The raised portion of the San Vicente Dam. Photo courtesy San Diego County Water Authority
The raised portion of the San Vicente Dam. Photo courtesy San Diego County Water Authority

The recently expanded San Vicente Reservoir could become a backup source of electric power under a plan being considered by the San Diego County Water Authority and the City of San Diego.

The agency and city, which owns the reservoir, are studying a 500-megawatt pumped-storage project — big enough to power a quarter million homes during periods of high electrical demand.

An official request was issued Wednesday to utilities, developers and investors potentially interested in the project with response expected by Feb. 15.

The project would consist of a pumping system between the existing San Vicente Reservoir and a new, smaller reservoir located uphill. The pumping system would be used during off-peak periods to pump water from the existing reservoir to the new upper reservoir. That water would then be released to power generators during periods of high demand.

“When we filled San Vicente Reservoir last summer, we filled it with more than just water — we filled it with huge potential for energy benefits,” said Mark Muir, chair of the water authority board. “Given this new potential for energy from a recently expanded water resource, it’s only prudent to continue to research the potential benefits to our region’s ratepayers.”

The water authority currently operates a pumped storage facility at Lake Hodges that can generate up to 40 megawatts of electricity.

Chris Jennewein is Editor & Publisher of Times of San Diego.