Nation's Busiest, Infamously Congested Freeway Opens Carpool Lane

More than 350,000 people travel the 10-mile stretch daily

After five years of delays, two Carmageddons, Jamzilla and countless traffic nightmares, 10 miles of the northbound 405 Freeway carpool lane opened Friday, just in time for Memorial Day weekend.

The new lane opening officially closed the last remaining gap on the congested northbound 405 Freeway as part of the $1 billion Sepulveda Pass Improvements Project, taken on by Metro and Caltrans.

“Any event that ends with the word, ‘mageddon,’ is going to get a lot of attention as indeed it did,” said Gregory Nadeu from the Federal Highway Administration. “But, you worked as a community to help people prepare to get through the closures and now they’ll be able to enjoy the benefits of the new carpool lane.”

Over 350,000 people travel the 10 mile stretch daily, making it the busiest urban highway interstate system in the country, surpassing the No. 2 and 3 busiest freeway stretches along the 60 and 5 freeways by tens of thousands. That number was expected to grow by 50 percent in 10 years according to officials from the Federal Highway Administration.

Primary reasons behind the project included, reducing “existing and forecasted traffic congestion” between the 10 and 101 freeways as well as enhancing “traffic operations by adding freeway capacity,” according to a report released May 2007 by the Federal Highway Administration and California Department of Transportation.

Some commuters were skeptical of the improvements generated by the project.

“Building bigger freeways is not going to be the answer to moving people in Southern California, it’s going to be mass transit and (Metro) Gold Line and the Red Line and the Purple Line and that kind of stuff," a commuter told NBC4.

While others were cautiously optimistic and happy construction on the freeway was finally coming to an end.

“I think the construction was not fun to put up with but I’m hoping for the best and hope it will help with traffic from the sea,” another drive said.

A secondary goal to “improve both existing and future mobility and enhance safety throughout the corridor," was also listed in the report.

Data analyzed by Caltrans officials between Oct. 1, 2002 and September 30, 2005 showed a high frequency of rear-end accidents along the infamously congested freeway, which was “indicative of stop-and-go traffic related to traffic congestion.”

Prior to the opening of the northbound carpool lane, high occupancy vehicles could travel in existing HOV lanes on the 405 from the 5 Freeway in Orange County to the 90 Freeway in Culver City, before it ended. The new opening allows high-occupancy vehicles to continue in the carpool lane to just south of the 101 interchange.

In total, the northbound 405 carpool lane now covers 70 miles, making it the longest carpool lane in the nation.

The segment within the Sepulveda Pass Improvement project was originally built during a time of growth in Los Angeles between 1958 and 1963 as an eight-lane highway, four lanes in each direction. Modifications were made over 30 years later to reduce lane widths and add two additional mixed-flow lanes.

The massive undertaking included making repairs and modifications to existing on-and-off ramps, removing and replacing three bridges, widening 13 underpasses and structures and constructing about 18 miles of retaining and sound walls, some of which has yet to be finished.

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