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HomeMy WebLinkAbout20 - Design Report - Allison Ph IV - Water WATER MAIN DESIGN REPORT FOR: ALLISON SUBDIVISION PHASE IV BOZEMAN, MT Prepared By: Madison Engineering 895 Technology Drive, Suite 203 Bozeman, MT 59718 (406) 586-0262 JUNE 2020 ALLISON SUBDIVISION PHASE IV WATER SYSTEM DESIGN REPORT A. General This design report will give an overview of the proposed water main extension for the 22.76 acre development of Allison Subdivision Phase IV (Section 24, Township 02S, Range 5E, Plat J- 608A) located at the intersection of Arnold Street and S. 11th Avenue in Bozeman. The report includes a description of the proposed water main and design parameters. The proposed improvements are anticipated to be constructed during the summer of 2020. Once the water main is constructed and approved, the main will become a part of the City of Bozeman system. According to an exploratory soil test pits on site, the soil consists of topsoil to a depth of 1.0’, followed by lean clay (brown, medium stiff, silt lenses) to a depth of 7.5’, followed by well graded gravel (multi colored, very dense to medium dense) to a depth of 17.0’. Groundwater was observed in spring and summer of 2019 and does not come within 4.4’ of the surface. The average groundwater depth at the six (6) wells was 5.69’ from the surface. The soil and groundwater found on site are suitable for this project. 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), Addendum #3. c. WQB Circular No. 1 d. City of Bozeman Zoning Map e. Uniform Plumbing Code f. City of Bozeman Water Facility Plan Update, July 2017 B. Existing Water Supply The proposed water main extension will be served from the existing City of Bozeman water distribution system in S. 11th Ave and in Arnold St. The following information regarding pressures of the existing system was obtained from the City of Bozeman: Hydrants at the intersection of Campus Blvd and S. 11th Ave. Static Pressure: 76 psi Pitot Pressure: 68 psi Residual Pressure: 72 psi Hydrant Discharge: 1,385 gpm during test, 2.5" port Distribution Main Capacity – Fire flow at minimum residual pressure Qr = Qt[(Ps – Pm)/(Ps – Pr)]0.54 Qr = 1,385 [(76 – 20)/(76 – 72)]0.54 Qr = 6,071 gpm at 20 psi Where: Qt = Hydrant Discharge During Test Pm = Minimum Residual Pressure Qr = Fire Flow at Minimum Residual Pressure Pr = Residual Pressure Ps = Static Pressure Pt = Pitot Pressure C. Proposed Water System The proposed water main extension will consist of approximately 3,920 linear feet of 8" Class 51 Ductile Iron Pipe looped throughout the subdivision and approximately 780 linear feet of 12" Class 51 Ductile Iron Pipe in Arnold St. The water main will be 12" in Arnold Street and 8" in the local streets, looped throughout the subdivision. The layout of the proposed water main will meet the City of Bozeman design criteria and will be located within the proposed right-of ways and separated from the proposed sanitary sewer main by a minimum distance of 10 feet. Fire hydrants will be installed so not to exceed 600’ spacing, fulfilling the distance requirement for fire hydrant spacing, as well as assisting in flushing of the main. Gate valves will be installed at the connection point to the existing mains as required by the City of Bozeman design standards. D. Capacity Analysis A capacity analysis was performed on the proposed water main extension. The water main extension has been designed to meet the maximum day demand plus fire flow and has also been checked for the peak hour demand. Phase IV contains R-1, R-2 and R-3 zoning. The analysis was completed based on 170 gpd per capita usage and 2.17 persons per unit. The number of dwelling units per acre is from Table V-1 of the City design standards and based on gross area. Table 1 below outlines the water demand calculations for the proposed main. TABLE 1: WATER DEMAND – RESIDENTIAL ALLISON SUBDIVISION PHASE IV Zoning Area (acres) Dwelling Units/Acre Density (residents /unit) Total Residents Daily Flow Rate/resident (gpd) Total Flow (gpd) R-1 10.67 3.9 2.17 90 170 15,300 R-2 7.21 5.2 2.17 81 170 13,770 R-3 4.88 6.5 2.17 68 170 11,560 Total Flow (gpd) 40,630 Total Flow (gpm) 28.22 Based on these parameters, Phase IV of Allison Subdivision will require an estimated water usage of 40,630 gal/day, or an average daily demand of 28.22 gpm. In addition to the average daily demand, the water main extension must account for peak periods of daily use. Peaking factors are applied to the demand and account for these peak periods in daily use. The peaking factors used are maximum daily use and peak hour and are obtained from the City of Bozeman Design Standards. Table 2 shows the peaking factors and the resultant flows from those factors when applied to the average daily demand of 28.22 gpm. TABLE 2 PEAKING FACTORS Flow Designation Peaking Factor Flow (gpm) Average Day Demand 1 28 Maximum Day Demand 2.3 64 Maximum Hour Demand 3 84 The required fire flow was estimated for allowable uses within the R-3 zone, which has a higher allowable population density than R-1 and R-2. R-3 zoning allows up to 4-household dwellings and townhouses/rowhouses with five attached units or less. Based on this criteria, it is estimated that the buildings within the R-3 lots will have a gross square footage of 10,000 sf, be non- sprinklered, and have Type V-B construction. Per the adopted 2015 International Fire Code, a 2,750 gpm flow is required for the estimated structure characteristics. A hydraulic analysis was performed using WaterCAD in order to determine operating conditions and available fire flow. A Hazen-Williams “C” Factor of 130 was used in the pipe evaluation. The working residual water pressure shall not be less than 20 psi at any point in the water distribution system under maximum day plus fire flow. The velocity shall not exceed 15 feet per second through the main line under peak hour conditions. Results The WaterCAD model shows that the available fire flows range from 3,083 gpm to 4,500 gpm under the peak hour scenario. Based on the analysis, the proposed water mains within the subdivision have adequate capacity for the maximum day demand plus fire flow and peak hour demand. No operating conditions were outside of the required conditions during the peak hour demand. A WaterCAD exhibit and reports for both the maximum demand plus fire flow and peak hour scenarios are included in the appendix. E. Conclusion Based on this analysis, the proposed 8-inch water main extensions for the development of Allison Subdivision Phase IV provide adequate service to meet the fire flow plus maximum day demand and the peak hour flows for the development. The proposed 12-inch water main extension in Arnold Street was sized to provide continuity with the Water Facility Plan Recommendation and to ensure adequate capacity for the surrounding area, once developed. This project will require the approval of the City Engineer and MDEQ. Appendix WaterCAD exhibit and reports Appendix: WaterCad Exhibit and Results Scenario: Peak Hour Flow P-57 P-58 P-38 Page 1 of 127 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 6/17/2020 WaterCAD CONNECT Edition Update 2 [10.02.00.43] Bentley Systems, Inc. Haestad Methods Solution CenterAllison WaterCad 2020-06-16.wtg Scenario: Peak Hour Flow Current Time Step: 0.000 h FlexTable: Pipe Table G:\ACAD\2018\18-118 Allison Sub\dwg\Civil\WaterCad\Allison WaterCad 2020-06-16.wtg Label Length (Scaled) (ft) Start Node Stop Node Diameter (in) Hazen- Williams C Minor Loss Coefficient (Local) Flow (gpm) Velocity (ft/s) P-1 62 R-2 PMP-1 48.0 140.0 0.000 85 0.02 P-2 54 PMP-1 J-39 48.0 140.0 0.000 85 0.02 P-3 48 H-36 J-50 6.0 130.0 2.700 0 0.00 P-4 22 H-42 J-43 6.0 130.0 2.700 0 0.00P-5 133 J-43 J-39 12.0 130.0 0.000 -85 0.24 P-6 16 H-40 J-41 6.0 130.0 2.700 0 0.00 P-7 618 J-38 J-56 8.0 130.0 0.000 11 0.07 P-8 22 H-44 J-45 6.0 130.0 2.700 0 0.00P-9 344 J-49 J-43 12.0 130.0 0.000 -85 0.24 P-10 26 J-45 J-49 12.0 130.0 0.000 -85 0.24 P-11 434 J-47 J-45 12.0 130.0 0.000 -85 0.24 P-12 168 J-31 J-47 12.0 130.0 0.000 -85 0.24P-13 139 J-41 J-32 12.0 130.0 0.000 -41 0.12 P-14 425 J-50 J-41 12.0 130.0 0.000 -41 0.12 P-15 11 J-32 J-31 12.0 130.0 0.000 -85 0.24 P-16 139 J-50 J-23 8.0 130.0 0.000 30 0.19P-17 424 J-23 J-14 8.0 130.0 0.000 6 0.04 P-18 228 J-14 J-51 8.0 130.0 0.000 6 0.04 P-19 51 J-23 J-18 8.0 130.0 0.000 25 0.16 P-20 126 J-24 J-54 8.0 130.0 0.000 16 0.10P-21 29 J-54 J-10 8.0 130.0 0.000 6 0.04 P-22 233 J-51 J-24 8.0 130.0 0.000 -11 0.07 P-23 69 J-18 J-27 8.0 130.0 0.000 8 0.05 P-24 29 J-15 J-16 8.0 130.0 0.000 -17 0.11P-25 29 J-17 J-18 8.0 130.0 0.000 -17 0.11 P-26 51 J-21 J-22 8.0 130.0 0.000 -17 0.11 P-27 101 J-10 J-22 8.0 130.0 0.000 6 0.04 P-28 209 J-27 J-16 8.0 130.0 0.000 11 0.07P-29 131 J-32 J-25 12.0 130.0 0.000 44 0.12 P-30 50 J-27 J-12 8.0 130.0 0.000 -4 0.02 P-31 206 J-12 J-6 8.0 130.0 0.000 -4 0.02 P-32 380 J-6 J-54 8.0 130.0 0.000 -4 0.02P-33 432 J-54 J-2 8.0 130.0 0.000 6 0.04 P-34 158 J-16 J-55 8.0 130.0 0.000 -6 0.04 P-35 406 J-55 J-37 8.0 130.0 0.000 -6 0.04 P-36 50 J-2 J-37 8.0 130.0 0.000 6 0.04P-37 10 H-9 J-10 6.0 130.0 0.000 0 0.00 P-38 10 H-1 J-2 6.0 130.0 2.700 0 0.00 P-39 10 H-5 J-6 6.0 130.0 2.700 0 0.00 P-40 10 H-7 J-8 6.0 130.0 2.700 0 0.00P-41 10 H-3 J-4 6.0 130.0 2.700 0 0.00 P-42 27 J-37 J-28 8.0 130.0 0.000 0 0.00 P-43 48 J-33 J-49 12.0 130.0 0.000 0 0.00 P-44 23 H-46 J-47 6.0 130.0 2.700 0 0.00P-45 19 H-13 J-14 6.0 130.0 2.700 0 0.00 P-46 127 J-35 J-32 12.0 130.0 0.000 0 0.00 P-47 10 H-11 J-12 6.0 130.0 2.700 0 0.00 P-48 59 J-49 J-34 12.0 130.0 0.000 0 0.00P-49 296 J-38 J-50 12.0 130.0 0.000 -11 0.03 P-50 51 J-19 J-20 8.0 130.0 0.000 0 0.00 P-51 122 J-20 J-56 8.0 130.0 0.000 -11 0.07 P-52 30 J-56 J-30 8.0 130.0 0.000 0 0.00P-53 146 J-8 J-20 8.0 130.0 0.000 -11 0.07 P-54 160 J-29 J-53 8.0 130.0 0.000 0 0.00 P-55 219 J-53 J-24 8.0 130.0 0.000 27 0.17 P-56 425 J-25 J-4 12.0 130.0 0.000 27 0.08P-57 33 J-4 J-53 12.0 130.0 0.000 27 0.08 P-58 330 J-53 J-26 12.0 130.0 0.000 0 0.00 P-59 177 J-22 J-8 8.0 130.0 0.000 -11 0.07 Page 1 of 1 6/17/2020file:///C:/Users/Tech7/AppData/Local/Temp/Bentley/WaterCAD/xw0dptut.xml Scenario: Peak Hour Flow Current Time Step: 0.000 h FlexTable: Junction Table G:\ACAD\2018\18-118 Allison Sub\dwg\Civil\WaterCad\Allison WaterCad 2020-06-16.wtg Label Elevation (ft) Demand (gpm) Hydraulic Grade (ft) Pressure (psi) Pressure (Minimum) (psi) H-1 4,964.00 0 5,137.44 75 75 H-3 4,963.00 0 5,137.45 75 75 H-5 4,963.00 0 5,137.44 75 75 H-7 4,955.00 0 5,137.44 79 79 H-9 4,963.00 0 5,137.44 75 75 H-11 4,962.00 0 5,137.44 76 76 H-13 4,966.00 0 5,137.44 74 74 H-36 4,963.00 0 5,137.44 75 75 H-40 4,963.00 0 5,137.45 75 75 H-42 4,983.00 0 5,137.47 67 67 H-44 4,978.00 0 5,137.46 69 69 H-46 4,972.00 0 5,137.45 72 72 J-2 4,956.00 0 5,137.44 79 79 J-4 4,955.00 0 5,137.45 79 79J-6 4,955.00 0 5,137.44 79 79 J-8 4,947.00 0 5,137.44 82 82 J-10 4,950.00 0 5,137.44 81 81J-12 4,953.00 0 5,137.44 80 80 J-14 4,958.00 0 5,137.44 78 78 J-15 4,956.00 17 5,137.44 78 78J-16 4,950.00 0 5,137.44 81 81 J-17 4,954.00 17 5,137.44 79 79 J-18 4,954.00 0 5,137.44 79 79J-19 4,945.00 0 5,137.44 83 83 J-20 4,945.00 0 5,137.44 83 83 J-21 4,955.00 17 5,137.44 79 79 J-22 4,958.00 0 5,137.44 78 78 J-23 4,955.00 0 5,137.44 79 79 J-24 4,953.00 0 5,137.44 80 80 J-25 4,957.00 17 5,137.45 78 78 J-26 4,949.00 0 5,137.45 82 82 J-27 4,953.00 0 5,137.44 80 80 J-28 4,944.00 0 5,137.44 84 84 J-29 4,957.00 0 5,137.45 78 78 J-30 4,944.00 0 5,137.44 84 84 J-31 4,957.00 0 5,137.45 78 78 J-32 4,957.00 0 5,137.45 78 78J-33 4,968.00 0 5,137.46 73 73 J-34 4,968.00 0 5,137.46 73 73 J-35 4,956.00 0 5,137.45 79 79J-37 4,944.00 0 5,137.44 84 84 J-38 4,948.00 0 5,137.44 82 82 J-39 4,975.00 0 5,137.48 70 70J-41 4,955.00 0 5,137.45 79 79 J-43 4,973.00 0 5,137.47 71 71 J-45 4,968.00 0 5,137.46 73 73J-47 4,958.00 0 5,137.45 78 78 J-49 4,968.00 0 5,137.46 73 73 J-50 4,955.00 0 5,137.44 79 79 J-51 4,955.00 17 5,137.44 79 79 J-53 4,955.31 0 5,137.45 79 79 J-54 4,950.54 0 5,137.44 81 81 J-55 4,948.32 0 5,137.44 82 82 J-56 4,944.20 0 5,137.44 84 84 Page 1 of 1 6/17/2020file:///C:/Users/Tech7/AppData/Local/Temp/Bentley/WaterCAD/h4w0ukmn.xml Scenario: Peak Hour Flow Current Time Step: 0.000 h FlexTable: Reservoir Table G:\ACAD\2018\18-118 Allison Sub\dwg\Civil\WaterCad\Allison WaterCad 2020-06-16.wtg ID Label Elevation (ft)Flow (Out net) (gpm) Hydraulic Grade (ft) 114 R-2 4,995.00 85 4,995.00 Page 1 of 1 6/17/2020file:///C:/Users/Tech7/AppData/Local/Temp/Bentley/WaterCAD/rexzw3ew.xml Scenario: Peak Hour Flow Current Time Step: 0.000 h FlexTable: Pump Table G:\ACAD\2018\18-118 Allison Sub\dwg\Civil\WaterCad\Allison WaterCad 2020-06-16.wtg ID Label Elevation (ft) Pump Definition Status (Initial) Hydraulic Grade (Suction) (ft) Hydraulic Grade (Discharge) (ft) Flow (Total) (gpm) Pump Head (ft) 115 PMP-1 4,990.00 Pump Definition - 1 On 4,995.00 5,137.48 85 142.48 Page 1 of 1 6/17/2020file:///C:/Users/Tech7/AppData/Local/Temp/Bentley/WaterCAD/yeftyqy2.xml Scenario: Automated Fire Flow Analysis Current Time Step: 0.000 h Fire Flow Node FlexTable: Fire Flow Report G:\ACAD\2018\18-118 Allison Sub\dwg\Civil\WaterCad\Allison WaterCad 2020-06-16.wtg Label Fire Flow (Needed) (gpm) Fire Flow (Available) (gpm) Flow (Total Needed) (gpm) Flow (Total Available) (gpm) Pressure (Calculated Residual) (psi) Pressure (Zone Lower Limit) (psi) Pressure (Calculated Zone Lower Limit) (psi) Junction w/ Minimum Pressure (Zone) Velocity of Maximum Pipe (ft/s) Pipe w/ Maximum Velocity H-1 2,750 3,083 2,750 3,083 20 20 48 J-2 11.55 P-33 H-3 2,750 3,566 2,750 3,566 20 20 54 H-13 10.36 P-15H-5 2,750 3,248 2,750 3,248 20 20 51 J-6 11.13 P-30H-7 2,750 3,300 2,750 3,300 20 20 52 J-8 13.02 P-21 H-9 2,750 4,500 2,750 4,500 29 20 37 J-22 22.25 P-21 H-11 2,750 3,349 2,750 3,349 20 20 50 H-5 14.97 P-30H-13 2,750 3,101 2,750 3,101 20 20 51 J-14 10.12 P-17H-36 2,750 3,187 2,750 3,187 20 20 56 H-13 9.28 P-5 H-40 2,750 3,577 2,750 3,577 20 20 54 H-13 10.39 P-9 H-42 2,750 3,673 2,750 3,673 20 20 62 H-44 10.66 P-5H-44 2,750 3,575 2,750 3,575 20 20 60 H-42 10.38 P-5H-46 2,750 3,480 2,750 3,480 20 20 58 H-44 10.11 P-5 J-2 2,750 4,327 2,750 4,327 23 20 20 H-1 16.21 P-33 J-4 2,750 4,500 2,750 4,500 46 20 42 H-3 13.01 P-11J-6 2,750 4,500 2,750 4,500 29 20 26 H-5 15.42 P-30J-8 2,750 4,500 2,750 4,500 30 20 26 H-7 17.72 P-21 J-10 2,750 4,500 2,750 4,500 39 20 34 H-9 22.25 P-21 J-12 2,750 4,500 2,750 4,500 35 20 31 H-11 20.12 P-30J-14 2,750 4,500 2,750 4,500 26 20 23 H-13 14.68 P-17J-15 2,750 4,500 2,767 4,517 21 20 28 J-16 28.83 P-24 J-16 2,750 4,500 2,750 4,500 28 20 25 J-15 19.61 P-28 J-17 2,750 4,500 2,767 4,517 35 20 37 H-11 28.83 P-25J-18 2,750 4,500 2,750 4,500 39 20 37 H-11 19.15 P-19J-19 2,750 4,500 2,750 4,500 22 20 28 J-20 28.72 P-50 J-20 2,750 4,500 2,750 4,500 28 20 28 J-19 15.93 P-21J-21 2,750 4,500 2,767 4,517 25 20 31 J-22 28.83 P-26J-22 2,750 4,500 2,750 4,500 31 20 32 J-21 20.29 P-21J-23 2,750 4,500 2,750 4,500 41 20 38 H-13 16.02 P-16 J-24 2,750 4,500 2,750 4,500 42 20 38 H-13 14.06 P-55J-25 2,750 4,500 2,767 4,517 48 20 46 H-13 13.01 P-11J-26 2,750 4,500 2,750 4,500 42 20 42 H-3 13.01 P-9 J-27 2,750 4,500 2,750 4,500 38 20 34 H-11 16.93 P-19 J-28 2,750 4,389 2,750 4,389 23 20 20 H-1 28.01 P-42J-29 2,750 4,500 2,750 4,500 24 20 42 H-3 28.72 P-54J-30 2,750 4,500 2,750 4,500 24 20 28 J-56 14.52 P-21 J-31 2,750 4,500 2,750 4,500 50 20 47 H-13 13.01 P-5 J-32 2,750 4,500 2,750 4,500 50 20 46 H-13 13.01 P-5J-33 2,750 4,500 2,750 4,500 56 20 53 H-44 13.01 P-5J-34 2,750 4,500 2,750 4,500 56 20 53 H-44 13.01 P-5 J-35 2,750 4,500 2,750 4,500 48 20 46 H-13 13.01 P-5 J-37 2,750 4,389 2,750 4,389 27 20 20 H-1 15.81 P-33J-38 2,750 4,500 2,750 4,500 45 20 42 H-13 13.01 P-5J-39 2,750 4,500 2,750 4,500 63 20 60 H-42 0.81 P-2 J-41 2,750 4,500 2,750 4,500 49 20 45 H-13 13.01 P-9 J-43 2,750 4,500 2,750 4,500 61 20 57 H-42 13.01 P-5J-45 2,750 4,500 2,750 4,500 57 20 52 H-44 13.01 P-9J-47 2,750 4,500 2,750 4,500 53 20 47 H-46 13.01 P-5 J-49 2,750 4,500 2,750 4,500 57 20 53 H-44 13.01 P-5 J-50 2,750 4,500 2,750 4,500 45 20 42 H-36 13.01 P-5J-51 2,750 4,500 2,767 4,517 30 20 30 H-13 18.06 P-22J-53 2,750 4,500 2,750 4,500 45 20 42 H-3 13.01 P-15 J-54 2,750 4,500 2,750 4,500 41 20 36 H-9 14.14 P-20 J-55 2,750 4,500 2,750 4,500 24 20 27 H-1 17.46 P-28J-56 2,750 4,500 2,750 4,500 28 20 28 J-30 14.52 P-21 Page 1 of 1 6/17/2020file:///C:/Users/Tech7/AppData/Local/Temp/Bentley/WaterCAD/jgnjycyp.xml