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I I I I I I I I I I I I I I I I I I I The hydraulic model provided the actual flow rate required from each pump station, which depends on elevation and discharge pressure at each of the stations. Because of the service area layout and elevation changes, the north pump station requires less discharge pressure than both the middle and south stations. Intake System An intake screen constructed of expanded metal will be located in the storage reservoirs and help prevent large debris from entering the pump system. A pipe will connect the intake screen to a concrete wet well located below the pump system and building. An isolation gate valve on the intake pipe will provide isolation during maintenance and cleaning of the wet well. Each pump station will include multiple pumps to provide a range of required flow rates from incidental watering needs to the peak day demand. The stations will be designed as prefabricated, skid-mounted pump stations including all pumps, motors, valves, filters, and controls. The pump systems will consist of multiple vertical turbine pumps capable of supplying the required peak season flow rate at the set pressure. The smaller pumps will be installed to keep the distribution system pressurized and to meet small demands. The main pumps will be controlled by variable frequency drives (VFD) to provide constant pressure to the system. The pump system will be designed as a pre-fabricated, skid-mounted system including the main pumps, pressure maintenance pumps, variable frequency drives, piping, valves, and electrical controls. Automatic filtration will also be included on the skid, downstream of the pumps. This filter will prevent debris from entering the irrigation systems and help avoid clogging sprinklers or valves. The automatic filtration system will backwash debris from the filter screen. Typically, this water is discharged back into the storage reservoir, away from the intake screen. North (Proposed) Pump Station The North pump station will be located at the proposed new storage reservoir (described in previous sections of this report). Output from the hydraulic model requires approximately 7,400 GPM at a discharge pressure of 74 PSI. The total required horsepower is anticipated to be approximately 540 HP. Middle (Timnath) Pump Station The Middle pump station, located at a new reservoir adjacent to the existing Timnath reservoir, will have a discharge flow rate of approximately 11,300 GPM at a discharge pressure of 90 PSI. The total required horsepower is anticipated to be approximately 990 HP. South (Lake Canal Res. #1) Pump Station The South pump station will pump water from the existing Lake Canal Reservoir #1 at a flow rate of approximately 11,700 GPM and a discharge pressure of 116 PSI. The total required horsepower is anticipated to be approximately 1,290 HP. Aqua Engineering, Inc. June 7,2004 Canal Modernization Feasibility Study - 15-