LOS ANGELES >> For those who say the weekend-long freeway closure dubbed "Carmageddon" was a non-event, Los Angeles County’s transit agency has two words: You’re welcome.

Los Angeles County Metropolitan Transportation Authority spokesman Dave Sotero said the agency’s coordination of wide-ranging efforts to keep residents out of their cars — especially in the area around the shut-down portion of Interstate 405 — kept the weekend of freeway construction from generating the epic traffic jams that many had feared.

"People thought we were crazy. They said there’s no way to get two-thirds of the motorists who drive the 405 to stay away or stay home here in Los Angeles, the car capital of the world," he said. "But we actually did it."

On Monday afternoon, about 24 hours after the 10-mile freeway stretch linking the San Fernando Valley and the Los Angeles Westside reopened almost a day ahead of schedule, traffic on area roads was back to its normal congested but functional state.

"It’s just a typical day," said California Department of Transportation spokeswoman Judy Gish.

Crews finished demolition work on the bridge early Sunday, toppling two massive pillars and creating about 4,000 tons of rubble to be removed.

Project contractor Kiewit Infrastructure West could have been fined $72,000 an hour for a delay in getting the freeway reopened, the MTA said.

Instead, Kiewit will receive an extra $300,000 for finishing early. The early finish saved $400,000 — even with the Kiewit bonus — since paying workers for an additional 12-hour shift would have cost $700,000.

Sotero said the contractor had accounted for possible mishaps — such as worker injuries, equipment problems and damage to the surrounding roads — when it estimated work would take 53 hours, but none of those fears came true.

Mayor Antonio Villaraigosa praised Kiewit for working so quickly and thanked city residents for heeding calls to stay off the roads. He also gave credit to news outlets for spreading word about the closure.

"This weekend was more of a ‘Carmaheaven’ than a Carmageddon," Villaraigosa said in a statement.

Sotero attributed the smooth weekend to cooperation among law enforcement agencies, city governments, transit authorities and others, who all pitched in to spread the word about the impending shutdown of one of the nation’s busiest freeways.

For weeks, officials have issued grim warnings about the closure in the same tones reserved for floods and threatening wildfires.

To prepare the public for the closure, they flashed signs on freeways as far away as San Francisco reminding drivers over and over: Stay off the 405 July 16-17.

Los Angeles Police Department officials recruited celebrities with large followings on Twitter, such as Ashton Kutcher and Kim Kardashian, to get out the message.

Facebook agreed to direct some 6.6 million driving-age people in the greater Los Angeles area to the MTA’s Facebook page detailing the latest traffic conditions this weekend.

As a result, traffic on many area freeways appeared to be lighter than on a typical weekend.

Some residents seemed to interpret the easy driving as evidence that the warnings were overblown and seethed at what they saw as needlessly canceled driving plans and other adjustments to their weekend schedules.

Westside resident David Noll complained during the weekend that he heeded the warnings and told his parents to cancel plans to come from the San Francisco Bay area for a visit.

"They made us believe that this weekend was going to be the worst thing ever, so I told my parents to stay home," he said. "I’m upset because we could have been hanging out together right now."

But University of Delaware sociology professor Joanne Nigg, a disaster-readiness expert who watched the "Carmageddon" saga unfold form across the country, said the weekend went off smoothly because of the warnings and other preparations.

"If they hadn’t had this sort of education campaign ahead of time, if people hadn’t taken alternate roads or changed their plans, it could have been horrible," she said. "In retrospect, people might say it wasn’t a big deal but it could have been."

Nigg said authorities in Los Angeles are especially adept at spreading such warnings because of their experience managing responses to earthquakes and other emergencies. Southern California’s vulnerability to quakes, wildfires and other calamities has also made area residents quick to adapt to adversity, she said.

Throughout the demolition job, powerful machines with long booms hammered away at the south side of the half-century-old Mulholland Bridge, which was 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 about 11 months to demolish the rest.

Officials said they were hopeful that the future shutdown would run just as smoothly as this one, but questions loomed over whether commuters would again heed dire warnings about massive traffic after the weekend went so smoothly.

"What we’re afraid of is that the public will think this is a cakewalk for the next time we do this," Sotero said.