The URL can be used to link to this page

Home My WebLink About04 1825 W Kagy_Engineering Design Report Water & Sewer JOB NO. B26-010 MONTANA | WASHINGTON | IDAHO | NORTH DAKOTA | PENNSYLVANIA REV. JULY 2026 406.586.0277 tdhengineering.com 234 East Babcock Street Suite 3 Bozeman, MT 59715 CLIENT ENGINEER Reuter Walton Development 4450 Excelsior Boulevard, Suite 400 St. Louis Park, MN 55416 TD&H Engineering 234 East Babcock Street, Suite 3 Bozeman, MT 59715 Engineer: Cody Croskey, PE 1825 W KAGY AFFORDABLE HOUSING BOZEMAN, MONTANA BASIS OF DESIGN REPORT – SEWER & WATER Image courtesy of Kaas Wilson Architects 7/24/2026 B26-010 1825 W Kagy Affordable Housing Page 1 of 2 1825 W KAGY AFFORDABLE HOUSING ENGINEERING DESIGN REPORT – SEWER & WATER Rev. JULY 2026 Purpose and Introduction The purpose of this report is to explain how water and sanitary sewer improvements will be designed to meet the City of Bozeman requirements and Montana Public Works Standard Specifications (MPWSS) to provide service to a new multi-family affordable housing building near Montana State University in Bozeman, Montana. The project is located at the NE corner of S. 19th Avenue and West Kagy Boulevard. The parcel is comprised of Lot 7 and Tract B of the Remington Addition to the City of Bozeman totaling 3.36 acres in size. The property is currently developed with a church building, parking lot, and landscaped open space. Proposed site improvements include the demolition of the existing building and construction of a new multi-story residential building. The new building will run along the west and south sides of the lot with parking to the north. On-site infrastructure improvements will include the relocation of a fire hydrant and the addition of another fire hydrant. No off-site infrastructure improvements are currently anticipated. Design Report Water The property has a live water service connected to the existing church building and an irrigation well. The domestic service will be abandoned at its connection point with the water main in conjunction with demolition activities at the site. The existing well on the east side of the property will be properly abandoned. A new 6-inch (est.) domestic water service and 6-inch (est.) fire service line will be extended to the new building from the existing 8-inch water main that crosses the northwest portion of the site. Final water service sizing will be verified by the mechanical and fire suppression engineers in accordance with the Uniform Plumbing Code, actual fixture unit counts, and NFPA. The services will be Class 51 ductile iron and be installed per the City of Bozeman Design Standards and Modifications to Montana Public Works Standard Specifications (MPWSS). The proposed water and fire services are approximately 250’-260’ in length, exceeding the 150’ maximum identified in the City’s Design and Construction Standards. A waiver request to allow longer service lengths for this project is being submitted to the City Engineering Department with supporting calculations. The estimated domestic water and fire flow demands for the project are summarized in Table 1 below. Supporting assumptions and calculations in accordance with C.O.B. Design and Construction Standards Section 4.2 are provided in Appendix A. B26-010 1825 W Kagy Affordable Housing Page 2 of 2 Table 1: Estimated New Water Demands Average Day Max. Day Peak Hour New Building Demand 47,458 gpd 75.8 gpm 98.9 gpm The fire flow requirement for the new building is 1,938 gpm based on building size and construction type as determined following International Fire Code Appendix B criteria. Fire hydrant flow reports were provided by the City Engineering Department for the nearest existing fire hydrants to confirm available fire flows. The hydrant flow data for Hydrant #1051 adjacent to the new building service connections indicates an available fire flow of 8,000 gpm in the water main before dropping below a residual pressure of 20 psi. The project fire flow determination and fire hydrant flow reports are provided in appendix A. Sewer The property has a live sewer service connected to the existing church building. The domestic service will be abandoned at its connection point with the sewer main in conjunction with demolition activities at the site. Two new 8” (est.) sewer services are proposed to extend from the new building to the existing sewer manhole on the north side of the site that runs north down Lloyd Street to the 15” interceptor sewer at Lincoln Street. Final service sizing will be verified by the mechanical engineer in accordance with the Uniform Plumbing Code and actual fixture unit counts. The new 8” sewer service lines will be SDR-26 PVC and will be installed per the City of Bozeman Design Standards and Modifications to Montana Public Works Standard Specifications (MPWSS). This will require connections to existing manhole #H0701 at the uphill end of the existing Lloyd Street sewer main. The estimated sewer demands for the project are summarized in Table 2 below. Supporting assumptions and calculations in accordance with C.O.B. Design and Construction Standards Section 5.2 are provided in Appendix B. Table 2: Estimated New Sewer Demands Average Day (gpd) Peak Hour (gpm) New Building Demand 22,639 - Lot Infiltration 504 - Total Sewer Demand 23,143 63.99 APPENDIX A Water Calculations 1825 W Kagy Affordable Housing Date: Rev. 7.24.2026 Water Demand Calculations Domestic Water Demand: Residential Use: Residential Units =162 units Population =351.5 people (2.17 people/unit per COB Design Standards) Residential Flow =47,458 GPD (135 gpcd per COB Design Standards) Peak Hour Demand: Average Day Demand =47,458 GPD (All Uses) Average Day Demand =33.0 gpm (GPD / 1,440 minutes) Maximum Day Demand =75.8 gpm (Ave. Day x Peaking Factor = 2.3) Peak Hour Demand =98.9 gpm (Ave. Day x Peaking Factor = 3) Fire Flow Requirement: IBC Construction Type =VA Fire Flow Calculation Area =181,763 GSF Fire Flow Requirement =7,750 GPM (per IFC Table B105.1(2) for total building area) Automatic Fire Sprinkler System =Yes Fire Sprinkler System Type =NFPA 13 Reduced Fire Flow Requirement =1,938 gpm (25% of Total or 1,000 GPM min. per IFC Table B105.2) CITY OF BOZEMAN Fire Flow Request Form PHONE (406) 582-3200 FAX (406) 582-3201 Date October 11, 2022 Location S 19th Ave and W. Kagy Blvd Pressure Zone SOUTH (HGL 5125 ) GIS Hydrant ID# 495, 1051, and 1110 Adjacent Main Size 6-inch DI, 8-inch DI, and 12-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 Connect new domestic & fire lines here Hydrant # 1051: 8,000 gpm @ 21 psi 24" 8"6" GIS Hydrant #Available Flow (gpm)Residual Pressure (psi)1051083.2720082.9640082.5760082.180081.551,000.00 80.931,200.00 80.231,400.00 79.471,600.00 78.651,800.00 77.762,000.00 76.812,200.00 75.82,400.00 74.722,600.00 73.592,800.00 72.413,000.00 71.163,200.00 69.863,400.00 68.5 3,600.00 67.09 3,800.00 65.61 4,000.00 64.07 4,200.00 62.47 4,400.00 60.81 4,600.00 59.1 4,800.00 57.32 5,000.00 55.49 5,200.00 53.61 5,400.00 51.67 5,600.00 49.67 5,800.00 47.61 6,000.00 45.5 6,200.00 43.33 6,400.00 41.1 6,600.00 38.82 6,800.00 36.48 7,000.00 34.09 7,200.00 31.65 7,400.00 29.15 7,600.00 26.6 7,800.00 23.99 8,000.00 21.33 8,200.00 18.61 8,400.00 15.84 8,600.00 13.02 8,800.00 10.14 9,000.00 7.2 9,200.00 4.21 9,400.00 1.15 9,474.14 0.01 Hydrant Curve 0 10 20 30 405060708090 0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000Residual Pressure (psi)Available Flow (gpm) Hydrant Curve 1051 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. APPENDIX B Sewer Calculations 1825 W Kagy Affordable Housing Date: Rev. 7.24.2026 Sewer Demand Calculations Average Day Sewer Demand : Residential Use: Residential Units =162 units Population =351.5 people (2.17 people/unit per COB Design Standards) Residential Flow =22,639 GPD (64.4 gpcd per COB Design Standards) Infiltration: Property Size =3.36 acres Infiltration Flow =504 GPD (150 gpd/acre per COB Design Standards) Total Development Average Day Demand: 23,143 GPD (residential + infiltration) Total Development Peak Sewer Flow: Average Day Demand =22,639 GPD (total domestic flow) P =0.352 (population/1,000) Peaking Factor =4.05 Peak Sewer Demand =91,647 GPD (avg. day demand)*(peaking factor) + Infiltration Flow =504 GPD (not peaked) Total Peak Flow =92,151 GPD (residential + commercial + infiltration) Peak Sewer Flow =63.99 GPM (peak flow)/(24 hrs/day)/(60 min/hr) 𝑄𝑚𝑎𝑥 𝑄𝑎𝑣𝑔 =18 +𝑠ℎ𝑛𝑠𝑠𝑎𝑛𝑑𝑠𝑛𝑑𝑛𝑑𝑛𝑛𝑙𝑑1/2 4 +𝑠ℎ𝑛𝑠𝑠𝑎𝑛𝑑𝑠𝑛𝑑𝑛𝑑𝑛𝑛𝑙𝑑1/2