TO:
Honorable Mayor and Members of the City Council
THROUGH:
David N. Carmany, City Manager
FROM:
Jim Arndt, Public Works Director
Raul Saenz, Utilities Manager
Brian Wright, Water Utility Supervisor
SUBJECT:Title
Plans and Specifications for the Block 35 Variable Frequency Drive Booster Pump Replacement Project and Authorization to Solicit Construction Bids.
APPROVE
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Recommended Action
RECOMMENDATION:
Staff recommends that the City Council:
a) Approve the plans and specifications for the Block 35 Variable Frequency Drive Booster Pump Replacement Project; and
b) Authorize the City Manager to solicit construction bids.
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FISCAL IMPLICATIONS:
Funds in the amount of $32,000 are budgeted in the 2012/2013 Public Works Water Pumping budget.
BACKGROUND:
The City of Manhattan Beach Public Works Department operates four (4) booster pumps at the Block 35 Water Plant Facility to maintain adequate potable water supply and pressure for residential use and fire protection. Each of the four booster pumps is driven by electrically powered motors equipped with Variable Frequency Drives (VFD), enabling pump speed adjustments to be made via the City’s SCADA System based on water demand, which varies through the course of the day.
DISCUSSION:
Of the four booster pumps located at the Block 35 Booster Station, one has suffered a complete VFD failure as the result of a dead short in the electrical distribution circuitry and must be operated in “manual by-pass” mode (100% speed). It has been determined through detection of fatigue and stress cracks in the VFD electrical distribution circuitry of each pump that failure is imminent for the remaining three booster pump motor VFDs, each of which has been temporarily repaired to allow for continued operation.
If approved by City Council, Staff would proceed to advertise the project for construction bids. Bids will be opened and analyzed in mid- A...
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