Loading...
HomeMy WebLinkAbout012 Stormwater Management Design Report - TPS STORMWATER MANAGEMENT DESIGN REPORT FOR: TOWNEPLACE SUITES LOT 1A EASTLAKE PROFESSIONAL CENTER SUBDIVISION BOZEMAN, MT Prepared By: Madison Engineering 895 Technology Drive, Suite 203 Bozeman, MT 59718 (406) 586-0262 January 2023 Page 1 of 2 TOWNEPLACE SUITES LOT 1A OF EASTLAKE PROFESSISOANL CENTER SUBDIVSION STORMWATER DESIGN REPORT A. Introduction This design report will give an overview of the stormwater system for the proposed 107 room Towneplace Suites located on North 27th and Honor Lane in Bozeman, Montana. The proposed commercial development will be constructed on B2 (Community Business District) zoned property with associated on-site drive aisles, driveways, parking, pedestrian walkways and landscaping. No off-site improvements are required. The proposed storm water management system consists of overland sheet flow, catch basin/curb inlets, curb & gutter and piping that will direct stormwater to an on-site RTank retention/infiltration basin to serve the site. Off-site discharge is not proposed. Roof run-off is collected via roof drain piping and directed to the stormwater basin as well. The infiltration basin will be excavated to native gravels to permit maximum infiltration. The following references were used in the preparation of this report: a. COB Design Standards and Specifications Policy, 2004. Addendum #7 b. COB Modifications to Montana Public Works Standard Specifications (MPWSS) The proposed drainage and grading plan are included in Appendix A of this report. B. Native Soils and Groundwater Data Soils on the subject property are typical for the area and are detailed in Appendix D – On-Site Exploration Logs from section of the Geotechnical Report prepared by TD & H Engineering. Groundwater depths were observed and recorded as part of the Geotechnical Investigation. Groundwater depth was measured in monitoring well #10 at approximately 8 feet below the existing ground surface. This test pit is located near the proposed underground stormwater basin. C. Conveyance Capacity The proposed private stormwater collection system was designed to convey the 25-year storm event per the City of Bozeman standards. The conveyance structures include piping that directs stormwater run-off to the on-site infiltration basins. Storm sewer piping and area drains/curb inlets are proposed to collect and convey the stormwater run-off from the basins to the RTank retention/infiltration basin. Stormwater run-off and piping calculations are included in Appendix C of this report. Page 2 of 2 D. Stormwater Retention/Infiltration Basin Calculation Subsurface RTank infiltration chambers are proposed for this project. The stormwater runoff from the site is proposed to be conveyed to the on-site RTank retention/infiltration basin and ultimately infiltrate into native gravels. The retention storage volume was sized based on the 10-year 2-hour design rainfall frequency in accordance with the COB design standards. The rational method was used to determine post- development stormwater flows. A runoff coefficient C of 0.90 was used for impervious areas and a C value of 0.20 was used for landscaped areas. The calculations for all RTank stormwater storage facility is included in Appendix B of this report. The proposed stormwater facility reduces the post-development off-site runoff rate to nearly zero. All impervious surface runoff is conveyed to the infiltration retention systems and then infiltrates into the ground. F. Stormwater Facility Maintenance The proposed storm drainage facilities will be privately operated and maintained by the property owner of the on-site development. Included in Appendix E is a proposed maintenance program for the stormwater collection and infiltration systems as well as the O&M Manual for the RTank system. Appendix A. Grading & Drainage Design B. RTank Basin Calculations C. Stormwater Run-off and Piping Calculations D. On-Site Exploration Logs E. O&M Manual APPENDIX Appendix A Grading & Drainage Design Appendix B Tank Basin Calculations Appendix B TownePlace Suites Rtank Basin Sizing Calculations Design Rainfall Freq. 10 year - 2 Hour Event IDF coefficient a 0.64 IDF coefficient b IDF coefficient n 0.65 Post-development Conditions Square feet Acres C Impervious 77,410 1.78 0.90 Landscaped 13,932 0.32 0.20 Total area 91,342 2.10 Composite C 0.79 Retention Basin Calculation: Q = CIA C = 0.79 (post-development) I = 0.41 in/hr (10-yr, 2-hr storm) A = 2.10 acres Qpost = 0.68 cfs Required retention storage (ft3) =4,885 ft3 (10-yr, 2-hr storm) R-Tank Volume Calculation Length 28.15 inches 2.35 ft Width 15.75 inches 1.31 ft Height (Double) 33.86 inches 2.82 ft # of Modules Basin Area Horizontally Length 56.30 sf 24 Width 11.81 sf 9 Area 665.04 sf 216 per layer Height (ft) # of Modules Double 2.82 1 Single 1.44 1 Mini 0.79 1 R-Tank Module Height 5.05 ft 1 Double R-Tank LD Volume 3360 sf (Gross Volume) R-Tank Efficieny 95% Total R-Tank HD Volume 3,192 ft3 (Net Volume) Rtank Module Size Gravel Volume Calculation Perimeter Gravel Width 3 ft Perimeter Gravel Depth Top 0.5 ft Bottom 1.3 ft Total 1.8 ft Top and Bottom Rtank Basin Length 56.30 62.30 ft Width 11.81 17.81 ft Area 1,109.7 ft2 Volume 1,997.5 ft3 @40% =799.0 ft3 Sides Height Gross Volume 5,606.9 Less RTank Volume 3,360.1 Net Basin Volume 2,246.7 ft3 @40%898.7 ft3 Gravel Volume 1,697.7 ft3 Total Basin Volume 4889.8 ft3 Finish Grade 4670.00 ft Top of Gravel 4669.00 ft Top of Rtank 4668.50 ft Bottom of Rtank 4663.45 ft Bottom of Gravel 4662.15 ft Appendix C Stormwater Run-off and Piping Calculations Appendix C TownePlace Suites Stormwater Basin Runoff Calculations Design Rainfall Freq. 25 year IDF coefficient a 0.78 IDF coefficient b IDF coefficient n 0.64 Basin A Post-development Calculations C Areas (ft2):Landscape 994 0.20 Impervious 9,811 0.90 Total: 10,805 total area: 0.25 acres composite C: 0.84 Overland tc average slope: 2.5 percent travel distance: 100 feet tc:4 minutes Total tc:4 minutes intensity at tc (fig 23):4.69 in/hr Basin A post-devel peak runoff: 0.97 cfs Pipe A 4.4 cfs Basin B Post-development Calculations C Areas (ft2):Landscape 0.20 Impervious 8,499 0.90 Total: 8,499 total area: 0.20 acres composite C: 0.90 Overland tcaverage slope: 3 percent travel distance: 175 feet tc:3 minutes Total tc:3 minutes intensity at tc (fig 23):4.87 in/hr Basin B post-devel peak runoff: 0.86 cfs Cummulative Basin A & B post-devel peak runoff: 1.83 cfs Pipe B 2.0 cfs Storm Runoff Calculation.xls Appendix C TownePlace Suites Stormwater Basin Runoff Calculations Basin E (Roof) Post-development Calculations C Areas (ft2):Landscape 5,789 0.20 Impervious 22,887 0.90 Total: 28,676 total area: 0.66 acres composite C: 0.76 Overland tc average slope: 3 percent travel distance: 175 feet tc:6 minutes Total tc:6 minutes intensity at tc (fig 23):3.46 in/hr Basin E post-devel peak runoff: 1.73 cfs Basin E post-devel peak runoff: 0.86 cfs (1/2 of roof area) Pipe E 0.9 cfs Basin C Post-development Calculations C Areas (ft2):Landscape 1,360 0.20 Impervious 13,326 0.90 Total: 14,686 total area: 0.34 acres composite C: 0.84 Overland tc average slope: 3 percent travel distance: 175 feet tc:5 minutes Total tc:5 minutes intensity at tc (fig 23):4.07 in/hr Basin C post-devel peak runoff: 1.15 cfs Cummulative Basin A, B, C & 1/2E post-devel peak runoff: 4.81 cfs Pipe C 8.9 cfs Basin D Post-development Calculations C Areas (ft2):Landscape 5,789 0.20 Impervious 22,887 0.90 Total: 28,676 total area: 0.66 acres composite C: 0.76 Overland tc average slope: 3 percent travel distance: 175 feet tc:6 minutes Total tc:6 minutes intensity at tc (fig 23):3.46 in/hr Basin D post-devel peak runoff: 1.73 cfs Cummulative Basin A, B, C, D & 1/2E post-devel peak runoff: 5.56 cfs Pipe C 8.9 cfs Storm Runoff Calculation.xls TOWNEPLACE SUITES Pipe A 12" pipe from Basin A CIRCULAR CHANNEL Manning's Eqn.1.486 A R2/3 S1/2 n Diameter,do (in) =12.0 Enter Value Diameter,do (ft) =1.00 Units =1.486 n =0.013 Slope, S (ft/ft)0.015 Depth, y (ft) Theta (rad) Area, A (ft 2) Wetted Perimeter, P (ft) Hydraulic Radius, R (ft) Top Width, T (ft) Hydraulic Depth, D (ft) Section Factor, Z (ft5/2) Q (cfs) Q (gpm) Q (gpd - 8 hour day) V (ft/s) Energy, E = V2/2g (ft) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.0 0.0 0.0 0.0 0.00 0.05 0.90 0.01 0.45 0.03 0.44 0.03 0.00 0.0 9.4 4514.0 1.4 0.03 0.10 1.29 0.04 0.64 0.06 0.60 0.07 0.01 0.1 40.9 19625.3 2.2 0.08 0.15 1.59 0.07 0.80 0.09 0.71 0.10 0.02 0.2 95.2 45693.2 2.9 0.13 0.20 1.85 0.11 0.93 0.12 0.80 0.14 0.04 0.4 171.5 82317.8 3.4 0.18 0.25 2.09 0.15 1.05 0.15 0.87 0.18 0.06 0.6 268.3 128764.0 3.9 0.24 0.30 2.32 0.20 1.16 0.17 0.92 0.22 0.09 0.9 383.5 184083.0 4.3 0.29 0.35 2.53 0.24 1.27 0.19 0.95 0.26 0.12 1.1 514.9 247165.7 4.7 0.34 0.40 2.74 0.29 1.37 0.21 0.98 0.30 0.16 1.5 659.9 316771.3 5.0 0.39 0.45 2.94 0.34 1.47 0.23 0.99 0.34 0.20 1.8 815.7 391541.3 5.3 0.44 0.50 3.14 0.39 1.57 0.25 1.00 0.39 0.25 2.2 979.2 470004.2 5.6 0.48 0.55 3.34 0.44 1.67 0.26 0.99 0.44 0.30 2.6 1147.0 550573.2 5.8 0.52 0.60 3.54 0.49 1.77 0.28 0.98 0.50 0.35 2.9 1315.7 631535.4 6.0 0.55 0.65 3.75 0.54 1.88 0.29 0.95 0.57 0.41 3.3 1481.3 711030.3 6.1 0.58 0.70 3.96 0.59 1.98 0.30 0.92 0.64 0.47 3.7 1639.6 787010.4 6.2 0.60 0.75 4.19 0.63 2.09 0.30 0.87 0.73 0.54 4.0 1785.8 857172.7 6.3 0.62 0.80 4.43 0.67 2.21 0.30 0.80 0.84 0.62 4.3 1914.2 918827.1 6.3 0.62 0.85 4.69 0.71 2.35 0.30 0.71 1.00 0.71 4.5 2018.0 968622.6 6.3 0.62 0.90 5.00 0.74 2.50 0.30 0.60 1.24 0.83 4.7 2087.2 1001858.4 6.2 0.61 0.95 5.38 0.77 2.69 0.29 0.44 1.77 1.02 4.7 2104.3 1010052.7 6.1 0.57 1.00 6.28 0.79 3.14 0.25 0.00 4.4 1959.0 940326.2 5.6 0.48 Q = 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 0.00 0.20 0.40 0.60 0.80 1.00 1.20 Depth (ft) Q (CFS) V (ft/s) E (ft)ydoT THETA TOWNEPLACE SUITES Pipe B 12" pipe from Basin B CIRCULAR CHANNEL Manning's Eqn.1.486 A R2/3 S1/2 n Diameter,do (in) =12.0 Enter Value Diameter,do (ft) =1.00 Units =1.486 n =0.013 Slope, S (ft/ft)0.003 Depth, y (ft) Theta (rad) Area, A (ft 2) Wetted Perimeter, P (ft) Hydraulic Radius, R (ft) Top Width, T (ft) Hydraulic Depth, D (ft) Section Factor, Z (ft5/2) Q (cfs) Q (gpm) Q (gpd - 8 hour day) V (ft/s) Energy, E = V2/2g (ft) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.0 0.0 0.0 0.0 0.00 0.05 0.90 0.01 0.45 0.03 0.44 0.03 0.00 0.0 4.2 2018.7 0.6 0.01 0.10 1.29 0.04 0.64 0.06 0.60 0.07 0.01 0.0 18.3 8776.7 1.0 0.02 0.15 1.59 0.07 0.80 0.09 0.71 0.10 0.02 0.1 42.6 20434.6 1.3 0.03 0.20 1.85 0.11 0.93 0.12 0.80 0.14 0.04 0.2 76.7 36813.6 1.5 0.04 0.25 2.09 0.15 1.05 0.15 0.87 0.18 0.06 0.3 120.0 57585.0 1.7 0.05 0.30 2.32 0.20 1.16 0.17 0.92 0.22 0.09 0.4 171.5 82324.4 1.9 0.06 0.35 2.53 0.24 1.27 0.19 0.95 0.26 0.12 0.5 230.3 110535.8 2.1 0.07 0.40 2.74 0.29 1.37 0.21 0.98 0.30 0.16 0.7 295.1 141664.4 2.2 0.08 0.45 2.94 0.34 1.47 0.23 0.99 0.34 0.20 0.8 364.8 175102.6 2.4 0.09 0.50 3.14 0.39 1.57 0.25 1.00 0.39 0.25 1.0 437.9 210192.3 2.5 0.10 0.55 3.34 0.44 1.67 0.26 0.99 0.44 0.30 1.1 513.0 246223.8 2.6 0.10 0.60 3.54 0.49 1.77 0.28 0.98 0.50 0.35 1.3 588.4 282431.2 2.7 0.11 0.65 3.75 0.54 1.88 0.29 0.95 0.57 0.41 1.5 662.5 317982.4 2.7 0.12 0.70 3.96 0.59 1.98 0.30 0.92 0.64 0.47 1.6 733.3 351961.8 2.8 0.12 0.75 4.19 0.63 2.09 0.30 0.87 0.73 0.54 1.8 798.6 383339.3 2.8 0.12 0.80 4.43 0.67 2.21 0.30 0.80 0.84 0.62 1.9 856.1 410912.0 2.8 0.12 0.85 4.69 0.71 2.35 0.30 0.71 1.00 0.71 2.0 902.5 433181.2 2.8 0.12 0.90 5.00 0.74 2.50 0.30 0.60 1.24 0.83 2.1 933.4 448044.7 2.8 0.12 0.95 5.38 0.77 2.69 0.29 0.44 1.77 1.02 2.1 941.1 451709.3 2.7 0.11 1.00 6.28 0.79 3.14 0.25 0.00 2.0 876.1 420526.7 2.5 0.10 Q = 0.0 0.5 1.0 1.5 2.0 2.5 3.0 0.00 0.20 0.40 0.60 0.80 1.00 1.20 Depth (ft) Q (CFS) V (ft/s) E (ft)ydoT THETA TOWNEPLACE SUITES Pipe C 15" pipe from Basin A,B,C 1/2E CIRCULAR CHANNEL Manning's Eqn.1.486 A R2/3 S1/2 n Diameter,do (in) =15.0 Enter Value Diameter,do (ft) =1.25 Units =1.486 n =0.013 Slope, S (ft/ft)0.019 Depth, y (ft) Theta (rad) Area, A (ft 2) Wetted Perimeter, P (ft) Hydraulic Radius, R (ft) Top Width, T (ft) Hydraulic Depth, D (ft) Section Factor, Z (ft5/2) Q (cfs) Q (gpm) Q (gpd - 8 hour day) V (ft/s) Energy, E = V2/2g (ft) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.0 0.0 0.0 0.0 0.00 0.06 0.90 0.02 0.56 0.04 0.54 0.04 0.00 0.0 19.2 9211.3 1.9 0.05 0.13 1.29 0.06 0.80 0.08 0.75 0.09 0.02 0.2 83.4 40047.4 2.9 0.13 0.19 1.59 0.12 0.99 0.12 0.89 0.13 0.04 0.4 194.3 93241.5 3.7 0.22 0.25 1.85 0.17 1.16 0.15 1.00 0.17 0.07 0.8 350.0 167977.6 4.5 0.31 0.31 2.09 0.24 1.31 0.18 1.08 0.22 0.11 1.2 547.4 262755.9 5.1 0.40 0.38 2.32 0.31 1.45 0.21 1.15 0.27 0.16 1.7 782.6 375639.7 5.6 0.49 0.44 2.53 0.38 1.58 0.24 1.19 0.32 0.22 2.3 1050.8 504366.2 6.1 0.58 0.50 2.74 0.46 1.71 0.27 1.22 0.37 0.28 3.0 1346.7 646403.6 6.5 0.67 0.56 2.94 0.54 1.84 0.29 1.24 0.43 0.35 3.7 1664.5 798979.2 6.9 0.74 0.63 3.14 0.61 1.96 0.31 1.25 0.49 0.43 4.5 1998.1 959090.5 7.3 0.82 0.69 3.34 0.69 2.09 0.33 1.24 0.56 0.52 5.2 2340.6 1123499.6 7.5 0.88 0.75 3.54 0.77 2.22 0.35 1.22 0.63 0.61 6.0 2684.8 1288711.1 7.8 0.94 0.81 3.75 0.84 2.34 0.36 1.19 0.71 0.71 6.7 3022.8 1450928.3 8.0 0.99 0.88 3.96 0.92 2.48 0.37 1.15 0.80 0.82 7.5 3345.8 1605973.4 8.1 1.03 0.94 4.19 0.99 2.62 0.38 1.08 0.91 0.94 8.1 3644.1 1749146.5 8.2 1.05 1.00 4.43 1.05 2.77 0.38 1.00 1.05 1.08 8.7 3906.2 1874958.5 8.3 1.06 1.06 4.69 1.11 2.93 0.38 0.89 1.25 1.24 9.2 4117.9 1976571.3 8.3 1.06 1.13 5.00 1.16 3.12 0.37 0.75 1.55 1.45 9.5 4259.2 2044392.3 8.2 1.03 1.19 5.38 1.20 3.36 0.36 0.54 2.21 1.79 9.6 4294.0 2061113.5 7.9 0.98 1.25 6.28 1.23 3.93 0.31 0.00 8.9 3997.6 1918829.6 7.3 0.82 Q = 0.0 2.0 4.0 6.0 8.0 10.0 12.0 0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40 Depth (ft) Q (CFS) V (ft/s) E (ft)ydoT THETA TOWNEPLACE SUITES Pipe D 12 pipe from Basin A, B, C, D 1/2E CIRCULAR CHANNEL Manning's Eqn.1.486 A R2/3 S1/2 n Diameter,do (in) =12.0 Enter Value Diameter,do (ft) =1.00 Units =1.486 n =0.013 Slope, S (ft/ft)0.033 Depth, y (ft) Theta (rad) Area, A (ft 2) Wetted Perimeter, P (ft) Hydraulic Radius, R (ft) Top Width, T (ft) Hydraulic Depth, D (ft) Section Factor, Z (ft5/2) Q (cfs) Q (gpm) Q (gpd - 8 hour day) V (ft/s) Energy, E = V2/2g (ft) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.0 0.0 0.0 0.0 0.00 0.05 0.90 0.01 0.45 0.03 0.44 0.03 0.00 0.0 13.9 6695.4 2.1 0.07 0.10 1.29 0.04 0.64 0.06 0.60 0.07 0.01 0.1 60.6 29109.1 3.3 0.17 0.15 1.59 0.07 0.80 0.09 0.71 0.10 0.02 0.3 141.2 67774.0 4.3 0.28 0.20 1.85 0.11 0.93 0.12 0.80 0.14 0.04 0.6 254.4 122097.0 5.1 0.40 0.25 2.09 0.15 1.05 0.15 0.87 0.18 0.06 0.9 397.9 190987.9 5.8 0.52 0.30 2.32 0.20 1.16 0.17 0.92 0.22 0.09 1.3 568.8 273039.2 6.4 0.64 0.35 2.53 0.24 1.27 0.19 0.95 0.26 0.12 1.7 763.8 366605.9 6.9 0.75 0.40 2.74 0.29 1.37 0.21 0.98 0.30 0.16 2.2 978.8 469847.8 7.4 0.86 0.45 2.94 0.34 1.47 0.23 0.99 0.34 0.20 2.7 1209.9 580749.6 7.9 0.96 0.50 3.14 0.39 1.57 0.25 1.00 0.39 0.25 3.2 1452.4 697128.9 8.2 1.05 0.55 3.34 0.44 1.67 0.26 0.99 0.44 0.30 3.8 1701.3 816632.0 8.6 1.14 0.60 3.54 0.49 1.77 0.28 0.98 0.50 0.35 4.3 1951.5 936718.4 8.8 1.21 0.65 3.75 0.54 1.88 0.29 0.95 0.57 0.41 4.9 2197.1 1054628.3 9.1 1.27 0.70 3.96 0.59 1.98 0.30 0.92 0.64 0.47 5.4 2431.9 1167325.1 9.2 1.32 0.75 4.19 0.63 2.09 0.30 0.87 0.73 0.54 5.9 2648.7 1271392.5 9.3 1.35 0.80 4.43 0.67 2.21 0.30 0.80 0.84 0.62 6.3 2839.3 1362840.8 9.4 1.37 0.85 4.69 0.71 2.35 0.30 0.71 1.00 0.71 6.7 2993.1 1436699.5 9.4 1.36 0.90 5.00 0.74 2.50 0.30 0.60 1.24 0.83 6.9 3095.8 1485996.2 9.3 1.33 0.95 5.38 0.77 2.69 0.29 0.44 1.77 1.02 7.0 3121.1 1498150.2 9.0 1.26 1.00 6.28 0.79 3.14 0.25 0.00 6.5 2905.7 1394729.2 8.2 1.06 Q = 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 0.00 0.20 0.40 0.60 0.80 1.00 1.20 Depth (ft) Q (CFS) V (ft/s) E (ft)ydoT THETA TOWNEPLACE SUITES Pipe E 8 pipe from Roof CIRCULAR CHANNEL Manning's Eqn.1.486 A R2/3 S1/2 n Diameter,do (in) =8.0 Enter Value Diameter,do (ft) =0.67 Units =1.486 n =0.013 Slope, S (ft/ft)0.005 Depth, y (ft) Theta (rad) Area, A (ft 2) Wetted Perimeter, P (ft) Hydraulic Radius, R (ft) Top Width, T (ft) Hydraulic Depth, D (ft) Section Factor, Z (ft5/2) Q (cfs) Q (gpm) Q (gpd - 8 hour day) V (ft/s) Energy, E = V2/2g (ft) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.0 0.0 0.0 0.0 0.00 0.03 0.90 0.01 0.30 0.02 0.29 0.02 0.00 0.0 1.8 883.9 0.6 0.01 0.07 1.29 0.02 0.43 0.04 0.40 0.05 0.00 0.0 8.0 3843.1 1.0 0.01 0.10 1.59 0.03 0.53 0.06 0.48 0.07 0.01 0.0 18.6 8947.8 1.3 0.02 0.13 1.85 0.05 0.62 0.08 0.53 0.09 0.02 0.1 33.6 16119.7 1.5 0.04 0.17 2.09 0.07 0.70 0.10 0.58 0.12 0.02 0.1 52.5 25214.9 1.7 0.05 0.20 2.32 0.09 0.77 0.11 0.61 0.14 0.03 0.2 75.1 36047.6 1.9 0.06 0.23 2.53 0.11 0.84 0.13 0.64 0.17 0.05 0.2 100.8 48400.6 2.1 0.07 0.27 2.74 0.13 0.91 0.14 0.65 0.20 0.06 0.3 129.2 62031.0 2.2 0.08 0.30 2.94 0.15 0.98 0.16 0.66 0.23 0.07 0.4 159.7 76672.6 2.3 0.08 0.33 3.14 0.17 1.05 0.17 0.67 0.26 0.09 0.4 191.7 92037.4 2.4 0.09 0.37 3.34 0.20 1.11 0.18 0.66 0.30 0.11 0.5 224.6 107814.6 2.5 0.10 0.40 3.54 0.22 1.18 0.19 0.65 0.33 0.13 0.6 257.6 123668.9 2.6 0.11 0.43 3.75 0.24 1.25 0.19 0.64 0.38 0.15 0.6 290.1 139235.8 2.7 0.11 0.47 3.96 0.26 1.32 0.20 0.61 0.43 0.17 0.7 321.1 154114.4 2.7 0.12 0.50 4.19 0.28 1.40 0.20 0.58 0.49 0.20 0.8 349.7 167853.7 2.8 0.12 0.53 4.43 0.30 1.48 0.20 0.53 0.56 0.22 0.8 374.8 179927.1 2.8 0.12 0.57 4.69 0.32 1.56 0.20 0.48 0.66 0.26 0.9 395.2 189678.1 2.8 0.12 0.60 5.00 0.33 1.67 0.20 0.40 0.83 0.30 0.9 408.7 196186.5 2.8 0.12 0.63 5.38 0.34 1.79 0.19 0.29 1.18 0.37 0.9 412.1 197791.1 2.7 0.11 0.67 6.28 0.35 2.09 0.17 0.00 0.9 383.6 184137.1 2.4 0.09 Q = 0.0 0.5 1.0 1.5 2.0 2.5 3.0 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 Depth (ft) Q (CFS) V (ft/s) E (ft)ydoT THETA Appendix D On-Site Exploration Logs 0 1.5 3 4.5 6 7.5 9 10.5 TOPSOIL: Lean CLAY, appears firm to stiff, dark brown, moist Lean CLAY, appears firm to stiff, brown, moist Lean CLAY, appears soft to firm, light brown, moist Poorly-Graded GRAVEL with Sand, relatively dense, dark brown, moist, cobbles up to 6-inch Bottom of Test Pit 0.8 1.6 6.5 8.8 LEGEND LOG OF TEST PIT TP-8Atterberg Limits Field Moisture content North 27th Avenue Hotel Bozeman, MontanaGroundwater Level Grab/composite sample Logged by:Nic Couch, EI Excavated by:Earth Surgeons Komatsu PC170LCGNP = Granular and Nonplastic Note: The stratification lines represent approximate boundaries between soil types. Actual boundaries may be gradual or transitional. March 14, 2022 B22-015-001 Figure No. 9 SheetGRAPHICLOGSOIL DESCRIPTION SURFACE:Native Grasses SURFACE ELEVATION:Not Measured DEPTH (FT)GROUNDWATERSAMPLEDEPTH (FT)MOISTURE CONTENT 0 10 20 30 40 50 = MOISTURE CONTENT 1 of 1 0 1.5 3 4.5 6 7.5 9 10.5 TOPSOIL: Lean CLAY, appears firm to stiff, dark brown, moist Lean CLAY, appears firm to stiff, brown, moist Lean CLAY, appears soft to firm, light brown, moist Poorly-Graded GRAVEL with Sand, relatively dense, dark brown, moist, cobbles up to 6-inch Bottom of Test Pit 0.7 2.2 7.5 9.0 Ground water not encoun- tered G G LEGEND LOG OF TEST PIT TP-9Atterberg Limits Field Moisture content North 27th Avenue Hotel Bozeman, MontanaGroundwater Level Grab/composite sample Logged by:Nic Couch, EI Excavated by:Earth Surgeons Komatsu PC170LCGNP = Granular and Nonplastic Note: The stratification lines represent approximate boundaries between soil types. Actual boundaries may be gradual or transitional. March 14, 2022 B22-015-001 Figure No. 10 SheetGRAPHICLOGSOIL DESCRIPTION SURFACE:Unvegetated GRAVEL SURFACE ELEVATION:Not Measured DEPTH (FT)GROUNDWATERSAMPLEDEPTH (FT)MOISTURE CONTENT 0 10 20 30 40 50 = MOISTURE CONTENT 1 of 1 0 1.5 3 4.5 6 7.5 9 10.5 TOPSOIL: Lean CLAY, appears firm to stiff, dark brown, moist Lean CLAY, appears firm to stiff, brown, moist Lean CLAY, appears soft to firm, light brown, moist Poorly-Graded GRAVEL with Sand, relatively dense, dark brown, moist, cobbles up to 6-inch Bottom of Test Pit - Monitoring pipe set at 8.5 below original ground surface 0.9 1.8 7.0 9.5 G G LEGEND LOG OF TEST PIT TP-10Atterberg Limits Field Moisture content North 27th Avenue Hotel Bozeman, MontanaGroundwater Level Grab/composite sample Logged by:Nic Couch, EI Excavated by:Earth Surgeons Komatsu PC170LCGNP = Granular and Nonplastic Note: The stratification lines represent approximate boundaries between soil types. Actual boundaries may be gradual or transitional. March 14, 2022 B22-015-001 Figure No. 11 SheetGRAPHICLOGSOIL DESCRIPTION SURFACE:Unvegetated GRAVEL SURFACE ELEVATION:Not Measured DEPTH (FT)GROUNDWATERSAMPLEDEPTH (FT)MOISTURE CONTENT 0 10 20 30 40 50 = MOISTURE CONTENT 1 of 1 Appendix E O&M Manual G:\MADISON ENGINEERING\PROJECTS\2021\21-120 TPS-FFIS Site Plan\Storm\Report\STORMWATER MAINTENANCE PLAN.doc STORMWATER MAINTENANCE PLAN Towneplace Suites – Bozeman West Owner’s responsibility for routine inspection and maintenance 1. Keep the inlets of the facilities free of leaves, rocks, and other debris. 2. See that litter and other debris are removed from inlets, swales, and vegetated and paved areas. 3. Maintenance of the underground systems are as follows:  Minimum required maintenance includes a quarterly inspection during the first year of operation and a yearly inspection thereafter. Utilize inspection ports for inspections.  The inspection ports can be used to pump water into the system and re- suspend accumulated sediment so that is may be pumped out. Flush and pump as inspections deem necessary. 4. Property Owner to maintain and fund Operation and Maintenance of stormwater facilities. _______________________________ ______________, Property Owner Operation Your ACF R-Tank System has been designed to function in conjunction with the engineered drainage system on your site, the existing municipal infrastructure, and/or the existing soils and geography of the receiving watershed. Unless your site included certain unique and rare features, the operation of your R-Tank System will be driven by naturally occurring systems and will function autonomously. However, upholding a proper schedule of Inspection & Maintenance is critical to ensuring continued functionality and optimum performance of the system. Inspection Both the R-Tank and all stormwater pre-treatment features incorporated into your site must be inspected regularly. Inspection frequency for your system must be determined based on the contributing drainage area, but should never exceed one year between inspections (six months during the first year of operation). Inspections may be required more frequently for pre-treatment systems. You should refer to the manufacturer requirements for the proper inspection schedule. With the right equipment your inspection and measurements can be accomplished from the surface without physically entering any confined spaces. If your inspection does require confined space entry, you MUST follow all local/regional requirements as well as OSHA standards. R-Tank Systems may incorporate Inspection Ports, Maintenance Ports, and/or adjoining manholes. Each of these features are easily accessed by removing the lid at the surface. With the cover removed, a visual inspection can be performed to identify sediment deposits within the structure. Using a flashlight, ALL access points should be examined to complete a thorough inspection. Inspection Ports Usually located centrally in the R-Tank System, these perforated columns are designed to give the user a base-linesediment depth across the system floor. Maintenance Ports Usually located near the inlet and outlet connections, you’ll likely find deeper deposits of heavier sediments whencompared to the Inspection Ports. Manholes Most systems will include at least two manholes - one at the inlet and another at the outlet. There may be more than one location where stormwater enters the system, which would result in additional manholes to inspect. Bear in mind that these manholes often include a sump below the invert of the pipe connecting to the R-Tank. These sumps are designed to capture sediment before it reaches the R-Tank, and they should be kept clean to ensure they function properly. However, existence of sediment in the sump does NOT necessarily mean sediment has accumulated in the R-Tank. After inspecting the bottom of the structure, use a mirror on a pole (or some other device) to check for sediment or debris in the pipe connecting to the R-Tank. R-TANK OPERATION, INSPECTION& MAINTENANCE TECHNICALSTORMWATER MANAGEMENT For more information or design assistance for our products, contact techinfo@acfwest.com. If sediment or debris is observed in any of these structures, you should determine the depth of the material. This is typically accomplished with a stadia rod, but you should determine the best way to obtain the measurement. All observations and measurements should be recorded on an Inspection Log kept on file. We’ve included a form you can use at the end of this guideline. MaintenanceThe R-Tank System should be back-flushed once sediment accumulation has reached 6” or 15% of the total system height. Use the chart below as a guideline to determine the point at which maintenance is required on your system. Before any maintenance is performed on your system, be sure to plug the outlet pipe to prevent contamination of the adjacent systems. To back-flush the R-Tank, water is pumped into the system through the Maintenance Ports as rapidly as possible. Water should be pumped into ALL Maintenance Ports. The turbulent action of the water moving through the R-Tank will suspend sediments which may then be pumped out. If your system includes an Outlet Structure, this will be the ideal location to pump contaminated water out of the system. However, removal of back-flush water may be accomplished through the Maintenance Ports, as well. For systems with large footprints that would require extensive volumes of water to properly flush the system, you should consider performing your maintenance within 24 hours of a rain event. Stormwater entering the system will aid in the suspension of sediments and reduce the volume of water required to properly flush the system. Once removed, sediment-laden water may be captured for disposal or pumped through a DirtbagTM (if permitted by the locality). R-Tank Unit Height Max Sediment Dept Mini 9.5” 1.5” Single 17” 3” Double 34” 5” Triple 50” 6” Quad 67” 6” Pent 84” 6” R-TANK OPERATION INSPECTION & MAINTENANCE 15540 Woodinville-Redmond Rd Woodinville, Washington 98072 800-423-4567 www.acfwest.com Step-By-Step Inspection & Maintenance Routine 1)Inspection a.Inspection Port i.Remove Cap ii. Use flashlight to detect sediment deposits iii. If present, measure sediment depth with stadia rod iv. Record results on Maintenance Log v.Replace Cap b.Maintenance Port/s i.Remove Cap ii. Use flashlight to detect sediment deposits iii.If present, measure sediment depth with stadia rod iv.Record results on Maintenance Log v. Replace Cap vi.Repeat for ALL Maintenance Ports c.Adjacent Manholes i.Remove Cover ii. Use flashlight to detect sediment deposits iii. If present, measure sediment depth with stadia rod, accounting for depth of sump (if present) iv.Inspect pipes connecting to R-Tank v.Record results on Maintenance Log vi.Replace Cover vii.Repeat for ALL Manholes that connect to the R-Tank 2)Maintenance a.Plug system outlet to prevent discharge of back-flush water b.Determine best location to pump out back-flush water c.Remove Cap from Maintenance Port d.Pump water as rapidly as possible (without over-topping port) into system until at least 1” of water covers system bottom e.Replace Cap f.Repeat at ALL Maintenance Ports g.Pump out back-flush water to complete back-flushing h.Vacuum all adjacent structures and any other structures or stormwater pre-treatment systems that require attention i.Sediment-laden water may be captured for disposal or pumped through a DirtbagTM. j.Replace any remaining Caps or Covers k.Record the back-flushing event in your Maintenance Log with any relevant specifics R-Tank Maintenance LogCompany ResponsibleSite Name:___________________________________________ for Maintenance:__________________________________________________Location:_____________________________________________System Owner:______________________________________ Contact:__________________________________________________________________ Phone Number:__________________________________________________________For more information or design assistance for our products, contact techinfo@acfwest.com.