The prospect of wide-ranging electrical shutoffs to prevent wildfires is leading Napa to bulk up on its backup power supplies – to help keep the water flowing if the city goes dark.
Three new mobile generators will provide emergency power to some of Napa’s nine pumping stations in its water network, which serves more than 25,500 customers around and just outside the city of about 80,000 people.
Napa’s city Water Division will use the generators to maintain service in hilly areas that rely on pumps, utilities director Phil Brun wrote in a memorandum to the council.
The three water treatment plants serving Napa are equipped with fixed generators that automatically switch on when power is interrupted.
The new equipment will join three existing mobile generators already used to keep pump stations running during outages.
The $305,000 purchase, which the City Council approved Tuesday, is Napa’s latest response to Pacific Gas & Electric Co.’s warnings that it may pre-emptively shut off electricity as a fire-safety measure during periods of high temperatures and strong winds in the North Bay, where firestorms in October 2017 killed more than 40 people and left behind billions of dollars in property damage.
California’s Public Utilities Commission in May allowed PG&E and other power companies to stage “public safety power shutdowns” that could disrupt service to thousands of customers at a time during extreme fire risk. PG&E gas said such drastic shut-offs would take place when a combination of strong winds and dry vegetation raise the chances of downed electrical lines triggering infernos like the Camp Fire, which killed 85 people in November and wrecked most of the Butte County town of Paradise.
After a large-scale power cut, PG&E might not restore service for 24 to 48 hours while it inspects utility lines for damage, Napa County Supervisor Diane Dillon said at a community preparedness meeting in St. Helena in April.
The upper Napa Valley experienced its first pre-emptive shut-off in October 2018, when more than 5,700 homes and businesses in Calistoga, Lake Berryessa and other communities went dark for up to a day.
PG&E de-energized Upvalley wires after forecasts of low humidity and wind gusts reaching 50 mph, combined with vegetation left parched by several rainless months from late spring through the summer. The disruption shut down Calistoga’s downtown business district and local public schools.
A second local safety shutdown took place June 8, when PG&E cut off power to about 1,300 county customers, mainly around Lake Berryessa.