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Technical Memorandum <br />Hydraulic Model Review <br />March 9, 2018 <br /> <br /> <br /> Page 4 of 5 <br /> <br /> <br />x Pressure Analysis – Average pressures shown in Figure 2A <br />- Area south of pump station experiences large pressure fluctuations of 20 <br />to 25 psi. This is an indication of inadequate capacity within the water <br />main feeding the new pump station. <br />- All other areas had adequate pressures. <br />x Fire Flow Analysis – Available fire flow at 20 psi residual shown in Figure 2B. <br />- Available fire flow south of the new pump station was greatly reduced <br />when the pump station was operational. <br />- Available fire flows in the TCAAP area were at least 8,000 gpm or greater. <br />Key items to note: <br />1. Results showed a 20 to 25 psi pressure drop with running one pump at the new pump <br />station to the area upstream of the pump station. This is a significant and noticeable <br />pressure drop due to the headloss and capacity deficiency in the existing water main <br />feeding the new pump station. <br />2. Fire flow capacity upstream of the pump station was also greatly reduced when the <br />pump station was operational. <br /> <br />Scenario 2A: Future System – New Pump Station/New Water Tower and TCAAP Water Main <br />with the addition of 12-inch Water Main along Snelling Avenue <br />Evaluation of the future system to determine pressures and available fire flow to <br />the TCAAP Area. The analysis included the following improvements: <br />1. Improvements listed under Scenario 2. <br />2. New 12-inch water main along Snelling Avenue. <br />3. Water demands were based on future planned growth to 2040. <br />x Pressure Analysis – Average pressures shown in Figure 2C <br />- With the addition of the water main along Snelling Avenue, the pressure <br />fluctuation was reduced to a range of 10 to 15 psi which showed a <br />significant improvement. <br />- All other areas had adequate pressures. <br />x Fire Flow Analysis – Available fire flow at 20 psi residual shown in Figure 2D. <br />- Available fire flow improved to the area south of the new pump station <br />with the addition of the Snelling Avenue water main. <br />- Available fire flows in the TCAAP area were at least 8,000 gpm or greater.