14 DPS Shutdown
The Distribution Pump Station is equipped with five pumps. Two pumps are variable speed and the other three pumps are constant speed. The lead/lag status of the two variable speed pumps is rotated monthly. The lead/lag status of the three constant speed pumps is also rotated monthly. The Distribution Pump Station transports filtered and disinfected water from the Reclamation Phase II Reservoir to the Golf Course for irrigation.
If any changes in pump operation are made outside of the normal monthly rotation schedule, the Operator must first verify that the Reclamation Phase II Reservoir demand and/or distribution flows are not at high levels. If possible, the Operator should wait until a period of low demand and flow before making any changes to pump operation at the Distribution Pump Station.
The combination of variable speed and constant speed pumps provide a wide range of flow requirements. Pump start/stop controls and sequencing are based on surge tank pressures and reservoir water levels and are, therefore, unaffected by the monthly rotation schedule.
- DPS: Distribution Pump Station
- If working on or near equipment, watch for rotating parts.
- Follow Lock Out/Tag Out procedures.
- Ensure that timing of the SOP does not interfer with the current Reclaimed Water demand and distribution.
- Verify operation of the Back-Up Pump. If the Back-Up Pump is inoperable, the WWTP will not have a Reclaimed Water supply during the shutdown period.
- Frequent switching on and off of variable speed pumps can damage the VFDs.
- If the system pressure is not maintained (by closing the Surge Tank Flow Control Valve, step 1.a) while performing this SOP, it will take much longer to bring the system back online.
The Equipment List/Tag No. List describes the Reclaimed Water System as the "Recycle Water System".
- Operator I
- Knowledge of Distribution Pump Station System
- Knowledge of Reclamation Phase II System
- Knowledge of SCADA controls
If pump operation is changed outside of the normal monthly rotation, the operator must ensure that the system is not running the Water Reclamation Phase II Reservoir (Golf Course) and that distribution flows are not high. Switching variable speed pumps on and off can damage the VFDs. Wait for a relatively low distribution flow before changing pump operation. 1. Maintain system pressure. a. Close the Surge Tank {tag no. 1404TNK4691} flow control valve {tag no. 1404FCV4691}. This will maintain pressure in the surge tank while the system is offline. 2. Turn off pumps. a. Turn the HOA switches {tag no. 1404HS4300, 1404HS4400 & 1404HS4500} on the constant speed pumps {tag nos. 1404PMP/MTR4300, 1404PMP/MTR4400 & 1404PMP/MTR4500} to OFF. b. Then the HOA switches {tag no. 1404HS4100 & 1404HS4200} on the variable speed pumps {tag nos. 1404PMP/MTR4300, 1404PMP/MTR4400 & 1404PMP/MTR4500} to OFF. 3. Close distribution valves. a. Close the Shoreline Distribution isolation valve {tag no. 1404VLV4681}. b. Close the Quinientos Distribution isolation valve {tag no. 1404VLV4681B}. 4. Complete system isolation and equipment shutdown. a. Open the control panel and locate the 15 amp breaker labeled Back-Up Pump {tag no. 1603PMP6100}, flip the breaker to OFF (the breaker is not tagged but is painted white and labeled "Power Loss Back Up" ). This will cause the Back-Up Pump to engage after 60 seconds and supply the treatment plant with reclaimed water. b. Close the El Estero Distribution isolation valve {tag no. 1404VLV4681A}. c. Turn OFF power to chlorine analyzers 1 and 2 {tag nos. 1301AE/AIT3446 & 1301AE/AIT3447}. d. Turn OFF Sample Pumps {tag nos. 1402PMP4300 & 1402PMP4400}. e. Lockout/Tagout the Distribution Pumps {tag nos. 1404PMP/MTR/VFD4100, 1404PMP/MTR/VFD4200, 1404PMP/MTR4300, 1404PMP/MTR4400 & 1404PMP/MTR4500}. f. Notify the Lab that the DPS is offline. Reclaim sampling will be affected by the shutdown. g. If the work that is being performed requires the isolation of a Distribution Pump, TagOut all affected valves. This will prevent errors when the system is restarted. |
- Update log book.
- Update maintenance records (if applicable).
- Report any maintenance or attention that is required.
- Minimal impact to the WWTP reclaimed water supply when transitioning from normal operation to the Back-Up Pump.
Notify Water Distribution that the demand for irrigation at the Golf Course cannot be met while operating under the Back-Up Pump.
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