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Closure of nation's busiest freeway drives 'Carmageddon II' fears in Los Angeles

Eric Thayer / Reuters file

In this file photo, a portion of the 405 freeway is vacant of cars in Los Angeles, Calif., during a weekend closure dubbed "Carmageddon," on July 16, 2011.

As officials in Los Angeles get ready for another weekend closure of a section of the famously-crowded 405 freeway in late September, they're doing things a little differently this time around.

Los Angeles residents were bombarded with urgent warnings last summer, when a heavily-traveled part of Interstate 405 was closed down for weekend construction. "The 405" is the nation's busiest freeway. Southern Californians largely heeded the recommendations to stay off the 10-mile stretch for the 53-hour closure, and "Carmageddon" never lived up to its name.

Later this month, Los Angeles is bracing for another closure of the 405, between Interstate 10 and U.S. 101, on the weekend of Sept. 29. It's already being dubbed "Carmageddon II," but officials are not depending on scare tactics alone this time, the Los Angeles Times reported.

"We realized that you couldn't do what we did the first time the second time quite the same way," Los Angeles Mayor Antonio Villaraigosa said, according to the Times. "(Researchers) said this time around you can't scare people away from the area, it's better to encourage them to stay home ... That's why we're encouraging you to stay local, shop, eat, walk in your neighborhood."

While  things went relatively smoothly in last summer's closure, the Los Angeles County Metropolitan Transportation Authority worries about complacency and says risk factors are exactly the same this time, spokesman Dave Sotero told NBC News. "Our concern is that the public will think that this will be a cakewalk," he said.

That's why officials are still getting the word out via advertising campaigns and news conferences to encourage "Angelenos" to enjoy a car-free weekend.

If drivers ignore the warnings and still hit the road, a worst-case scenario would result in extreme congestion and multi-hour delays, Sotero said. On a typical weekend, half a million drivers use the 10-mile portion of I-405. The goal, according to Sotero, is to get at least two-thirds of the traffic off roads for the closure.

"Now we did this last year and Angelenos heeded our call to stay out of their cars. In fact they did such a great job that afterward we called it Carmaheaven," Villaraigosa said at a news conference Tuesday, according to the LA Times.

Businesses across the city are offering incentives and discounts for people to stay close to home.

"You don’t have to kill the economy on Carmageddon weekend, but you can explore your neighborhood by foot , or ride a bike or use public transit," Sotero said.

Related from NBCLosAngeles.com: Did Carmageddon make way for a baby boom?

Closures will begin on the evening of Friday, Sept. 28 and the freeway closure is expected to continue until the morning of Monday, Oct. 1.

The closure is part of a $1 billion construction project, where contractors will complete demolition work of the Mulholland Bridge in order to widen the 405 freeway in LA. Sections of northbound 405 will be closed this weekend for 10 hours as crews prepare for the final demolition phase, NBCLosAngeles.com reported.

NBCLosAngeles.com's Jonathan Lloyd and John Cadiz Klemack, as well as The Associated Press, contributed to this story.

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