Bay Area freeways, especially those leading to the San Francisco-Oakland Bay Bridge, saw an increase in traffic Friday on the first day of a BART strike, the California Department of Transportation reported.
Bay Area traffic delays increased around 30 percent above normal between 5 and 10 a.m., according to Caltrans spokesman Bob Haus.
The largest increase was seen on Interstate Highway 80 in Alameda and Contra Costa counties, Haus said.
Interstate Highways 580 and 880 saw delays around twice as high as normal around 7 a.m., and the carpool lane on Interstate Highway 80 leading up to the Bay Bridge saw around 50 to 100 percent more traffic than a typical Friday, Haus said.
The backup was felt in San Francisco, where city streets were heavily congested heading into the evening commute, especially at freeway entrances, according to a city transit official.
The Van Ness Avenue corridor was moving, but many other key intersections around the city were congested, especially at freeway entrances, said Paul Rose, a spokesman for the San Francisco Municipal Transportation Agency.
"The only thing you can do is be patient at this point," Rose said.
Rose said Muni was not heavily affected by the traffic backup because it has transit-only lanes in the most affected areas.
One driver reported that the Fifth Street and Second Street on-ramps to eastbound Highway 80 in San Francisco were already severely backed up by 4 p.m., with waits of more than 45 minutes.
Many cars gave up and turning around, presumably in search of alternate routes, the driver said.
The California Highway Patrol reported heavy traffic on the Bay Bridge on Friday evening, although other areas so far look relatively normal, a CHP officer said.
With many drivers seeking alternate routes due to the BART strike, however, the congestion is extending to other corridors, said Randy Rentschler, a spokesman for the Metropolitan Transportation Commission.
Traffic Friday was heavy on the Highway 880 corridor and on state highways 24 and 37, among other places, Rentschler noted.
"What's happening now is [U.S. Highway] 101 in Marin is getting backed up because people are taking [Highway] 580, and 580 is backed up,"Rentschler said.
"So even though BART is far away, even though you don't take it, people are coming in from out of town," Rentschler said.