The scheduled three-day closure of the Bay Bridge has begun.
At 7:57 p.m. Friday night Chopper 11 flew above the San Francisco side of the bridge.
Police and CalTrans crews were seen blocking off the eastbound side so that no cars could drive through.
At 8:05 p.m. Chopper 11 had traveled to a position above the MacArthur Maze, where police had blocked off that roadway so no vehicles could pass.
A few cars trickled through before that and were allowed to pass to the other side. Complete shut down was complete by 8:30 p.m.
The shutdown could undermine attendance at several high-profile events planned this weekend.
The closure could affect several events including an art festival in Sausalito, a UC Berkeley football game and a free concert in Golden Gate Park to commemorate the 40th anniversary of the Summer of Love.
There is also a Cal game against Tennessee.
The bridge is being shut down from 8 p.m. Friday until 5 a.m. Tuesday to give construction workers time to make progress on replacing a section of the span that was damaged during the 1989 Loma Prieta earthquake.
On Wednesday night, workers tested hydraulic jacks. Two of 16 did not work. Caltrans said the problems were fixed, and the jacks will be ready for the closure.
Travelers will have to take public transportation or use other bridges to cross the bay.
Caltrans has spent $1 million on a statewide campaign to warn motorists about the bridge closure.
Caltrans also enlisted the help of 40 people in St. Anthony's re-entry program, who have been passing out bridge closure fliers for the last three weeks.
"I was living in the Tenderloin. I was a substance abuser," said Roderick Turner. "This job came right as I had the opportunity to seek employment. It was just heaven sent."
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