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<br />I <br /> <br />I <br /> <br />I <br /> <br />ting tude could be installed at shallower depths if it is made self- <br /> <br /> <br />draining when the pump is not in operation. Extreme caution should <br /> <br /> <br />be exercised in designing and installing such a system to assure a <br /> <br /> <br />frost free operation. A typical main water circulation system is <br /> <br /> <br />presented in Figure-12. <br /> <br />I <br /> <br />I <br /> <br />I <br /> <br />Because of the large range of elevations that the district serves, each <br /> <br /> <br />zone has areas where adequate pressures are a problem. The range of pressures <br /> <br /> <br />that was considered desirable was 40 to 100 psi in the water main. A pressure <br /> <br /> <br />of 40 psi in the main would be as low as 30 psi in a house after the water <br /> <br /> <br />traveled through the service line, house fittings, and vertically up one or <br /> <br /> <br />two stories. The pressure of 100 psi and over causes line leakage to increase <br /> <br /> <br />and also requires home owners to use a pressure reducing valve to protect plumbing <br /> <br /> <br />and certain appliances. Figure-6 and -7, Pages 30 and 31 show the area within <br /> <br /> <br />each pressure zone that exceed these pressure limits. In an area where pres- <br /> <br /> <br />sures are below 40 psi, it is recommended that pressure be boosted. Where <br /> <br /> <br />pressures exceed 100 psi, pressure. reducing valves are recommended in locations <br /> <br /> <br />that will not disrupt normal operation within the zone. <br /> <br />I <br /> <br />I <br /> <br />I <br /> <br />I <br /> <br />I <br /> <br />Also included with the pressure problem are the wells that are pumping direct- <br /> <br /> <br />ly into the distribution system. In order to control the extremely high and <br /> <br /> <br />low pressures in Zones Band C, lines running directly from the wells to the <br /> <br /> <br />storage tanks are recommended. This would allow pressure reducing valves to <br /> <br />be installed in Zone B and a booster pump to be installed in Zone C. The direct <br /> <br /> <br />lines from the wells to storage tankS would also allow a longer chlorine contact <br /> <br /> <br />time for the water (2 hours recommended) before going into the distribution system <br /> <br /> <br />and provide better circulation in the storage tanks. <br /> <br />I <br /> <br />I <br /> <br />I <br /> <br />I <br /> <br />The following improvements are recommended to upgrade the existing distribu- <br /> <br />tion system to a more desirable level. Replacement and lowering of lines <br /> <br /> <br />(long term solution) and the installation of mineral insulation cable (short <br /> <br /> <br />term solution) has been recommended for those locations were freezing has <br /> <br /> <br />historically been a problem. Additional gate valves and pressure reducing <br /> <br /> <br />valves are also suggested. <br /> <br />I <br /> <br />I <br /> <br />I <br /> <br />I <br /> <br />-5~- <br />