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Water Storage Siting Study City of Lino Lakes WSB Project No. 2988-44 Page 12 5. IDENTIFICATION AND ANALYSIS OF POTENTIAL LOCATIONS 5.1 Site Identification Potential sites for constructing a 1.5 MG composite water tower were identified for further analysis based on location in the distribution system, ground elevations, and potential for ownership. A range of geographical locations were selected and modeled to gain a more complete understanding of the implications on the distribution system. Five initial sites were considered and discussed with City staff. Three of the sites on the west side of the City were eliminated due to hydraulic balancing concerns and their proximity to Tower One. Two additional sites, both located centrally in the water distribution system, were selected for further analysis as properties that the City could potentially acquire. The final sites that were analyzed are shown in Figure 2 and summarized below in Table 9. Table 9. Water Storage Sites Analyzed Site Location Approximate Ground Elevation Nearest Watermain Diameter Ownership Site 1 Birch St. and Timberwolf Tr. 905 ft. 16 in. School District Site 2 Birch St. and 20th Ave. South 910 ft. 16 in. City Site 3 Birch St. and 12th Ave. South 900 ft. 16 in. Private – Agnes Lamotte Site 4 Birch St. and West Shadow Lake Dr. 900 ft. 16 in. School District 5.2 Site Analysis Each of the four identified sites was modeled with the City’s water distribution system using WaterCAD V8i. Extended period simulation scenarios were run in which the water demands were changed continuously over a duration of 24 hours as they would on a maximum demand day. The model attempts to provide a snapshot into how the water distribution system would respond on a high-demand day; it includes water tower levels, pump controls, and demand fluctuations. By adding a water tower to different locations, the model will provide critical information on how the towers will balance with each other when filling and draining. The model also assists in determining if an altitude valve will be required to allow each of the water towers to be filled to its maximum capacity. Model scenarios were run both with and without altitude valves at each tower. 5.3 Analysis Results Because of their relative proximity to each other and the well field, the modeling results did not show significant differences between the sites that were analyzed. The model showed larger fluctuations in water elevations for Tower One, and minimal fluctuations for Tower Two and future Tower Three. These results were anticipated as Tower One is located furthest from the well field, and Tower Two currently requires an altitude valve to allow Tower One to be filled to its maximum capacity. Fluctuations were minimized somewhat for Tower Three at Site 4, the site furthest to the west. It is anticipated that Tower Three, regardless of the site selected, will require an altitude valve to balance the system . The expected tower levels that would occur over the maximum day with Tower Three located at each of the four analyzed sites are included in Appendix A.