Soaring temperatures, sagging power lines and unusually high demand for electricity shared the blame Sunday for an outage that cut power to 4 million customers across the West, one of the most severe in U.S. history.
In all, nine states from Oregon to Southern California and as far east as Texas had to deal with outages that began Saturday afternoon, turning traffic lights and movie screens dark and shutting down amusement park rides. Even parts of Mexico were affected, and the problems weren’t resolved until early Sunday.
The second major outage to hit the West in six weeks was a “cascading event,” said Dulcy Mahar of the Bonneville Power Administration in Portland. “You have a trigger incident and other things happen.”
Officials at the Western System Coordinating Council, an industry group of 88 Western power companies and marketers, confirmed the outage began in the Pacific Northwest but said they still are investigating exactly what happened.
Mahar said problems began at 2 p.m. Saturday, about two hours before widespread outages became evident. Temperatures in the 90s in parts of Oregon and Washington wilted power lines, some of which sagged into trees and shut themselves off. The result was fewer lines carrying an unusually high load of electricity, weakening the Pacific Northwest’s power grid.
Although power was restored to most if not all customers by early Sunday, there were lingering problems.
Los Angeles County senior lifeguard Chuck Moore said a 10-mile stretch of beach was closed because of a 6 million-gallon sewage release from the nearby Hyperion Treatment Plant. The problems were caused by the power failure.
County health officials are testing the water and are to report their results today, Moore said. Until the water is deemed safe, posted signs will warn beach-goers to stay out of the water.
At Disneyland, some visitors were evacuated from the park’s rollercoaster rides, such as Space Mountain, Big Thunder Mountain and the Matterhorn.
“We had regular power resume almost instantaneously,” park spokesman Joe Aguirre said. “But it caused certain attractions that use computers and such to shut down.”