HomeMy WebLinkAbout020 - EXHIBIT O - WATER & SEWER DEMANDSMEMORANDUM PAGE 1 OF 2 SEPTEMBER 2025 MEMORANDUM To: City of Bozeman Engineering Department From: Bobby Egeberg, PE Date: 9/5/2025 Reference: Water and Sewer Demand Calculations - Idaho Pole Annexation I have evaluated the projected water, and sewer demands for the Idaho Pole Annexation project, a 17.92-acre property located in Gallatin County, MT near the City limits of Bozeman, see Appendix A. 17.92-acres is the gross area of the annexation for the property, the developable property will have a smaller area. The City of Bozeman Design and Construction Standards (October 2024) were utilized in evaluating the projected water and sewer demands for the project. WATER DEMAND Existing water demands for the site are zero as it is an undeveloped property. Proposed water demands were determined per Section 4.2.5 & 4.2.6 of the standards. Since detailed development plans are not finalized, demand calculations were completed using the R-3 Zoning within Table 4.2.2 and 4.2.3: Average Day Demand (2,380 gpad): 17.92 acres x 2,380 gpad = 42,650 gpd Maximum Day Demand (MDD): 2.3 x 42,650 gpd = 98,095 gpd Peak Hour Demand (PHD): 3.0 x 42,650 gpd = 127,950 gpd
MEMORANDUM PAGE 2 OF 2 SEPTEMBER 2025 Fire flow demand was determined per Section 4.2.7 and Table 4.2.4 of the standards. Single Family Low and Medium Density 1,500 gpm SEWER DEMAND Existing sewer demands for the site are zero as it is an undeveloped property. Proposed sewer demands were determined per Section 5.2.4 of the standards. Since detailed development plans are not finalized, demand calculations were completed using the R-3 Zoning within Table 5.2.1: Domestic Flow (2,100 gpad): 17.92 acres x 2,100 gpad = 37,632 gpd Domestic Flow + Base Infiltration (2,250 gpad): 17.92 acres x 2,250 gpad = 40,320 gpd A peaking factor of 4.2 was determined from the peaking factor formula in section 5.2.5. Peak Domestic Flow + Base Infiltration (gpd): 4.2 x 40,320 gpd = 169,344 gpd APPENDIX Appendix A – EXHIBIT G ANNEXATION MAP