C = Weighted C Factor 0.72 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)2.00 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.50 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)48 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)5.66 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0170 L = length of gutter (ft)182 V = mean velocity (ft/s)3.91 Tc Gutter Flow (minutes) =0.78 Tc Total =6.43 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.72 (calculated above) I = 0.78 Tc-0.64 (in/hr)3.26 (25-yr storm) A = area (acres)0.25 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)0.59 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 9 feet into Drive Aisle Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0170 Q = PROVIDED GUTTER CAPACITY (cfs)4.85 REQ'D PIPE CAPACITY DA 7E 0.59 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:PIPE 7E Project:Blackwood Groves Subdivision Phase 1 INPUT D= 12 inches d= 11.26 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.005 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 0.77 2.64 0.29 5.12 3.91 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 7F 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Collector 0.70 1075 753 ROW - Local 0.76 3465 2634 Total 4541 3386 A = Area (acres)0.10 C = Weighted C Factor 0.75 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)2.00 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.50 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)20 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)3.65 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0040 L = length of gutter (ft)53 V = mean velocity (ft/s)1.90 Tc Gutter Flow (minutes) =0.47 Tc Total =4.12 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.75 (calculated above) I = 0.78 Tc-0.64 (in/hr)4.33 (25-yr storm) A = area (acres)0.10 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)0.34 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 9 feet into Drive Aisle Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0040 Q = PROVIDED GUTTER CAPACITY (cfs)2.35 REQ'D PIPE CAPACITY PIPE 7E + DA 7F 0.93 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:PIPE 7F Project:Blackwood Groves Subdivision Phase 1 INPUT D= 12 inches d= 11.26 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.005 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 0.77 2.64 0.29 5.12 3.91 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D REQ'D PIPE CAPACITY PIPE 7B + PIPE 7F + PIPE 7D 22.28 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:PIPE 7F2 Project:Blackwood Groves Subdivision Phase 1 INPUT D= 21 inches d= 19.70 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.0086 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 2.34 4.62 0.51 9.74 22.83 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 7G 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Collector 0.70 14593 10215 Total 14593 10215 A = Area (acres)0.34 C = Weighted C Factor 0.70 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)2.00 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.50 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)22 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)3.83 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0135 L = length of gutter (ft)182 V = mean velocity (ft/s)3.48 Tc Gutter Flow (minutes) =0.87 Tc Total =4.70 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.70 (calculated above) I = 0.78 Tc-0.64 (in/hr)3.98 (25-yr storm) A = area (acres)0.34 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)0.93 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 9 feet into Drive Aisle Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0135 Q = PROVIDED GUTTER CAPACITY (cfs)4.32 REQ'D PIPE CAPACITY DA 7G 0.93 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:PIPE 7G Project:Blackwood Groves Subdivision Phase 1 INPUT D= 12 inches d= 11.26 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.0032 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 0.77 2.64 0.29 4.09 3.13 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D REQ'D PIPE CAPACITY PIPE 7F2 + PIPE 7G + PIPE 7C 24.18 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe: PIPE 7G2 Project: Blackwood Groves Subdivision Phase 1 INPUT D=21 inches d= 19.70 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.01 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 2.34 4.62 0.51 10.51 24.62 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 7H 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area PARK 0.20 21814 4363 ROW - Collector 0.70 5189 3633 Total 27003 7995 A = Area (acres)0.62 C = Weighted C Factor 0.30 2. Calculate Tc (Time to Concentration) Tc Total =5.00 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.30 (calculated above) I = 0.78 Tc-0.64 (in/hr)3.83 (25-yr storm) A = area (acres)0.62 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)0.70 (assuming no carry flow) DRAINAGE AREA # 5A 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Local 0.76 31128 23657 ROW - Angled 0.93 16099 14972 Commercial 0.95 95851 91058 Total 143078 129688 A = Area (acres)3.28 C = Weighted C Factor 0.91 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)1.00 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.95 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)650 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)4.77 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0152 L = length of gutter (ft)361 V = mean velocity (ft/s)3.70 Tc Gutter Flow (minutes) =1.63 Tc Total =6.40 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.91 (calculated above) I = 0.78 Tc-0.64 (in/hr)3.27 (25-yr storm) A = area (acres)3.28 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)9.73 (assuming no carry flow) REQ'D PIPE CAPACITY DA 5A 9.73 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:PIPE 5A Project:Blackwood Groves Subdivision Phase 1 INPUT D= 18 inches d= 16.88 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.005 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 1.72 3.96 0.44 6.70 11.54 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 5B 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Angled 0.93 12707 11818 ROW - Local 0.76 13202 10033 Park 0.20 15270 3054 Residential - Dense 0.75 44174 33131 Total 85354 58036 A = Area (acres)1.96 C = Weighted C Factor 0.68 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)1.00 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.75 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)217 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)7.58 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0080 L = length of gutter (ft)350 V = mean velocity (ft/s)2.68 Tc Gutter Flow (minutes) =2.18 Tc Total =9.75 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.68 (calculated above) I = 0.78 Tc-0.64 (in/hr)2.50 (25-yr storm) A = area (acres)1.96 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)3.32 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 9 feet into Drive Aisle Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0080 Q = PROVIDED GUTTER CAPACITY (cfs)3.33 REQ'D PIPE CAPACITY DA 5B 3.33 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:PIPE 5B Project:Blackwood Groves Subdivision Phase 1 INPUT D= 15 inches d= 14.07 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.005 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 1.20 3.30 0.36 5.94 7.10 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # 5C 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Angled 0.93 8517 7921 ROW - Local 0.76 13607 10341 Park 0.20 24597 4919 Total 46720 23181 A = Area (acres)1.07 C = Weighted C Factor 0.50 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)1.00 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.75 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)216 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)7.56 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0077 L = length of gutter (ft)350 V = mean velocity (ft/s)2.63 Tc Gutter Flow (minutes) =2.22 Tc Total =9.77 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.50 (calculated above) I = 0.78 Tc-0.64 (in/hr)2.49 (25-yr storm) A = area (acres)1.07 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)1.33 (assuming no carry flow) PROVIDED GUTTER CAPACITY 1. Calculate Gutter Capacity @ 9 feet into Drive Aisle Q = (1.486/n)AR2/3 S1/2 n = Mannings Coefficient 0.013 A = Area (ft2)1.24 (0.15' below top of curb) P = Wetted perimeter (ft)9.23 (0.15' below top of curb) R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0077 Q = PROVIDED GUTTER CAPACITY (cfs)3.26 REQ'D PIPE CAPACITY PIPE 5B + PIPE 5A + DA 5C 14.38 cfs MANNING'S EQUATION FOR PIPE FLOW Pipe:PIPE 5C Project:Blackwood Groves Subdivision Phase 1 INPUT D= 21 inches d= 19.70 inches Mannings Formula n= 0.009 mannings q=57.7 degrees Q=(1.486/n)ARh2/3S1/2 S= 0.004 slope in/in R=A/P A=cross sectional area P=wetted perimeter S=slope of channel V=(1.49/n)Rh2/3S1/2 n=Manning's roughness coefficient Q=V x A Solution to Mannings Equation Area,ft2 Wetted Perimeter, ft Hydraulic Radius, ft velocity ft/s flow, cfs PVC 0.013 2.34 4.62 0.51 6.64 15.57 PE (<9"dia) 0.015 PE (>12"dia) 0.02 PE(9-12"dia) 0.017 CMP 0.025 ADS N12 0.012 HCMP 0.023 Conc 0.013 Manning's n-values d q D DRAINAGE AREA # ALDER CREEK SPRING RIDGE AND S. 15TH 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 ) C * Area ROW - Local 0.76 12000 9120 Total 12000 9120 A = Area (acres)0.28 C = Weighted C Factor 0.76 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)1.00 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.50 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)380 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)20.05 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0144 L = length of gutter (ft)279 V = mean velocity (ft/s)3.60 Tc Gutter Flow (minutes) =1.29 Tc Total =21.34 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.76 (calculated above) I = 0.78 Tc-0.64 (in/hr)1.51 (25-yr storm) A = area (acres)0.28 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)0.32 (assuming no carry flow) 4. Calculate Additional Runoff Volume Q = CIA V=7200Q C = Weighted C Factor 0.76 I = intensity (in/hr) 0.41 (10 yr, 2hr storm) A = Area (acres)0.28 Q = runoff (cfs)0.09 V = REQUIRED VOL (ft3)618 DRAINAGE AREA # ALDER CREEK S. 11TH 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 ) C * Area ROW - Collector 0.70 5386 3770 Total 5386 3770 A = Area (acres)0.12 C = Weighted C Factor 0.70 2. Calculate Tc (Time to Concentration) Tc Overland Flow Tc = 1.87 (1.1-CCf)D1/2/S1/3 Storm S = Slope of Basin (%)1.00 Return (yrs)Cf C = Rational Method Runoff Coefficient 0.50 2 to 10 1 Cf = Frequency Adjustment Factor 1.1 11 to 25 1.1 D = Length of Basin (ft)380 26 to 50 1.2 51 to 100 1.25 Tc Overland Flow (minutes)20.05 Tc Gutter Flow Tc = L/V/60 V = (1.486/n)R2/3 S1/2 n = Mannings Coefficient 0.013 R = Hydraulic Radius A/P (ft)0.13 (0.15' below top of curb) S = slope (ft/ft)0.0144 L = length of gutter (ft)279 V = mean velocity (ft/s)3.60 Tc Gutter Flow (minutes) =1.29 Tc Total =21.34 3. Calculate Flow (Rational Formula) Q = CIA C = Weighted C Factor 0.70 (calculated above) I = 0.78 Tc-0.64 (in/hr)1.51 (25-yr storm) A = area (acres)0.12 (calculated above) Q = REQUIRED GUTTER CAPACITY (cfs)0.13 (assuming no carry flow) 4. Calculate Additional Runoff Volume Q = CIA V=7200Q C = Weighted C Factor 0.70 I = intensity (in/hr) 0.41 (10 yr, 2hr storm) A = Area (acres)0.12 Q = runoff (cfs)0.04 V = REQUIRED VOL (ft3)255 APPENDIX D Pond Sizing Calculations POND 5 - Temporary Retention REQUIRED VOLUME 1. Calculate Area and Weighted C Factor (Post-Development) Contributing Area DA C Area (ft2 )C * Area ROW - Local 5 0.76 26808 20441 Total 26808 20441 A = Area (acres)0.62 C = Weighted C Factor 0.76 2. Calculate Required Volume Q = CIA V=7200Q C = Weighted C Factor 0.62 I = intensity (in/hr) 0.41 (10 yr, 2hr storm) A = Area (acres)0.62 Q = runoff (cfs)0.16 V = REQUIRED VOL (ft3)1118 Check the half inch requirement (per DSSP II.A.4) 1. Determine Area of Hardscape within Drainage Area #2 Contributing Area Area (ft2 ) Hardscape 20,106 2. Calculate 1/2" runoff volume over hardscape (aka Runoff Reduction Volume [RRV] as calculated in Montana Post- Construction Storwater BMP Manual - Equation 3-1) RRV = [P*Rv*A]/12 P = Water quality rainfall depth 0.50 inches Rv = Dimensionless runoff coefficient 0.73 0.05 + 0.9*I I = Percent impervious cover (decimal)0.75 decimal A = Entire drainage area 0.62 acres RRV = Runoff Reduction Volume 0.019 acre-ft RRV = Runoff Reduction Volume 810 cubic feet Because the runoff volume from the 10-yr, 2-hr storm (for flood control) is greater than the runoff volume produced by the half inch rainfall (for water quality) the temporary retention facility is sized to handle the larger volume (1,118 cf). Temporary Retention Pond A NORTH 100 FT OF AVENUE A 1. Calculate Area and Weighted C Factor Contributing Area C Area (ft 2 )C * Area ROW - Local 0.76 6816 5180 Total 6816 5180 A = Area (acres)0.16 C = Weighted C Factor 0.76 2. Calculate Required Volume Q = CIA V=7200Q C = Weighted C Factor 0.76 I = intensity (in/hr) 0.41 (10 yr, 2hr storm) A = Area (acres)0.16 Q = runoff (cfs)0.05 V = REQUIRED VOL (ft3)351 POND 6 - DETENTION REQUIRED VOLUME 1. Calculate Area and Weighted C Factor (Post-Development) Contributing Area DA C Area (ft 2)C * Area ROW - Collector 6B 0.70 28881 20216 ROW - Angled 6B 0.93 6517 6061 ROW - Alley 6A 0.80 17950 14360 OS 6C 0.20 8017 1603 OS 6A 0.20 2253 451 Residential - Dense 6A 0.75 96773 72580 Total 160390 115271 A = Area (acres)3.68 C = Weighted C Factor 0.72 2. Pre-Development Conditions Pre-Development Drainage Area Name = EX 4 Pre-Development Drainage Area Size = 39.24 (acres) Pre Development Tc =70 (minutes) Pre-Development Runoff Rate (Total) =4.55 (cfs) Pre-Development Runoff Rate (Pond 6) =1.00 (cfs) Pre-Development Runoff Rate (Pond 7) =1.90 (cfs) Pre-Development Runoff Rate (Total) =2.90 (cfs) 5. Calculate Required Pond Volume Total Area (acres) =3.68 acres Weighted C =0.72 Discharge Rate (cfs) =1.00 cfs (Equal to Pre-Development Runoff Rate) Duration(min)Duration(hrs)Intensity (in/hr)Qin (cfs)Runoff Volume Release Volume Required Storage (ft3) 24 0.40 1.16 3.07 4424 0 4424.20 25 0.42 1.13 2.99 4488 0 4487.86 26 0.43 1.10 2.92 4550 0 4549.89 27 0.45 1.08 2.85 4610 0 4610.39 28 0.47 1.05 2.78 4669 0 4669.45 29 0.48 1.03 2.72 4727 60 4667.15 30 0.50 1.00 2.66 4784 120 4663.58 31 0.52 0.98 2.60 4839 180 4658.79 32 0.53 0.96 2.55 4893 240 4652.86 33 0.55 0.94 2.50 4946 300 4645.84 PROVIDED VOLUME (ft3)4,777 OUTLET STRUCTURE SLOT Q=CLH3/2 Q = Discharge (cfs)1.00 C = Weir Coefficient 3.33 (per COB Design Standards) H = Head (ft)1.5 L = Horizontal Length (ft)0.16 L = Slot Width (inches)2.0 Check the half inch requirement (per DSSP II.A.4) 1. Determine Area of Hardscape within Drainage Basin Contributing Area Area (ft 2 ) Hardscape 110,924 2. Calculate 1/2" runoff volume over hardscape (aka Runoff Reduction Volume [RRV] as calculated in Montana Post- Construction Storwater BMP Manual - Equation 3-1) RRV = [P*Rv*A]/12 P = Water quality rainfall depth 0.50 inches Rv = Dimensionless runoff coefficient 0.67 0.05 + 0.9*I I = Percent impervious cover (decimal)0.69 decimal A = Entire drainage area 3.68 acres RRV = Runoff Reduction Volume 0.103 acre-ft RRV = Runoff Reduction Volume 4494 cubic feet POND 7 - DETENTION REQUIRED VOLUME 1. Calculate Area and Weighted C Factor (Post-Development) Contributing Area DA C Area (ft 2 )C * Area ROW - Collector 7A 0.70 49013 34309 ROW - Collector 7B 0.70 3550 2485 ROW - Collector 7C 0.70 16245 11372 ROW - Collector 7D 0.70 28687 20081 ROW - Collector 7E 0.70 6785 4750 ROW - Collector 7F 0.70 1075 753 ROW - Collector 7G 0.70 14593 10215 ROW - Collector 7H 0.70 5189 3633 ROW - Local 7B 0.76 16101 12237 ROW - Local 7C 0.76 13401 10218 ROW - Local 7E 0.76 4125 3135 ROW - Local 7F 0.76 3465 2634 ROW - Angled 7A 0.93 6218 5783 Park 7H 0.20 21814 4363 Commercial 7A 0.95 131497 124922 Residential - Dense 7B 0.75 37248 27936 Residential - Low-Med 7C 0.35 62558 21895 Total 421566 300720 A = Area (acres)9.68 C = Weighted C Factor 0.71 2. Pre-Development Conditions Pre-Development Drainage Area Name = EX 4 Pre-Development Drainage Area Size = 39.24 (acres) Pre Development Tc =70 (minutes) Pre-Development Runoff Rate (Total) =4.55 (cfs) Pre-Development Runoff Rate (Pond 6) =1.00 (cfs) Pre-Development Runoff Rate (Pond 7) =1.90 (cfs) Pre-Development Runoff Rate (Total) =2.90 (cfs) 5. Calculate Required Pond Volume Total Area (acres) =9.68 acres Weighted C =0.71 Discharge Rate (cfs) =1.90 cfs (Equal to Pre-Development Runoff Rate) Duration(min)Duration(hrs)Intensity (in/hr)Qin (cfs)Runoff Volume Release Volume Required Storage (ft3) 40 0.67 0.83 5.75 13,801 1,596 12,205 41 0.68 0.82 5.66 13,921 1,710 12,211 42 0.70 0.81 5.57 14,039 1,824 12,215 43 0.72 0.79 5.49 14,155 1,938 12,217 44 0.73 0.78 5.41 14,270 2,052 12,218 45 0.75 0.77 5.33 14,382 2,166 12,216 46 0.77 0.76 5.25 14,493 2,280 12,213 47 0.78 0.75 5.18 14,603 2,394 12,209 48 0.80 0.74 5.11 14,711 2,508 12,203 49 0.82 0.73 5.04 14,817 2,622 12,195 PROVIDED VOLUME (ft3)12,484 OUTLET STRUCTURE SLOT Q=CLH3/2 Q = Discharge (cfs)1.90 C = Weir Coefficient 3.33 (per COB Design Standards) H = Head (ft)1.5 L = Horizontal Length (ft)0.31 L = Slot Width (inches)3.7 Check the half inch requirement (per DSSP II.A.4) 1. Determine Area of Hardscape within Drainage Basin Contributing Area Area (ft 2 ) Hardscape 288,542 2. Calculate 1/2" runoff volume over hardscape (aka Runoff Reduction Volume [RRV] as calculated in Montana Post- Construction Storwater BMP Manual - Equation 3-1) RRV = [P*Rv*A]/12 P = Water quality rainfall depth 0.50 inches Rv = Dimensionless runoff coefficient 0.67 0.05 + 0.9*I I = Percent impervious cover (decimal)0.68 decimal A = Entire drainage area 9.68 acres RRV = Runoff Reduction Volume 0.269 acre-ft RRV = Runoff Reduction Volume 11699 cubic feet POND 8C - DETENTION REQUIRED VOLUME 1. Calculate Area and Weighted C Factor (Post-Development) Contributing Area DA C Area (ft2)C * Area Park 8J 0.20 16304 3261 Residential - Dense (Reduced C) 8J 0.40 23902 9561 ROW - Local 8J 0.76 16953 12885 Residential - Low-Med 8K 0.35 15988 5596 ROW - Local 8K 0.76 8897 6762 Residential - Low-Med 8L 0.35 21604 7561 Residential - Dense (Reduced C) 8L 0.40 35468 14187 Park 8L 0.20 4800 960 OS 8L 0.20 3410 682 ROW - Local 8L 0.76 34076 25898 Residential - Low-Med 8M 0.35 38062 13322 ROW - Local 8M 0.76 13224 10051 Park 8M 0.20 6000 1200 Residential - Low-Med 8N 0.35 9242 3235 ROW - Local 8N 0.76 3580 2721 Total 251511 117880 A = Area (acres)5.77 C = Weighted C Factor 0.47 2. Pre-Development Conditions Pre-Development Drainage Area Name = EX 2 Pre-Development Drainage Area Size = 92.60 (acres) Pre Development Tc =96 (minutes) Pre-Development Runoff Rate (Total) =8.73 (cfs) Pre-Development Runoff Rate (Pond 8C) = 1.26 (cfs) Pre-Development Runoff Rate (Pond 8A) =1.88 (cfs) Pre-Development Runoff Rate (Pond 8B) =4.94 (cfs) Pre-Development Runoff Rate (Pond 9) =0.65 (cfs) Pre-Development Runoff Rate (Total) =8.73 (cfs) 5. Calculate Required Pond Volume Total Area (acres) =5.77 acres Weighted C =0.47 Discharge Rate (cfs) =1.26 cfs (Equal to Pre-Development Runoff Rate) Duration(min)Duration(hrs)Intensity (in/hr)Qin (cfs)Runoff Volume Release Volume Required Storage (ft3) 15 0.25 2 4 3,838 227 3,611 16 0.27 2 4 3,926 302 3,623 17 0.28 1 4 4,010 378 3,632 18 0.30 1 4 4,091 454 3,637 19 0.32 1 4 4,169 529 3,640 20 0.33 1 4 4,245 605 3,640 21 0.35 1 3 4,318 680 3,637 22 0.37 1 3 4,389 756 3,633 23 0.38 1 3 4,457 832 3,626 24 0.40 1 3 4,524 907 3,617 PROVIDED VOLUME (ft3)3,925 OUTLET STRUCTURE SLOT Q=CLH3/2 Q = Discharge (cfs)1.26 C = Weir Coefficient 3.33 (per COB Design Standards) H = Head (ft)1.5 L = Horizontal Length (ft)0.21 L = Slot Width (inches)2.5 Check the half inch requirement (per DSSP II.A.4) 1. Determine Area of Hardscape within Drainage Basin Contributing Area Area (ft 2 ) Hardscape 90,103 2. Calculate 1/2" runoff volume over hardscape (aka Runoff Reduction Volume [RRV] as calculated in Montana Post- Construction Storwater BMP Manual - Equation 3-1) RRV = [P*Rv*A]/12 P = Water quality rainfall depth 0.50 inches Rv = Dimensionless runoff coefficient 0.37 0.05 + 0.9*I I = Percent impervious cover (decimal)0.36 decimal A = Entire drainage area 5.77 acres RRV = Runoff Reduction Volume 0.090 acre-ft RRV = Runoff Reduction Volume 3903 cubic feet POND 8B - DETENTION REQUIRED VOLUME 1. Calculate Area and Weighted C Factor (Post-Development) Contributing Area DA C Area (ft2 )C * Area ROW - Angled 8B 0.93 31758 29535 Commercial 8B 0.95 0 0 ROW - Local 8B 0.76 8489 6452 ROW - Local 8D 0.76 28957 22007 Park 8B 0.20 0 0 Residential - Dense (Reduced C)8B 0.40 0 0 Residential - Low-Med 8D 0.35 104870 36704 ROW - Local 8G 0.76 16169 12288 ROW - Alley 8D 0.80 10487 8390 Residential - Low-Med 8G 0.35 48000 16800 ROW - Local 8I 0.76 2548 1937 OS 8I 0.20 4469 894 Total 255747 135007 A = Area (acres)5.87 C = Weighted C Factor 0.53 2. Pre-Development Conditions Pre-Development Drainage Area Name = EX 2 Pre-Development Drainage Area Size = 92.60 (acres) Pre Development Tc =96 (minutes) Pre-Development Runoff Rate (Total) =8.73 (cfs) Pre-Development Runoff Rate (Pond 8B) =4.94 (cfs) Pre-Development Runoff Rate (Pond 8C)=1.26 (cfs) Pre-Development Runoff Rate (Pond 8A)=1.88 (cfs) Pre-Development Runoff Rate (Pond 9) =0.65 (cfs) Pre-Development Runoff Rate (Total) =8.73 (cfs) 5. Calculate Required Pond Volume Total Area (acres) =5.87 acres Weighted C =0.53 Discharge Rate (cfs) =4.94 cfs (Equal to Pre-Development Runoff Rate) Duration(min)Duration(hrs)Intensity (in/hr)Qin (cfs)Runoff Volume Release Volume Required Storage (ft3) 3 0.05 4 25 4,448 0 4,448 4 0.07 4 20 4,919 0 4,919 5 0.08 3 18 5,318 296 5,022 6 0.10 3 16 5,669 593 5,076 7 0.12 3 14 5,983 889 5,094 8 0.13 2 13 6,269 1,186 5,084 9 0.15 2 12 6,533 1,482 5,051 10 0.17 2 11 6,778 1,778 5,000 11 0.18 2 11 7,008 2,075 4,934 12 0.20 2 10 7,225 2,371 4,854 PROVIDED VOLUME (ft3)5,095 OUTLET STRUCTURE SLOT Q=CLH3/2 Q = Discharge (cfs)4.94 C = Weir Coefficient 3.33 (per COB Design Standards) H = Head (ft)1.5 L = Horizontal Length (ft)0.81 L = Slot Width (inches)9.7 Check the half inch requirement (per DSSP II.A.4) 1. Determine Area of Hardscape within Drainage Basin Contributing Area Area (ft2 ) Hardscape 111,810 1/2" of Runoff for Block 17, Block 12 will be handled on each site during the site plan process 2. Calculate 1/2" runoff volume over hardscape (aka Runoff Reduction Volume [RRV] as calculated in Montana Post- Construction Storwater BMP Manual - Equation 3-1) RRV = [P*Rv*A]/12 P = Water quality rainfall depth 0.50 inches Rv = Dimensionless runoff coefficient 0.44 0.05 + 0.9*I I = Percent impervious cover (decimal)0.437 decimal A = Entire drainage area 5.87 acres RRV = Runoff Reduction Volume 0.108 acre-ft RRV = Runoff Reduction Volume 4726 cubic feet POND 8A - DETENTION REQUIRED VOLUME 1. Calculate Area and Weighted C Factor (Post-Development) Contributing Area DA C Area (ft 2)C * Area ROW - Local 8A 0.76 36398 27754 ROW - Angled 8A 0.93 20802 19346 Residential - Dense (Reduced C)8A 0.40 99407 39763 Commercial 8A 0.95 43975 41776 Park 8A 0.20 12172 2434 OS 8A 0.20 13111 2622 ROW - Local 8C 0.76 11853 9008 Residential - Low-Med 8C 0.35 25880 9058 ROW - Local 8E 0.76 12430 9447 Residential - Low-Med 8E 0.35 22158 7755 Residential - Low-Med 8F 0.35 19747 6911 ROW - Local 8F 0.76 6521 4956 ROW - Local 8H 0.76 2300 1748 OS 8H 0.20 4500 900 Total 331254 183479 A = Area (acres)7.60 C = Weighted C Factor 0.55 2. Pre-Development Conditions Pre-Development Drainage Area Name = EX 2 Pre-Development Drainage Area Size = 92.60 (acres) Pre Development Tc =96 (minutes) Pre-Development Runoff Rate (Total) =8.73 (cfs) Pre-Development Runoff Rate (Pond 8A) =1.88 (cfs) Pre-Development Runoff Rate (Pond 8C) =1.26 (cfs) Pre-Development Runoff Rate (Pond 8B) =4.94 (cfs) Pre-Development Runoff Rate (Pond 9) =0.65 (cfs) Pre-Development Runoff Rate (Total) =8.73 (cfs) 5. Calculate Required Pond Volume Total Area (acres) =7.60 acres Weighted C =0.55 Discharge Rate (cfs) =1.88 cfs (Equal to Pre-Development Runoff Rate) Duration(min)Duration(hrs)Intensity (in/hr)Qin (cfs)Runoff Volume Release Volume Required Storage (ft3) 17 0.28 1 6 6,241 1,241 5,001 18 0.30 1 6 6,368 1,354 5,014 19 0.32 1 6 6,489 1,466 5,023 20 0.33 1 6 6,607 1,579 5,028 21 0.35 1 5 6,721 1,692 5,029 22 0.37 1 5 6,831 1,805 5,026 23 0.38 1 5 6,938 1,918 5,020 24 0.40 1 5 7,042 2,030 5,012 25 0.42 1 5 7,143 2,143 5,000 26 0.43 1 5 7,242 2,256 4,986 PROVIDED VOLUME (ft3)5,130 OUTLET STRUCTURE SLOT Q=CLH3/2 Q = Discharge (cfs)1.88 C = Weir Coefficient 3.33 (per COB Design Standards) H = Head (ft)1.5 L = Horizontal Length (ft)0.31 L = Slot Width (inches)3.7 Check the half inch requirement (per DSSP II.A.4) 1. Determine Area of Hardscape within Drainage Basin Contributing Area Area (ft 2 ) Hardscape 156,304 2. Calculate 1/2" runoff volume over hardscape (aka Runoff Reduction Volume [RRV] as calculated in Montana Post- Construction Storwater BMP Manual - Equation 3-1) RRV = [P*Rv*A]/12 P = Water quality rainfall depth 0.50 inches Rv = Dimensionless runoff coefficient 0.475 0.05 + 0.9*I I = Percent impervious cover (decimal)0.472 decimal A = Entire drainage area 7.60 acres RRV = Runoff Reduction Volume 0.150 acre-ft RRV = Runoff Reduction Volume 4586 cubic feet POND 9 - DETENTION REQUIRED VOLUME 1. Calculate Area and Weighted C Factor (Post-Development) Contributing Area DA C Area (ft 2)C * Area ROW - Local 9A 0.76 14613 11106 Residential - Dense 9A 0.75 84215 63161 ROW - Local 9B 0.76 46828 35590 Park 9B 0.20 20901 4180 Residential - Dense 9B 0.75 153570 115178 ROW - Local 9C 0.76 22307 16953 Commercial 9C 0.95 26505 25180 Residential - Dense (Reduced C) 9C 0.40 45055 18022 ROW - Local 9D 0.76 12697 9649 Residential - Dense 9D 0.40 11619 4647 OS 9D 0.20 3357 671 ROW - Local 9E 0.76 21527 16360 Residential - Dense 9E 0.75 102610 76958 ROW - Local 9F 0.76 7859 5973 ROW - Local 9G 0.76 9046 6875 OS 9G 0.20 13120 2624 Park 9G 0.20 4251 850 Residential - Dense 9G 0.75 35478 26609 ROW - Local 9H 0.76 17977 13662 Residential - Low-Med 9H 0.35 20009 7003 ROW - Local 9I 0.76 11917 9057 ROW - Collector 9I 0.70 35815 25070 Residential - Dense 9I 0.75 46397 34798 ROW - Collector 9J 0.70 41138 28797 ROW - Local 9K 0.76 5714 4343 Residential - Low-Med 9K 0.35 12487 4370 Residential - Dense 9L 0.75 103406 77554 OS 9L 0.20 50963 10193 Total 981380 655434 A = Area (acres)22.53 C = Weighted C Factor 0.67 2. Pre-Development Conditions Pre-Development Drainage Area Name = EX 2 Pre-Development Drainage Area Size = 92.60 (acres) Pre Development Tc =96 (minutes) Pre-Development Runoff Rate (Total) =8.73 (cfs) Pre-Development Runoff Rate (Pond 8A) =1.88 (cfs) Pre-Development Runoff Rate (Pond 8B) =4.94 (cfs) Pre-Development Runoff Rate (Pond 8C) =1.26 Pre-Development Runoff Rate (Pond 9) =0.65 (cfs) Pre-Development Runoff Rate (Total) =8.73 (cfs) 5. Calculate Required Pond Volume Total Area (acres) =22.53 acres Weighted C =0.67 Discharge Rate (cfs) =0.65 cfs (Equal to Pre-Development Runoff Rate) Duration(min)Duration(hrs)Intensity (in/hr)Qin (cfs)Runoff Volume Release Volume Required Storage (ft3) 751 12.52 0.12 1.86 83,955 28,392 55,563 752 12.53 0.12 1.86 83,994 28,431 55,563 753 12.55 0.12 1.86 84,033 28,470 55,563 754 12.57 0.12 1.86 84,072 28,509 55,563 755 12.58 0.12 1.86 84,111 28,548 55,563 756 12.60 0.12 1.86 84,150 28,587 55,563 757 12.62 0.12 1.85 84,189 28,626 55,563 758 12.63 0.12 1.85 84,228 28,665 55,563 759 12.65 0.12 1.85 84,267 28,704 55,563 760 12.67 0.12 1.85 84,305 28,743 55,562 PROVIDED VOLUME (ft3)57,340 OUTLET STRUCTURE SLOT Q=CLH3/2 Q = Discharge (cfs)0.65 C = Weir Coefficient 3.33 (per COB Design Standards) H = Head (ft)0.75 L = Horizontal Length (ft)0.30 L = Slot Width (inches)3.6 Check the half inch requirement (per DSSP II.A.4) 1. Determine Area of Hardscape within Drainage Basin Contributing Area Area (ft 2 ) Hardscape 612,210 2. Calculate 1/2" runoff volume over hardscape (aka Runoff Reduction Volume [RRV] as calculated in Montana Post- Construction Storwater BMP Manual - Equation 3-1) RRV = [P*Rv*A]/12 P = Water quality rainfall depth 0.50 inches Rv = Dimensionless runoff coefficient 0.61 0.05 + 0.9*I I = Percent impervious cover (decimal)0.62 decimal A = Entire drainage area 22.53 acres RRV = Runoff Reduction Volume 0.574 acre-ft RRV = Runoff Reduction Volume 25002 cubic feet APPENDIX E Groundwater Monitoring Results Project Engineer: Project: South Bozeman, Gallatin County, MT Well Information:bgs = below ground surface ags = above ground surface MW-1 MW-2 MW-3 MW-4 MW-5 MW-6 MW-7 MW-8 MW-9 MW-10 MW-11 MW-12 MW-13 MW-14 MW-15 MW-16 MW-17 MW-18 MW-19 MW-20 3.83 3.00 3.08 3.67 1.50 2.42 2.08 3.58 2.92 2.92 3.83 2.92 3.92 3.58 4.08 3.00 3.92 3.50 3.58 2.92 Groundwater Information: MW-1 MW-2 MW-3 MW-4 MW-5 MW-6 MW-7 MW-8 MW-9 MW-10 MW-11 MW-12 MW-13 MW-14 MW-15 MW-16 MW-17 MW-18 MW-19 MW-20 3.34 3.05 3.02 2.78 3.45 1.58 4.24 4.27 2.55 4.13 3.99 4.36 2.25 2.27 2.26 5.50 2.71 2.20 2.97 2.38 3.47 3.18 3.11 2.85 3.49 1.50 4.42 4.42 2.64 4.34 4.31 4.78 2.50 2.32 2.60 6.10 2.85 2.42 3.40 2.77 3.57 3.23 3.13 2.94 4.10 1.64 4.53 4.53 2.67 4.45 4.36 4.90 2.54 2.39 2.65 6.21 2.92 2.74 3.74 2.96 3.75 3.42 3.26 3.18 3.74 1.88 4.72 4.70 2.80 4.59 4.50 5.16 2.84 2.54 2.84 6.32 3.18 3.14 4.07 3.19 3.78 3.63 3.36 3.35 3.81 1.94 4.90 4.98 2.99 4.86 4.56 5.31 3.16 2.83 3.23 DRY 3.79 3.68 4.31 3.49 3.76 3.65 3.41 3.43 3.76 1.91 4.94 5.11 3.09 4.98 4.68 5.48 3.25 2.79 3.30 DRY 4.17 3.91 4.51 3.56 3.94 3.82 3.52 3.45 3.83 2.00 4.90 5.23 3.27 5.08 4.82 5.60 3.42 2.88 3.37 DRY 4.29 4.05 4.67 3.59 3.90 3.68 3.38 3.31 3.75 1.94 4.85 4.93 3.08 5.02 4.86 5.66 3.37 2.88 3.20 DRY 4.22 4.11 4.80 3.48 4.00 3.87 3.55 3.60 4.01 2.24 5.11 5.23 3.44 5.18 4.82 5.65 3.54 3.13 3.46 DRY 4.59 4.31 4.87 3.80 4.09 3.52 3.34 3.33 3.81 2.09 5.06 5.03 3.11 4.99 5.42 5.08 3.34 2.89 3.37 DRY 4.59 4.41 4.47 3.60 4.14 4.09 3.69 3.72 3.92 2.34 5.24 5.42 3.69 5.39 4.95 5.78 3.73 3.34 3.69 DRY 4.87 4.65 5.03 3.89 4.16 4.38 4.13 4.01 4.12 2.49 5.43 5.70 4.06 5.99 5.27 6.24 4.20 3.79 3.99 DRY 5.29 5.19 5.63 4.07 ICE 2.50 2.49 2.03 ICE 0.93 3.43 3.60 2.39 ICE 3.69 3.88 1.38 1.47 1.82 4.04 2.27 0.96 2.07 2.01 1.99 1.95 2.16 1.64 3.00 0.63 3.04 3.29 2.19 3.08 3.07 3.33 0.72 0.72 0.87 3.57 2.10 0.60 1.67 1.28 2.65 2.25 2.37 1.93 3.35 1.03 3.14 3.47 2.29 3.26 3.29 3.60 1.18 1.62 1.57 3.60 2.30 1.20 2.19 1.45 2.94 2.50 2.53 2.17 1.90 1.54 3.32 3.68 2.33 3.53 3.63 3.83 1.56 1.53 1.86 4.13 2.40 1.45 2.47 1.86 3.27 2.97 2.84 2.64 2.35 1.42 3.72 4.30 2.48 3.95 3.92 4.23 2.00 1.67 2.13 4.52 2.68 2.04 3.07 2.38 3.47 3.20 3.00 2.85 2.50 1.52 3.94 4.38 2.59 4.23 4.17 4.61 2.30 2.29 2.42 4.97 2.81 2.55 3.42 2.70 3.57 3.28 3.10 2.98 2.60 1.68 4.13 4.52 2.65 4.39 4.37 4.88 2.53 2.35 2.64 DRY 2.91 2.92 3.85 2.93 3.68 3.38 3.21 3.10 2.70 1.74 4.29 4.68 2.70 4.54 4.57 5.10 2.73 2.43 2.81 DRY 3.12 3.30 4.13 3.17 3.79 3.51 3.32 3.20 2.66 1.89 4.51 4.79 2.81 4.71 4.74 5.32 2.93 2.60 2.97 DRY 3.47 3.56 4.37 3.33 3.92 3.63 3.51 3.38 2.79 1.95 4.79 4.90 2.92 4.89 4.78 5.49 3.08 2.63 3.08 DRY 3.73 4.09 4.57 3.59 5.15.20 4.10.20 4.17.20 4.24.20 5.1.20 5.8.20 Well ID Well Depth (feet-bgs) Top of Well (feet-ags) Ground Elevation 4.6.20 Date 5.10.19 6.10.19 6.17.19 6.20.19 6.28.19 7.12.19 7.26.19 8.9.19 Monitor Well Data Depth to Ground Water (feet-bgs) Project Number: 190390 South Bozeman Groundwater Monitoring Project Location: 8.23.19 3.24.20 5.20.19 5.24.19 5.31.19 5.22.205.29.20