EBMUD Walnut Creek Raw Water Pumping Plants electrical safety improvements project - Turning a bad situation into an opportunity (case history)

Abstract

In February 2011, construction had just begun on a planned electrical safety improvements project at the East Bay Municipal Utility District's Walnut Creek Raw Water Pumping Plants (WCPP Nos. 1&2) when the electrical substation powering the facility was destroyed by a fault. This was followed a month later by a flood that completely filled the building that houses WCPP Nos. 1&2, submerging six large synchronous motors, pumps, and related electrical distribution equipment. These nearly simultaneous catastrophic events dramatically expanded and redefined the scope of the planned work. An immediate priority was to rebuild the electrical substation within 12 months so that the District could restore power to the undamaged WCPP No. 3 in order to meet anticipated summer pumping demands. A longer-term priority was to completely rebuild the pumps and motors, and replace the station service motor control centers, switchgear lineups, controls, and heating, ventilation and air conditioning system at WCPP Nos. 1&2 within the next 24 months. This paper presents how these two incidents happened and discusses how they were turned into an enhanced safety design opportunity.