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Home My WebLink About015_Water&SewerReport BOZEMAN HEALTH EMERGENCY DEPARTMENT EXPANSION AND RENOVATION ENABLING Project # 17095.16 Bozeman, Montana JUNE 2026 MEMORANDUM PAGE 1 OF 4 JUNE 2026 MEMORANDUM To: City of Bozeman Engineering Department From: Bobby Egeberg, PE Date: 06/19/2026 Reference: Water and Sewer Demand Calculations – Bozeman Health ED Expansion We have evaluated the projected water and sewer demands for the Bozeman Health Emergency Department Expansion project in Bozeman, Montana. The legal description for the project property is defined as: S17, T02 S, R06 E, C.O.S. 2047, PARCEL 2, ACRES 34.428, PLUS VACATED STREET AND LESS PLAT J-483. The following report summarizes the water and sewer main capacity calculations for the water and sewer services to the proposed Bozeman Health Emergency Department. The City of Bozeman Design and Construction Standards (October 2024) and the Circular DEQ-4 (December 2023) were utilized in evaluating the projected water and sewer demands for the project. WATER DEMAND The existing water system consists of a 10-inch water main, water services, valves, and a hydrant as shown on the Overall Site Plan in Appendix A that is tied into a 12-inch main that runs along Highland Boulevard. A portion of the 10-inch main will be rerouted and the existing water service will be extended within the building to provide water to the expanded emergency department. The existing fire sprinkler service will be removed and reinstalled in a new location as part of the building expansion. Typical flow values per unit from Table 3.1-1 of Circular DEQ-4 were used for demand calculations. Average Day Demand (ADD): 25 employees x 10 gpd + 24 beds x 165 gpd = 4,210 gpd = 2.92 gpm Maximum Day Demand (MDD): 2.3 x 4,210 gpd = 9,683 gpd = 6.72 gpm MEMORANDUM PAGE 2 OF 4 JUNE 2026 Peak Hour Demand (PHD): 3.0 x 4,210 gpd = 12,630 gpd = 8.77 gpm The additional water demands from the expansion of the emergency department are within the capacity of the existing water service and meter. Hydrant pressures were provided by City of Bozeman and fire flow curves for the 13 hydrants are provided in Appendix B. Hydrant #2503 has capacity to provide 7,200 gpm with a residual pressure of 20.64 psi and hydrant #3274 has capacity to provide 5,800 gpm with a residual pressure of 19.9 psi. The minimum flowrate requirement for a Type V-B building with the greatest fire flow area in Table B105.1 and Table B105.2 of the 2021 International Fire Code is 2,000 gpm measured at 20-psi residual pressure. The two hydrants nearest the emergency department expansion are well above this standard. SEWER DEMAND The existing sewer service that provides service to the existing emergency department project site is a 6-inch line that ties into the 12-inch sewer main running along the east side of Highland Boulevard. Capacity calculations were conducted and can be found in Appendix C. The capacity of the proposed 6-inch sewer main at the existing slope of 0.016 ft/ft is 415 gpm. Assuming the pipe does not exceed 75 percent of full flow capacity, the available capacity is 311 gpm. The available pipe capacity exceeds the calculated peak hour demand, so the proposed sewer main is appropriately sized to convey the anticipated sewer demands. Proposed sewer demands were determined per Section 5.2.4 of the City Standards. Typical flow values per unit from Table 3.1-1 of Circular DEQ-4 were used for demand calculations. Average Daily Flow: 25 additional employees x 10 gpd + 24 beds x 165 gpd = 4,210 gpd = 2.92 gpm 20 existing employees x 10 gpd + 20 existing beds x 165 gpd = 3,500 gpd = 2.43 gpm Total ADF = 7,710 gpd = 5.35 gpm Base Infiltration Rate: 630 gallons/acre/day x 1.3 acres = 819 gpd = 0.57 gpm MEMORANDUM PAGE 3 OF 4 JUNE 2026 Average Daily Flow + Base Infiltration Rate: 7,710 gpd + 819 gpd = 8,529 gpd = 5.92 gpm A peaking factor of 4.22 was determined from the peaking factor formula in section 5.2.5. Peak Flow: 4.22 x 8,529 gpd = 36,004 gpd = 25.0 gpm MEMORANDUM PAGE 4 OF 4 JUNE 2026 APPENDICES APPENDIX A – SITE MAP APPENDIX B – FIRE FLOW DATA APPENDIX C – CAPACITY CALCULATIONS BOZEMAN HEALTH EMERGENCY DEPARTMENT EXPANSION AND RENOVATION ENABLING Project # 17095.16 APPENDIX A SITE MAP BOZEMAN HEALTH EMERGENCY DEPARTMENT EXPANSION AND RENOVATION ENABLING Project # 17095.16 APPENDIX B FIRE FLOW DATA CITY OF BOZEMAN Fire Flow Request Form PHONE (406) 582-3200 FAX (406) 582-3201 Date May 12, 2023 Location Bozeman Deaconess Hospital Pressure Zone South (HGL 5125) GIS Hydrant ID# 2796, 2818, 2819, 2820, 764, 1040, 569, 1335, 2510, 1930, 3274, 2503, 790 Adjacent Main Size 10-inch DI, 10-inch DI, 10-inch DI, 10-inch DI, 8-inch DI, 10-inch DI, 10-inch DI, 10-inch DI, 10-inch DI, 8-inch DI, 10-inch DI, 10-inch DI Model Scenario Maximum Day Demand, Steady State, Fire Flow Reference 2017 Water Facility Plan Update1 Hydrant Curves An Excel Spreadsheet with hydrant curves has been provided for the requested location Requested Location via the Bozeman Infrastructure Viewer2 If you have questions or need further information feel free to email. Data Disclaimer: Water distribution information is calculated using hydraulic modeling software and is subject to variation. Actual field conditions may vary. This information is provided to the requestor for evaluation purposes only, without warranty of any kind, including, but not limited to any expressed or implied warranty arising by contract, stature, or law. In no event regardless of cause, shall the City be liable for any direct, indirect, special, punitive or consequential damages of any kind whether such damages arise under contract, tort, strict liability or inequity. HOME OF MONTANA STATE UNIVERSITY GATEWAY TO YELLOWSTONE PARK 1 https://www.bozeman.net/home/showpublisheddocument/4977/636420174896170000 2 https://gisweb.bozeman.net/Html5Viewer/?viewer=infrastructure GIS Hydrant # Available Flow (gpm) Residual Pressure (psi)2503 0 76.54 200 76.3 400 75.97 600 75.57 800 75.11 1,000.00 74.55 1,200.00 73.93 1,400.00 73.22 1,600.00 72.43 1,800.00 71.56 2,000.00 70.61 2,200.00 69.58 2,400.00 68.48 2,600.00 67.29 2,800.00 66.03 3,000.00 64.7 3,200.00 63.29 3,400.00 61.81 3,600.00 60.26 3,800.00 58.64 4,000.00 56.94 4,200.00 55.18 4,400.00 53.34 4,600.00 51.44 4,800.00 49.47 5,000.00 47.43 5,200.00 45.33 5,400.00 43.15 5,600.00 40.91 5,800.00 38.61 6,000.00 36.23 6,200.00 33.8 6,400.00 31.29 6,600.00 28.73 6,800.00 26.09 7,000.00 23.4 7,200.00 20.64 7,400.00 17.81 7,600.00 14.93 7,800.00 11.98 8,000.00 8.96 8,200.00 5.89 8,400.00 2.75 8,571.93 0 Hydrant Curve 0 10 20 30 40 50 60 70 80 90 0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000Residual Pressure (psi)Available Flow (gpm) Hydrant Curve 2503 Data Disclaimer: Water distribution information is calculated using hydraulic modeling software and is subject to variation. Actual field conditions may vary. This information is provided to the requestor for evaluation purposes only, without warranty of any kind, including, but not limited to any expressed or implied warranty arising by contract, stature, or law. In no event regardless of cause, shall the City be liable for any direct, indirect, special, punitive or consequential damages of any kind whether such damages arise under contract, tort, strict liability or inequity. GIS Hydrant # Available Flow (gpm) Residual Pressure (psi)3274 0 81.83 200 81.52 400 81.04 600 80.42 800 79.69 1,000.00 78.84 1,200.00 77.85 1,400.00 76.71 1,600.00 75.43 1,800.00 74.02 2,000.00 72.48 2,200.00 70.8 2,400.00 69 2,600.00 67.06 2,800.00 65.01 3,000.00 62.82 3,200.00 60.52 3,400.00 58.09 3,600.00 55.55 3,800.00 52.88 4,000.00 50.1 4,200.00 47.2 4,400.00 44.18 4,600.00 41.05 4,800.00 37.81 5,000.00 34.45 5,200.00 30.98 5,400.00 27.4 5,600.00 23.7 5,800.00 19.9 6,000.00 15.98 6,200.00 11.95 6,400.00 7.82 6,600.00 3.57 6,764.65 0 Hydrant Curve 0 10 20 30 40 50 60 70 80 90 0 1000 2000 3000 4000 5000 6000 7000 8000Residual Pressure (psi)Available Flow (gpm) Hydrant Curve 3274 Data Disclaimer: Water distribution information is calculated using hydraulic modeling software and is subject to variation. Actual field conditions may vary. This information is provided to the requestor for evaluation purposes only, without warranty of any kind, including, but not limited to any expressed or implied warranty arising by contract, stature, or law. In no event regardless of cause, shall the City be liable for any direct, indirect, special, punitive or consequential damages of any kind whether such damages arise under contract, tort, strict liability or inequity. BOZEMAN HEALTH EMERGENCY DEPARTMENT EXPANSION AND RENOVATION ENABLING Project # 17095.13 APPENDIX C CAPACITY CALCULATIONS Project: 17095.16 Bozeman Health ED Date: 06/19/2026 6-INCH Capacity Calclulations .016 FT/FT Slope 6" Pipe Flowing Full Capacity 0.93 cfs 6" Pipe Flowing Full Capacity 415 gal/min Q/Qfull @ 75% full 0.75 per nomograph Capacity @ 75% full 311 gal/min Total Peak Hourly Flow plus Infiltration 25.00 gal/min Result Q/Qfull based on peak hour 0.08 Percent Full for 6" From Nomograph at peak hour 24%