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3.2.3 I Gem Lake -- White Bear Township Available Fire Flow As with the White Bear Lake fed Gem Lake system modelling, available fire flow in this report is defined as the flow capacity at a point in the water distribution system which causes the pressure to fall to 20 psi residual pressure. As discussed in Section 3.2.1, some areas of Gem Lake are predicted to already experience pressures close to 20 psi without a pressure booster station, so as would be expected the available fire flow for the higher elevation areas are low as shown in Appendix G-3. A pressure booster station would be required to provide adequate fire flows throughout Gem Lake. Running the model with the booster station scenario, available fire flows were analyzed as shown in Appendix G-5. As can be seen in Appendix G-5 a pressure booster station can provides Gem Lake with adequate fire flows. 4 Future Water System Co *rations Currently the residents and businesses within Gem ake receive water supply from varying sources. Similar to the 2006 Municipal Water Supply Feasibility Study, this water supply feasibility study evaluates the potential for a centralized water distribution system within Gem Lake with water provided by a single source. Per direction provided by the City, the scenarios explored in this study included water supply connections to either the White Bear Lake or White Bear Township systems. For the purposes of this feasibility study, the systems modeled evaluated ability to serve Gem Lake from a single connection to either the White Bear Lake or White Bear Township systems. Once purchased and delivered into the Gem Lake system, maintaining water quality and adequate system pressures and flow will be the responsibility of Gem Lake. While modeling showed a single connection to be adequate to serve Gem Lake, multiple connections to whichever City will be supplying water are recommended to be further explored in subsequent design phases in order to provide redundancy and operational flexibility. One of the key benefits of a single source for a centralized water supply system is the ability to provide a looped watermain system, minimizing distribution system piping dead ends and the associated potential concerns for water quality issues. Although ideal to provide a looped system, as shown by the 10-inch watermain loop in the scenarios modeled, there is the potential to provide connections to multiple neighboring systems as long as these service areas remain separate. For example, the commercial area on the east side, currently connected to the White Bear Lake system, could potentially remain fed by White Bear Lake while a separate looped watermain system fed by White Bear Township could be constructed for the residential areas of city. The scenarios modeled for this feasibility study assumed that all service connections with the City would be fed with water from the new centralized water distribution system. Existing services in the City currently fed by other communities are assumed to be replaced with new service connections. In previous studies. as discussed in the 2020 City of Gem Lake Comprehensive Plan, the City also evaluated a potential water system scenario based on three potential water service areas, each one being served by the nearest surrounding community's distribution system. The end result of this scenario would be three separate water systems in the City, with the east side being fed by White Bear Lake, the north side being fed by White Bear FEASIBILITY STUDY UPDATE City of Gem Lake, MN Page 9