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HomeMy WebLinkAbout011_Water Engineering ReportEngineering Report Water Main Extension 701 N. Ferguson Avenue February 2023 Submitted to: City of Bozeman Engineering Department 20 East Olive Bozeman, MT 59715 Prepared by: Stahly Engineering and Associates 851 Bridger Drive, Suite 1 Bozeman, MT 59715 (406) 522-8594 Water Mains 1 2/17/2023 Engineering Report Contents Note: The Engineering Report format follows DEQ-1 organization. Additional information required by the City of Bozeman Design Standards is added where required. Report Narrative 1.1.1 General Information 1.1.2 Extent of Water Works System 1.1.3 Alternate Plans 1.1.4 Site Conditions 1.1.5 Water Use Data 1.1.6 Flow Requirements 1.1.7 Sources of Water Supply 1.1.8 Proposed Treatment Processes 1.1.9 Sewage System Available 1.1.10 Waste Disposal 1.1.11 Automation 1.1.12 Project Sites 1.1.13 Financing 1.1.14 Future Extensions Figures and Tables Figure 1. Vicinity Map Figure 2. Water Plan Table 1. Domestic Water Design Flow Table 2. Estimated Domestic Water Demand Water Mains 2 2/17/2023 1.1.1 General Information The proposed Trinity Church development is located northwest of the intersection of Durston Road and Ferguson Avenue. The proposed project consists of a 2- phase site plan to construct a church and related accessory facilities. Phase 1 will include initial construction of the church’s administrative offices and meeting areas, with Phase 2 including a large addition to the building primarily consisting of a formal worship facility. The project is proposed on the currently undeveloped 8.818 acre Lot 1 of Diamond Estates Subdivision Number 2 Phase 1 at 701 N. Ferguson Ave. The proposed building will be constructed in two phases, and will consist of typical uses for a church of this size. Phase 1 will consist of 10,100 square feet of floor space containing a ministry center and offices for church staff. Phase 2 will include 30,565 square feet of floor space and will include classrooms, a nursery, and a large fellowship hall for worship services. Each phase will include associated parking, sidewalk, signage, landscaping, etc. to serve the function of the building. The project will be served by extension of City of Bozeman water mains through the northern parking area of the project. City of Bozeman water mains currently exist in several locations adjacent to the project. Currently, a 10” main exists to the east in Ferguson Avenue, and a 12” main runs along Durston Road to the south. The Owner’s contact information is: Gallatin Valley Presbyterian Church a/k/a “Trinity Church” 4720 Classical Way Bozeman, MT 59715 Water supply and wastewater treatment will be provided by the City of Bozeman’s municipal systems. The system owner’s contact information is: City of Bozeman Public Service Department PO Box 1230 Bozeman, MT 59771-1230 The location of the Trinity Church Development site is shown on the Vicinity Map in Figure 1. Water Mains 3 2/17/2023 Figure 1. Vicinity Map, Bozeman, Montana 1.1.2 Extent of Water Works System Water supply is readily available around the project due to the existing development. A 10” water main runs in Ferguson Avenue to the east, with a 12” main running along Durston Road to the south. There is an existing fire hydrant to the east of the project at the intersection of Diamond Street with Ferguson Avenue. The site falls at the boundary of pressure zones within the Bozeman distribution system. Two sets of pressure reducing valves are adjacent to the site near the southeast and southwest corners. Service to Trinity Church will be provided by extension of a new 8” main in the northern parking area of the development. The new main will extend approximately 350 feet west, where it will terminate in a blowoff hydrant. The City has indicated that this arrangement is preferable to a looping main connecting with Durston, as the project is located on the border of the Northwest and South pressure zones for the City’s water distribution system. The Church building will connect to this main extension for domestic water and fire service. When the second phase of the building is constructed, it is anticipated that a fire hydrant will be installed just south of the building by tapping into the Durston main. The full extents of the existing and proposed water system can be seen in the attached Figure 2 “Water Plan” included at the end of this report. Water Mains 4 2/17/2023 Irrigation will be supplied by a well to be drilled to the west of the Phase 1 building. The development’s water main extension has been designed in accordance with Montana Department of Environmental Quality Circular 1, and the City of Bozeman Design Standards and Specifications Policy. Construction specifications will be Montana Public Works Standards and Specifications (MPWSS), and the City of Bozeman Modifications to MPWSS. New water main will be in 60’ wide street easement along the Diamond Street right-of-way extending through the property. 1.1.3 Alternate Plans Due to the project’s location within the City of Bozeman, extension of public mains was the only water supply alternative. Distribution alternatives were explored, such as looping mains. However, due to this projects location on the boundary of two distribution pressure zones, connecting the mains in Durston and Ferguson is not desired by the City. The design was chosen as the best fit with the site’s constraints and requirements. 1.1.4. Site Conditions The Trinity Church Development Project is located at the northwest quadrant of Durston Road and Ferguson Avenue. The 8.818 acre lot is currently undeveloped. Adjacent development consists of single family residential developments to the north, east, and south. Immediately to the west of the site is Christ the King Lutheran Church, which closely resembles both the proposed type and scope of development of this project. On the north of the site, a 10’ paved pedestrian path is proposed to facilitate pedestrian transportation through the site from the surrounding residential areas. Due to the adjacent residential development, utility connections are readily available for connection around the site. The Vicinity Map, seen in Figure 1 towards the beginning of this report, shows the location of the proposed development in relation to the existing development in the area. The site is not located within the 100-year floodplain. 1.1.5. Water Use Data Water Mains 5 2/17/2023 Domestic water will be provided by the City of Bozeman Municipal system. This project is located within the planned service area of the City’s system. Estimated water use for the Trinity Church development has been determined utilizing values provided in City design standards and Facility Plans and is shown in Table 1. For water main sizing, typical City design flows are utilized. Because the water system will not supply irrigation, large summer peaks are not anticipated. The classroom, office, and community center are each estimated to generate 30 gpd for each 1000 sf of space. The sanctuary and fellowship hall are each estimated to use 3 gpd/seat. A peaking factor of 6 was used to determine the peak hour flow rate. The estimated total project design flow is 2,955 gpd with a peak hour flow of 12.3 gpm. Table 1 – Estimated Sewer and Water Use and Demands Estimated Water and Sewer Use and Demands Phase One #Units Unit Gpd/1000 sf Gallons/day Office Space 3600 sf 30 108 Community Center 7500 sf 30 225 Phase Two #Units Unit Gpd/Unit Gallons/day Classroom 5500 sf 30 165 Sanctuary 648 seat 3 1944 Fellowship Hall 171 seat 3 513 Total Domestic Use 2,955 Average Day Demand (gpm) 2.05 Peaking Factor 6.0 Total Annual Use (gallons) 1,078,575 Total Annual Use (ac ft) 3.31 Peak Hour (gpm) 12.3 Irrigation will be provided by a new well located just west of the building as shown on Figure 2. Irrigation lines will provide water to site landscaping and will be maintained by the property owner. Cash in Lieu of Water Rights (CILWR) CILWR fees are assessed within the City of Bozeman based on estimated water use for a project. Currently, a $6,000 fee is assessed per acre- ft/year. At full build-out, the annual domestic consumption is estimated to be 3.31 acre feet, which translates to an estimated $19,860 CILWR. Looking only at the Phase 1 portion of the building (approx. 12,000 SF), the total domestic use is 333 gpd (0.23 gpm). Applying a peaking factor of 6.0, results in a total annual use of 121,545 gallons, or 0.37 ac-ft. This amount would require $2,220 CILWR. Water Mains 6 2/17/2023 1.1.6. Flow Requirements As stated previously, the peak hour water demand is estimated to be 12.3 gpm. Fire flows have not been determined yet but will be in accordance with the Uniform Fire Code. It is anticipated that a fire flow of 1500 gpm will be required. The fire flow requirement will be the dominant design constraint for system design. A hydrant flow test was conducted near the site as part of the City’s 2017 Water Facilities Plan. Test number 8 was performed northeast of the site near the intersection of Ferguson Avenue and Renova Lane. This test resulted in a static water pressure of 67.4 psi, with a residual pressure of 57.7 psi at a flowrate of approximately 2500 gpm. Based on this test, the water system in this area can provide fire flows and peak domestic demand with little effect on system pressure. A hydrant flow test will be conducted in closer proximity to the site prior to final design. The 2017 City of Bozeman Water Facility Plan did not identify any fire flow capacity limitations in this area. 1.1.7. Sources of Water Supply This section is not applicable. 1.1.8. Proposed Treatment Process This section is not applicable. 1.1.9 Sewage System Available Sewer service is provided by new City mains extended through the site from the existing sewer main in Ferguson Avenue. Any sewer main or service crossing will be designed in accordance with COB separation requirements. 1.1.10 Waste Disposal This section is not applicable. 1.1.11 Automation Water Mains 7 2/17/2023 This section is not applicable. 1.1.12 Project Sites This section is not applicable. 1.1.13 Financing This section is not applicable. 1.1.14 Future Extensions The water main extended into this property could be extended west in the future, as the City has a street easement traversing the tract, and may require looping for subsequent developments. >>>>>>> > > >>>>>>47804777477647754774477347 7 2 4771477 0 47694768 4767 47664769477047714772FOPTFOPTFOPTFOPTFOPT FOPTFOPTFOPTFOPTFOPTFOPTFOPTFOPTFOPTFOPTFOPTFOPTFOPTFOPTFOPTFOPTFOPTFOPTFOPTFOPTFOPTFOPTFOPTUGCUGCUGCUGCUGCUGCUGCUGCUGCUGCUGCUGCUGCUGC UGC UGCUGCUGCUGCUGCUGCUGCUGCUGCUGCUGCUGCUGCUGCUGCUGCUGCUGCUGCUGCUGCUGCUGCUGCUGCUGCUGCUGCUGCSSSSSSSSSSSS SS SS SS SS SS SS SS SS SS SS SSSSSSSS SSSSSSSSSSSSSSSSSSSSSSSSSSGASGASGASGASGASGASGASGASGASGASGASGASGASWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWW WWSDSDSDSDUGE UGE UGESS WW PHASE 1PHASE 2SSSSSSWWWWWUPSD8'8'[][][]>>>>1 10/13/2022 SITE PLAN SUBMITTAL ZWL CDP 2 10/31/2022 PRELIM. BID/PERMIT SET ZWL CDP 3 2/17/2023 INFRASTRUCTURE SUBMITTAL ZWL CDP PROFESSIONALENGINEERS &SURVEYORSSTAHLYENGINEERING& ASSOCIATESTRINITY CHURCHMINISTRY CENTERSITE PLAN 701 N FERGUSON AVEBOZEMAN, MT 59718FIGURE 2WATER PLAN