About 20,000 Pacific Gas & Electric Co. customers in Sonoma County could briefly lose power Wednesday night as crews complete repairs to equipment that caused an outage in Petaluma earlier in the day, the utility said.
PG&E expects to switch those customers back to their normal power source sometime between about 8 and 10 p.m., spokesperson Megan McFarland said. The change could cause a temporary outage lasting less than 20 minutes.
PG&E outage map: Bay Area shutoff details by address
The work stems from an equipment problem on a PG&E transmission line that knocked out power to about 3,500 customers in the Petaluma area Wednesday morning, McFarland said.
Crews restored electricity to about 2,000 of those customers by moving them to an unaffected line, she said.
To safely repair the transmission equipment, PG&E later transferred roughly 20,000 customers to a different power source, McFarland said. That switch caused another short-lived interruption Wednesday afternoon.
"We expect to finish the repairs later this evening, and then we will move those 20K customers back to their original source," McFarland said. "This could cause another momentary outage."
PG&E alerts showed several Sonoma County outages affecting thousands of customers beginning shortly before 3 p.m.
Those alerts were consistent with PG&E's description of the temporary switching operation.
PG&E's broader grid-status page showed no systemwide supply constraints Wednesday.
Petaluma police reminded drivers Wednesday to treat any intersection with a dark traffic signal as a four-way stop.
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This article originally published at About 20,000 PG&E customers could briefly lose power tonight in Sonoma County.