By Associated Press
Power has been restored after California ordered the first rolling outages in nearly 20 years when a statewide heat wave strained the electrical system.
The California Independent System Operator (California ISO), which manages the power grid, declared an emergency Friday evening and directed utilities around the state to shed their power loads.
The state’s three biggest utilities — Pacific Gas & Electric /zigman2/quotes/202583141/composite PCG +4.69% , Southern California Edison and San Diego Gas and Electric — turned off power to more than 410,000 homes and businesses for about an hour at a time until the emergency declaration ended 3 1/2 hours later.
The move came as temperatures around the state hit triple digits in many areas, and air conditioning use soared.
The power grid is mostly stressed during the late afternoon and early evening because of higher demand and solar energy production falling. The state tried to prepare for the expected rise in electricity use by urging conservation and trying to buy more power. But a high-pressure system building over Western states meant there was less available.
A power outage caused a pump to fail at a wastewater treatment plant in Oakland, resulting in a sewer backup and the release of some 50,000 gallons of raw sewage into a waterway, the East Bay Municipal Utility District said.
The district said the outage began around 5 p.m. Friday, more than an hour before the rolling outages occurred, and sewage began to spill early Saturday. The agency said the sudden outage affected its ability to connect to backup power at the plant and during that time, workers were dealing with flooding while trying to restore power.
The agency warned boaters to stay away from the Oakland Estuary as it investigates the accident.
The state remained gripped by the heat wave Saturday, and the power grid operator will decide whether to continue the rolling outages on a day-to-day basis, California ISO spokeswoman Anne Gonzales said.
“We’re dealing with weather, clouds, wildfires ... these are quickly evolving situations, quickly changing,” Gonzales said.
The last time the state ordered rolling outages was during an energy crisis in 2001. Blackouts occurred several times from January to May, including one that affected more than 1.5 million customers. The cause was a combination of energy shortages and market manipulation by energy wholesalers, infamously including Enron Corp., that drove up prices by withholding supplies.
Counties up and down the state reported scattered outages, although the city of Los Angeles, which has its own power generating system, wasn’t affected.
The heat wave brought dangerously high temperatures, increased wildfire danger and fears of coronavirus spread as people flock to beaches and parks for relief. A thunderstorm rolling from the Central Coast to inland Southern California also brought dry lightning that sparked several small blazes, wind and flash flooding in the high desert.
Temperatures were expected to peak above 110 degrees (43 Celsius) in inland regions of state Saturday. The sweltering weather was expected to continue into Wednesday across greater Los Angeles, the Central Valley, Sierra Nevada foothills and parts of the San Francisco Bay Area.
Santa Clara, Alameda and Contra Costa counties opened cooling centers that will welcome people this weekend from the afternoon to the early evening. San Francisco officials said the city is recommending people stay home and that if the heat indoors gets intolerable to go outside to a shady place where they can stay cool and distant from other people.