Residents and businesses in south Ventura County are being called to voluntarily reduce their water use beginning Sunday, Jan. 14, while a regional water treatment plant is upgraded and a large-diameter pipeline is repaired during a 14-day shutdown.

The Metropolitan Water District of Southern California joined the Calleguas Municipal Water District in making the precautionary water-saving request as Metropolitan prepares for the planned shutdown of its Joseph Jensen Water Treatment Plant and Foothill Feeder pipeline. The outage is scheduled to last until Jan. 27.

The Jensen plant in Granada Hills—one of five such treatment facilities within Metropolitan’s distributions system—is a significant source of drinking water for Ventura and Los Angeles counties. The 13-mile Foothill Feeder stretches from Castaic Lake to the Jensen plant, delivering state project supplies imported from Northern California through the California Aqueduct.

Although most local agencies affected by the shutdowns will have groundwater, reservoir supplies and other sources to meet retail demands during the outage, some pockets will need consumers to conserve water to stretch supplies, said Debra C. Man, Metropolitan’s chief operating officer.

“As a precaution, we’re asking consumers in the region to voluntarily conserve water whenever and wherever possible over the 14 days,” Man said.

Consumers—particularly in the cities of Camarillo, Moorpark, Oxnard, Simi Valley, Thousand Oaks and Port Hueneme and communities of Camarillo Heights, Fairview, Las Posas Valley, Oak Park, Santa Rosa Valley, Lake Sherwood, Point Mugu, and Somis — are asked to contact their local water supplier to determine water-use restrictions for their area.

While Metropolitan will upgrade and test the Jensen plant’s back-up emergency power generation systems during the shutdown, Foothill Feeder repairs are the primary reason for the outage, Man said. During the shutdown, Metropolitan plans to replace and repair sections of prestressed concrete pipe at three locations along the 21-foot-diameter pipeline.

“Maintaining and improving our ability to store, process and deliver drinking water throughout our Southern California service area requires periodic curtailments in deliveries while work is being done,” Man said.

Metropolitan routinely schedules shutdowns of its facilities in winter months, when temperatures usually are cooler and demands are lower, to complete inspections and perform maintenance and upgrades with the least impact on consumers.

Don Kendall, Calleguas general manager, said voluntary water conservation by consumers, combined with activation of system interconnections between water agencies, will offer safeguards that residents and businesses have adequate water during the shutdown.

“We, however, stand prepared to intensify the conservation request in the unanticipated event that locally stored supplies dwindle during the outage,” Kendall cautioned. “Residents who want to know more about how the shutdown will affect them should contact their local water provider directly.”

Kendall added that the quality of tap water may be impacted to varying degrees within the Calleguas service area because the reduction in imported water deliveries may require increased use of groundwater within the region.

“As more local groundwater is pumped, some water users may notice a change in the
aesthetics of their tap water,” Kendall said.

The Metropolitan Water District of Southern California is a cooperative of 26 cities and water agencies serving 18 million people in six counties. The district imports water from the Colorado River and Northern California to supplement local supplies, and helps its members to develop increased water conservation, recycling, storage, and other resource-management programs.