SAN FRANCISCO — A gasoline tanker truck crashed and exploded into a tower of flames early Sunday, causing a 170-foot stretch of a major Bay Area freeway interchange to warp and collapse on the freeway below, authorities said.
The accident forced the closure of two damaged sections of the heavily traveled maze east of the Bay Bridge, which carries 270,000 vehicles to and from San Francisco each day. Repairs are expected to disrupt traffic for weeks and, some say, months.
"It won't be a matter of days," said California Department of Transportation spokesman Bob Haus. "It will be significant."
No one was killed although the driver of the truck suffered moderate burns.
As demolition of the damaged sections began late Sunday, Gov. Arnold Schwarzenegger issued an emergency declaration to help expedite repairs by streamlining contracting procedures and providing swift funding.
"Undoubtedly," he said, "today's incident will cause severe difficulties for Bay Area commuters."
The incident at the interchange, known locally as the MacArthur Maze, once again demonstrated the vulnerability of California's crowded freeway systems to serious disruption, whether from accidents or natural disasters such as the 1994 Northridge earthquake and the 1989 Loma Prieta earthquake.
Sunday's collapse is expected not only to snarl commuter traffic but also the flow of trucks to the busy Port of Oakland, one of the nation's largest ports along with Los Angeles and Long Beach.
The mayors of San Francisco and Oakland expressed fear that rebuilding could take months -- and they braced for severe vehicle congestion Monday and for the coming weeks.
"This will be one of the most problematic commutes in recent memory," San Francisco Mayor Gavin Newsom told reporters at the California Democratic Party convention in San Diego.
After the truck with a trailer carrying 8,600 gallons of gasoline overturned, the fuel ignited and witnesses reported seeing flames shoot more than 200 feet in the air, the California Highway Patrol said.
Jennifer L. Summers, 36, a free-lance costume designer, was heading east off the Bay Bridge to her home in the Oakland hills when she spotted thick, black smoke ahead. When she pulled off the road, she saw flames rising from the ground.
"There were explosions happening. And there were huge orange, red and yellow flames," she said. "You could see that it was actually burning the freeway."
Meanwhile, Summers saw people driving through the smoke and flames and heard a "creaking sound" as the section of freeway fell.
Although the collapsed section of freeway was left with charred concrete and twisted metal, the CHP said the only reported injury was to the tanker's driver, who despite his burns flagged down a taxi for a ride to a hospital.
The CHP said the initial investigation revealed that driver James Mosqueda, 51, of Woodland, was traveling at an unsafe speed when his tanker hit a guardrail.
A spokeswoman at St. Francis Memorial Hospital in San Francisco, where Mosqueda was transferred after several hours of treatment at a Kaiser Foundation Hospital in Oakland, said he requested that information on his condition not be released.
The accident occurred about 3:45 a.m. on a roadway that normally thunders with commuters.
"We are fortunate that the incident took place at a time of the morning where there were not a lot of people on the freeway," said Oakland Mayor Ron Dellums, adding that many people could have been injured or killed if the freeway had been packed with vehicles.
The accident happened near the scenes of two of the Bay Area's best-known disasters.
In 1982, seven people were killed in the Caldecott Tunnel after a stalled car, a bus and a gasoline tanker were involved in a fiery crash.
During the 1989 Loma Prieta earthquake, 42 motorists were killed when a stretch of Oakland freeway collapsed, and another died when a portion of the Bay Bridge buckled.
Caltrans Director Will Kempton declined to estimate how long it would take to repair Sunday's freeway damage.
But he said that repairs to the Bay Bridge after Loma Prieta -- which took about 30 days, although the eastern span is now being replaced -- were simpler because they involved elevating a section of deck.
Fixing the East Bay interchanges, Kempton said, will be more like the work that was needed to repair buckled portions of Interstate 10 after the Northridge earthquake. That job took 55 days, but Kempton said the job of fixing I-580 and I-880 in Oakland is somewhat smaller.
"We're going to move with as much speed as we can because we can recognize the significant traffic impacts," he said.
