OCTA and Caltrans start I-405 Improvement Project


An innovative project aimed at speeding up commutes on the USA’s busiest stretch of highway started last week when officials broke ground on the I-405 Improvement Project, which targets a 16-mile (25.7km) stretch of freeway between Costa Mesa and the Los Angeles County line in California. 

The US$1.9bn highway project, the largest under construction in California, is being led by the Orange County Transportation Authority (OCTA), in partnership with the California Department of Transportation (Caltrans).

The project adds one regular lane in each direction, between Euclid Street and I-605, as promised to voters through Measure M, Orange County’s half-cent sales tax for transportation improvements.

The project also adds a second lane in each direction, which combined with the existing carpool lanes, will create the 405 Express Lanes, modeled on OCTA’s successful 91 Express Lanes, where solo drivers will have the choice to pay a toll to speed up their commute.

Carpools of two or more people can use the 405 Express Lanes for free for the first three and a half years after opening; cars with three or more people can use them for free at all times.

In addition to constructing the new lanes, the project will build, widen or replace more than 18 bridges, and improve freeway access and traffic on local streets. All this work is critical to accommodate expected growth in Orange County and throughout the region, where traffic on I-405 is anticipated to grow 30% by 2040.

Projections show that without these improvements, by 2040 it would take more than two hours to travel along this stretch, but following the work, travel times are estimated to be reduced to about 30 minutes in the regular lanes, and about 15 minutes if a driver opts for the 405 Express Lanes.

The I-405 Improvement Project is being designed and built by OC 405 Partners, a team of firms led by OHL USA Inc. and Astaldi Construction Corporation, and is set to be completed in 2023.

“The project is designed to provide options and reliability for drivers, and enhance local streets for residents, pedestrians and bicyclists, which is creating what is truly the freeway of the future,” said OCTA’s CEO, Darrell Johnson.

“After 15 years of planning to reach this point, I want to thank the residents and cities, as well as all the local, state and federal officials who have had tremendous input into shaping the I-405 improvements.”

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Tom has edited Traffic Technology International (TTi) magazine and its Traffic Technology Today website since May 2014. During his time at the title, he has interviewed some of the top transportation chiefs at public agencies around the world as well as CEOs of leading multinationals and ground-breaking start-ups. Tom's earlier career saw him working on some the UK's leading consumer magazine titles. He has a law degree from the London School of Economics (LSE).