Octa's transportation blog

The I-405 Improvement Project Is Nearly 40% Complete

With construction nearly 40 percent complete, the $1.9 billion I-405 Improvement Project has reached a significant milestone. Construction on the project began in 2018 and includes adding one regular lane in each direction between Euclid Street and I-605, and a second lane in each direction in the center of the freeway from SR-73 to I-605 that will combine with the existing carpool lanes to form the 405 Express Lanes. In addition, 18 bridges are being built, widened or replaced as part of the project, which will speed up travel times on I-405 between Costa Mesa and the Los Angeles County line.

This 16-mile segment of I-405 is one of the most heavily traveled stretches of highway in the nation, and drivers routinely face severe congestion in both the regular lanes and carpool lanes. The project is critical to accommodate expected employment, population and housing growth throughout the region.

Significantly reduced traffic volumes during the COVID-19 pandemic allowed OCTA and its partners to implement extended overnight and daytime freeway lane closures to mitigate schedule delays.

In addition, the McFadden Avenue and Bushard Street bridges are expected to open to traffic this month, and the Talbert Avenue bridge is expected to open early next year. The Edwards Street overcrossing was also recently demolished and is under construction.

Significant bridge construction also continues at Fairview Road, Magnolia Street, Bolsa Avenue, Goldenwest Street, Westminster Boulevard and Bolsa Chica Road. These bridges are being rebuilt one half at a time so they can remain open to traffic.

The first halves of the new Magnolia Street, Goldenwest Street and Bolsa Chica Road overcrossings opened earlier this year, and the first halves of the new Fairview Road, Bolsa Avenue and Westminster Boulevard overcrossings are anticipated to open in the next six months.

Construction on the project is anticipated to be completed in 2023.

For more information about the I-405 Improvement Project, visit here.

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