It's been going on now for years. The delays, the closures and the limitations of the 405 widening project have already caused a lot of hassles. Now comes the biggest hassle of all, an entire weekend without the most reviled and beloved stretch of freeway on the planet.
For everything you need to know during the 405 closure, visit the Carmageddon Toolkit.
Transportation and elected officials have touted the 405 expansion project as a way to ease traffic congestion by adding a 10 mile carpool lane between the 10 and 101 freeways.
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"If you're going from San Fernando to Orange County," CalTrans' Mike Miles said, "this will save 50 minutes in each direction. That will be a great thing for the traveling public to use the system."
But some transportation analysts dispute that assessment, arguing that the inconvenience of what's being widely referred to as "Carmageddon" won't be worth the trouble in the long run.
"I think it's a dangerous argument to make because it does lead people to expect a certain outcome," Allison Yoh of the UCLA Institute of Transportation Studies said.
Yoh says the project will reduce travel time for carpoolers in the short run, and it may slightly ease congestion for those in other lanes. But studies have shown that over time people will adjust their behavior and eventually the 405 will be just as crowded as ever.
“As people realize the added lanes and added capacity means time savings for them," notes Yoh, "those folks who used to use different routes, or who might have used transit or travel during different times of the day are more likely to return to the 405 once the congestion levels have dropped.”
Yoh says a better long term solution would be to add toll lanes and increase parking and vehicle fees, along with higher gas taxes. That way, people would be discouraged from driving. They'd also would be pushed toward public transportation. But those alternatives can be politically difficult to sell to car-loving Angelenos.
“It’s very hard in a region like Southern California where there is so much dependency on the use of automobiles to then say, 'something you’ve traditionally used for free - or relatively low cost - is now gong to cost you something.'”
Caltrans says there may be something to Yoh's argument, but easing congestion isn’t the only reason for the project. It's also supposed to make the freeway safer by widening lanes, improving on and off ramps and bridges, and improving sound walls for those who live nearby.