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2.2 <br />Table 3 — Water System Static Pressures <br />verage Da <br />Demand <br />aximum Day <br />Demand <br />Peak Hou <br />Demand <br />Minimum Pressure (psi) <br />56 <br />56 <br />56 <br />Average Pressure (psi) <br />68.5 <br />68.1 <br />67.5 <br />Maximum Pressure (psi) <br />77 <br />77 <br />76 <br />Demand (gpm) <br />1,221 <br />3,330 <br />5,498 <br />All three demand scenarios were done with the towers at an HGL of 1,031 feet. No wells were <br />running during the model simulation. <br />Existing System 24-Hour Simulation <br />A 24-hour extended period simulation was run for average day demand (ADD) and maximum day <br />demand MDD to model how the existing system performs in terms of pressure, velocity, and tank <br />levels. System pressures are recommended to be in the range of 35 psi to 80 psi, and pipe <br />velocities are recommended to not exceed 5 feet per second. For an average day demand, 1.72 <br />MGD was assumed, and for maximum day demand, a maximum day peaking factor of 2.73 was <br />assumed to get a maximum day demand of 4.7 MGD. For both demand scenarios, diurnal <br />demand curves were used, and were developed by analyzing SCADA operation data <br />documenting system water tower levels, as well as using industry standards and previous <br />experience. These diurnal demand curves are shown in Figures 1 and 2 and were used for all <br />modeling simulations. The operating range of Tower 1 was assumed to be 6 feet where wells <br />would initially turn on when the HGL of Tower 1 went below 1,025 feet, and the wells would turn <br />off when the HGL of Tower 1 went above 1,031 feet. Figures 4-5 in Appendix B show the <br />operation of the wells and towers for both demand scenarios. <br />The pressures across the system were generally consistent throughout the 24-hour simulation for <br />both demand scenarios. As can be seen in Figures 6-7 in Appendix B, at no point did pressures <br />drop below 50 psi, and at no point did pipe velocities exceed 3 feet per second for the ADD <br />simulation or exceed 5 feet per second for the MDD simulation. In fact, only one segment of pipe <br />exceeded 4 feet per second during the MDD simulation. <br />FEASIBILITY STUDY RAMSY 154354 <br />Page 5 <br />