LOS ANGELES — The event that many feared would be the "Carmageddon" of epic traffic jams cruised calmly toward a finish Sunday, with officials saying a closed stretch of one of the nation's busiest freeways likely would reopen a day early.
The traffic many thought would be a nightmare was much lighter than normal as Los Angeles entered the second day in the shutdown of a 10-mile section of Interstate 405.
Work was so far ahead of schedule Sunday morning that officials were planning to reopen the freeway later in the day.
Authorities closed the segment of 405 on the western side of Los Angeles at midnight Friday for 53 hours to allow partial demolition of a bridge.
For weeks, authorities warned people that driving as usual this weekend could trigger what's been hyped as "Carmageddon" — an event could back up vehicles from the 405 to surface streets and other freeways, causing a domino effect that could paralyze much of Los Angeles.
But the fears of epic traffic jams dissipated with fewer cars on the roads.
"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.
Crews began cleanup efforts Sunday after finishing their demolition work at about 7 a.m., toppling two massive pillars hours ahead of schedule.
The California Department of Transportation was considering reopening the freeway in phases beginning at 11 a.m.
The 405 could be fully reopened as early as 3 p.m., according to Metropolitan Transportation Authority spokesman Dave Sotero.
Demolition work previously was expected to be completed by 2 a.m. Monday, followed by cleanup and reopening of the freeway at 5 a.m., with on-ramps and connectors all reopened by an hour later.
Project contractor Kiewit Infrastructure West faced a $6,000 fine in each direction for every 10 minutes of delay in getting the freeway reopened, according to the city's Metropolitan Transportation Authority. That's a total of $72,000 an hour.
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 news conference Saturday that there were hours to go.
Villaraigosa said workers have made "great progress" on demolition of the half-century-old Mulholland Bridge. Powerful machines with long booms hammered away at the south side of the span, which is being removed to allow construction of an additional freeway lane. The plan is to leave the north-side lanes standing until the south side is rebuilt. Another closure will be required in the future to demolish the north side.
The project picked up its apocalyptic name when Los Angeles County Supervisor Zev Yaroslavsky said at an early June new conference that "this doesn't need to be a Carmageddon" if people avoided driving.
The potential for Carmageddon was rooted in Los Angeles' geography. The city is divided by the Santa Monica Mountains, which stretch more than 40 miles 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 five miles 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.
The 405's load is increased by a major interstate interchange below the south end of Sepulveda Pass and traffic associated with the University of California, Los Angeles, and Los Angeles International Airport.
At the north end of the pass, the 405 connects with a major artery between Los Angeles and San Francisco. Farther north, the 405 also connects with California's backbone highway, Interstate 5.
The drumbeat of warnings about the weekend triggered an instant industry of businesses trying to capitalize. JetBlue offered special flights from Burbank in the San Fernando Valley to Long Beach, with seats for the short hop costing just $4 or $5.
A cycling group saw that as an opportunity for a race. The cyclists started their ride 90 minutes before the flight's departure time to simulate the time that passengers would have to arrive at Burbank. Another member of the group took the flight and all were to meet at a Long Beach park.
Cyclist Stephan Andranian said it took the bikers one hour and 34 minutes to complete the ride from Burbank to Long Beach, largely following the Los Angeles River. Flight passenger Joe Anthony's total travel time including cab ride from Long Beach Airport to the park was just over 2 1/2 hours.
"We want to show that using a bike in LA is not only possible but that it can be faster than other modes of transportation," Andranian said.
Some trespassers have crept on the 405.
Officials report a bicyclist made it onto the road before getting escorted off by police, a man was cited for driving on the roadway, several people were found putting up a large sign, and a man was caught scaling a perimeter fence.
Many mocked the frenzied language surrounding the closure, especially on Twitter, where Hollywood's comedians had at their hometown.
"How's everyone coping with this terrifying apocalyptic nightmare of having to ... oh my god ... stay home with your family?!!!" Bill Maher wrote.
Albert Brooks took was more philosophical in his Tweet: "If we would close the freeways every weekend we would have a great society."