Updated

L.A. drivers heed 'Carmaggedon' warnings

Southern Californians were making the ultimate sacrifice Saturday to avoid the "Carmageddon" feared due to the temporary closing of a major highway— leaving their cars in the garage.
A California Highway Patrol officer walks on an empty stretch of the I-405 freeway in Los Angeles on Saturday during a closure for the partial demolition of a bridge. So far, the unprecedented 53-hour shutdown has not delayed motorists for hours on alternate routes. (Mario Anzuoni/Reuters)

Southern Californians were making the ultimate sacrifice Saturday to avoid the dreaded "Carmageddon" — leaving their cars in the garage.

Unusually light traffic flowed freely through the nation's second-largest city despite fears of epic traffic jams spawned by the 53-hour shutdown of a 16-kilometre stretch of one of the region's most critical freeways.

Authorities closed the segment of Interstate 405 on the western side of the metropolis to allow partial demolition of a bridge, warning motorists to stay off the roads or plan alternate routes.

Officials were optimistic that the public far and wide had received the message, though there was some concern the lack of gridlock would make the public complacent and that drivers would get behind the wheel before the freeway's scheduled reopening early Monday.

"We hope they still listen to what we're saying and not go out and try to drive through this area, because it is going to be congested if people do that," said Mike Miles, a district director of the California Department of Transportation, known as Caltrans.

Demolition on schedule

Mayor Antonio Villaraigosa flew over the city in a helicopter and said it was clear there were far fewer cars on freeways and streets than normal, but he cautioned at a midafternoon news conference that there were hours to go.

"It's been one of the most quiet Saturdays I've seen in forever," said Steven Ramada, who had expected to hear lots of cars honking in front of his Sherman Oaks home but instead only heard news helicopters. "Everyone's calling this Carmageddon weekend, but it feels like 'copter-geddon' over where we live," he said.

Progress on demolition of the half-century-old Mulholland Bridge was on schedule, Villaraigosa said. Powerful machines with long booms hammered away at the south side of the span, which is being removed to allow the interstate to be widened. The plan is to leave the north-side lanes standing until the south side is rebuilt.

"We've made great progress," Villaraigosa told reporters at the city's emergency operations centre.

Gail Standish, 47, pedalled from Beverly Hills with her bicycling club to a 405 overlook a few hundred metres from the closed span.

"Everybody's calling this weekend Carmageddon, but seeing the freeway empty it feels more post-apocalyptic," Standish said.

Dire warnings

Authorities looking at the potential effects of the $1-billion interstate project spent months giving the public dire warnings. The event got its name when Los Angeles County Supervisor Zev Yaroslavsky told an early June press conference that "this doesn't need to be a Carmageddon" if people avoided driving.

The potential for total gridlock is rooted in Los Angeles's geography.

The city is divided by the Santa Monica Mountains, which stretch more than 60 kilometres from near downtown westward through Malibu. The populous San Fernando Valley lies on the north side, and the Los Angeles Basin sprawls to the south.

Local and long-distance freeway traffic through the mountains has to squeeze through Sepulveda Pass on I-405 or about eight kilometres to the east through Cahuenga Pass, which carries U.S. 101 through the heart of Hollywood. In between there is no grid of boulevards, just a few narrow, windy canyon roads.

Skirting the closure to the west of Sepulveda Pass would require even longer canyon routes between U.S. 101 and the Pacific Coast Highway.

Demolition work is expected to be completed by 2 a.m. Monday, followed by cleanup and reopening of the freeway at 6 a.m. Another 53-hour closure will be required in the future to demolish the north side of the span.