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Home My WebLink About07 1825 Kagy_Water Service Length Waiver Request BOZEMAN, GREAT FALLS, KALISPELL & SHELBY, MT | SPOKANE, WA | LEWISTON, ID | WATFORD CITY, ND | MEDIA, PA 406.586.0277 tdhengineering.com 234 East Babcock Street Suite 3 Bozeman, MT 59715 MEMORANDUM Date: May 4, 2026 TDH Job No.: B26-010 To: City of Bozeman Engineering Department From: Cody Croskey, PE Subject: 1825 W. Kagy Affordable Housing Water Service Length Waiver Request The purpose of this memo is to request an administrative waiver from the City of Bozeman’s Design and Construction Standards Section 4.2.9.C: I. The length of service lines from the main to the structure may not exceed 150 feet in length, unless approved in writing by the city. This request is being made in accordance with Section 1.9 of the Design and Construction Standards, and addresses the evaluation criteria of Section 1.9.2 and the applicable design criteria of Section 4.2 for consideration. The current plan for the 1825 W Kagy Affordable Housing project has a 160-unit building being constructed tight to the S. 19th Ave and W. Kagy Blvd setbacks to meet the double primary frontage and build-to requirements of the newly adopted UDC. This results in a long L-shaped building with units facing the primary street frontages and mechanical/service rooms located at the core, interior to the site. The closest available water distribution main of appropriate size to serve this building is located at the NW end of the site, approximately 250’-260’ away from the new central water entry room. As opposed to extending a dead-end public main further into the site to serve only this building, a waiver is requested to allow two parallel and privately maintained water and fire service lines to extend directly from the existing looped water main to serve the new building. 1.9.2 Administrative Waiver Review Criteria: A. The deviation from standards is not in conflict with applicable state and federal codes and requirements. Justification: The longer service lengths are not in conflict with applicable state or federal requirements or codes. The service lines will be sized to deliver adequate flow and pressure to the building as determined by the City’s Design and Construction Standards and currently adopted plumbing and fire codes. tdhengineering.com PAGE NO. 2 MAY 4, 2026 B. The deviation from standards will not harm, or will be beneficial to, the public in general. Justification: Installing adequately sized parallel services in-lieu of a dead-end water main extension on this site is not expected to have any harmful effects on the public. C. The deviation from standards is consistent with the general purpose of standards to protect public health and safety and promote operational efficiency while minimizing life-cycle costs of public infrastructure. Justification: The water service lines will be constructed with the same materials and installation standards as public water mains, and will be sized to meet the design criteria in Section 4.2 of the City’s design standards for pressure and flow. The service lines will also be privately maintained which would keep the amount of public infrastructure and associated maintenance costs to a minimum on this site. 4.2.2 Water System Design Criteria: Project Water Demands (see project Engineering Design Report): Average Daily Demand (ADD) 46,872 GPD Maximum Day demand (MDD) 74.9 GPM Peak Hour demand (PHD) 97.7 GPM Fire Flow Demand 1,938 GPM A fire hydrant flow report for the nearest adjacent fire hydrant (#1051) was provided by the City Engineering Department and used to model the proposed water service lines. Based on the provided flow report, the static pressure in the water main where the new services will connect is 83.27 psi and 8,000 gpm is available before dropping below 20 psi residual pressure in the system (fire flow report attached). The maximum day plus fire flow demand for this building is calculated as 1,983 gpm + 74.9 gpm = 2,013 gpm. As demonstrated by the attached modeling results for the proposed water service pipes, the static pressure will be 79.9 psi at the building and 2,988 gpm will be available before dropping below 20 psi residual pressure. The maximum velocity in the service pipe will also be below 5 fps under Peak Hour (PHD) conditions. Therefore, the proposed water and fire services are expected to adequately supply the building demands while meeting the same design criteria as a dead- end water main if it were to be extended for the sole purpose of reducing the service lengths. tdhengineering.com PAGE NO. 3 MAY 4, 2026 Thank you for considering a waiver to the maximum service line length standard for this project. Please let me know if you have any questions or require any additional information. Sincerely, Cody Croskey PE Civil Engineer TD&H ENGINEERING I:\2026\BOZ\B26-010 Kagy LIHTC \05_DESIGN\CIVIL\DESIGN REPORTS\Water SERVICE LENGTH WAIVER\1825 KAGY WATER SERVICE LENGTH WAIVER REQUEST.DOC 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. Scenario: Base P-1 8"P-2 8"P-3 8" P-R-1 HYDRANT - (02) WTR MAIN NORTH WTR SVC CONNECTFIRE SVC CONNECT WTR SVC FIRE SVC TEE - (02) 8-IN EX. HYDRANT #1051 HYDRANT - (01) R-1 B26-010 Kagy LIHTC Water Model.wtg WaterCAD [24.00.03.22] 5/5/2026 Page 1 of 1 Fire Flow Node FlexTable: Fire Flow Results Table Label Flow (Total Available) (gpm) Junction w/ Minimum Pressure (System) Fire Flow (Upper Limit) (gpm) Fire Flow (Needed) (gpm) Pressure (Calculated Residual)(psi) Pressure (Calculated System Lower Limit) (psi) Notes FIRE SVC CONNECT 2,988 HYDRANT - (02)3,500 1,938 20 80 6-IN WTR SVC CONNECT 2,995 HYDRANT - (02)3,500 1,938 20 81 6-IN B26-010 Kagy LIHTC Water Model.wtg WaterCAD [24.00.03.22] 5/5/2026 Page 1 of 1 Available fire flow at end of ~250' 6" service line Residual FlexTable: Pipe Table Label Start Node Stop Node Diameter (in) Material Hazen-Williams C Length (User Defined) (ft) Flow (gpm) Velocity (ft/s) P-4 8"TEE - (02) 8-IN EX. HYDRANT #1051 8.0 Ductile Iron 130.0 13 -98 0.62 P-5 8"EX. HYDRANT #1051 HYDRANT - (01)8.0 Ductile Iron 130.0 27 0 0.00 P-6 8"HYDRANT - (01)WTR MAIN NORTH 8.0 Ductile Iron 130.0 74 0 0.00 P-1 8"HYDRANT - (02)FIRE SVC 8.0 Ductile Iron 130.0 153 0 0.00 P-2 8"FIRE SVC WTR SVC 8.0 Ductile Iron 130.0 3 0 0.00 P-3 8"WTR SVC TEE - (02) 8-IN 8.0 Ductile Iron 130.0 21 -98 0.62 P-R-1 R-1 EX. HYDRANT #1051 12.0 Ductile Iron 130.0 1 98 0.28 P - FIRE SVC 6"FIRE SVC FIRE SVC CONNECT 6.0 Ductile Iron 130.0 248 0 0.00 P - WTR SVC 6"WTR SVC WTR SVC CONNECT 6.0 Ductile Iron 130.0 247 98 1.11 B26-010 Kagy LIHTC Water Model.wtg WaterCAD [24.00.03.22] 5/5/2026 Page 1 of 1 Pipe velocity at Peak Hour Demand PHD