The reason for the 53-hour closure is to take apart the southern side of the Mulholland Bridge, which stands 80 feet high and nearly 600 feet long. Crews will meticulously chip away at the structure, breaking it apart into pieces that are easier to haul away.
Also, 4 feet of dirt will be spread under the bridge to protect the freeway's surface from any falling debris.
See a live cam shot of the Mulholland Bridge construction site.
Several pieces of heavy equipment were brought in overnight as final preparations are in place for the demolition and the dreaded closure.
"We believe that this will go very very smoothly but it does depend on you," said L.A. Mayor Antonio Villaraigosa at a news conference Friday. "And so we're asking the public once again, reminding them to get out of their car, to not go to the Westside in their car, the south valley, the west valley -- to stay at home, to walk to their shopping center, to go to the restaurant, to shop L.A., to dine L.A., but not to get in their car and add to the traffic."
"If there is an emergency, we will get to you. Traffic will not stop us from getting to you throughout the weekend," said LAPD Deputy Chief Kirk Albanese at Friday's Carmaggedon news conference. "So we're going to work in a unified way. We're going to maintain public safety, do our best to keep traffic moving and to the extent that you can stay out of the area -- please do."
This isn't the first time the city had to deal with major closures. During the 1984 Summer Olympics, disastrous traffic jams were predicted but never materialized. The same thing happened when a portion of the 10 Freeway collapsed and had to be shut down for three months following the 1994 Northridge earthquake. Drivers were able to find their way around it.
Optimistic experts predict the same will happen this weekend.
"One of our interesting mysteries as transportation researchers is that traffic just disappears. Sometimes, we don't know where it goes. In the case of the 10, people chose alternate routes but they also just avoided the area. Again, they just adapted their travel to be able to avoid the worst of what they were thinking would happen," said USC professor Gen Giuliano.
Meantime, public safety is a major concern as the closure of the 405 gets under way.
First responders including police, fire and medical personnel have all been preparing for the shutdown.
The city of Los Angeles will be equipped with 200 extra firefighters to deal with any potential emergencies.
"We've hired up additional resources to pre-stage in the impacted neighborhoods so if there is gridlock, and we cannot get a fire resource or an ambulance in there, we have those resources pre-staged in those communities," said Los Angeles Fire Battalion Chief Chuck Butler.
Also, the Emergency Operation Center at City Hall East will hold longer hours Friday to handle any possible problems.
Local hospitals on the Westside are also gearing up for Carmageddon. One of the big concerns going into this weekend was whether doctors and nurses would be able to get to the hospital. Staff shortage was also a main point of concern.
One way to get around that was to keep the doctors and nurses on premises for the whole weekend, and that's just what Santa Monica UCLA Medical Center is doing by setting up a makeshift motel.
The north wing of the hospital hasn't opened yet, but officials will use 100 rooms on three floors to house employees who would otherwise have to commute.
"We can assure that every single patient that requires a nurse has the required nursing care that they need right here on the Westside and will be at work on time," said Posie Carpenter with the Santa Monica Medical Center.
Caltrans began closing on-and off-ramps of the 405 in both directions between the 10 and 101 freeways starting at 7 p.m. Friday.
The freeway closed at midnight and demolition will take place around the clock, with the stretch expecting to reopen at 5 a.m. Monday
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Beat Carmageddon with ABC7
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