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I-405 Improvement Project Updates

I-405 Interstate Improvement Project Updates

OCTA in cooperation with Caltrans is widening the San Diego Freeway (I-405) between SR-73 and I-605.The project will improve 16 miles of I-405 between the SR-73 freeway in Costa Mesa and I-605 near the L.A. County line. The project includes adding one regular lane in each direction between Euclid Street and I-605 and making improvements to freeway entrances, exits and bridges. In addition, the project will add the 405 Express Lanes, incorporating the existing carpool lanes and a new lane in each direction between SR-73 and I-605.

Currently, the San Diego Freeway (I-405) is one of the most congested freeways in Orange County, carrying more than 300,000 vehicle trips in some sections each day. By 2040,traffic volumes on the I-405 are expected to increase significantly. This project will increase freeway capacity, improve traffic and interchange operations, and enhance road safety to meet state and federal standards.

The new express lanes – incorporating the existing carpool lanes and connectors that opened in 2014 – will give solo drivers the choice to speed up their commute for a toll, and carpoolers may ride in the lanes for free.

The Design-Build contract was awarded to OC 405 Partners, on Nov. 14, 2016 and they are currently developing a project schedule. Construction activities have begun and include restriping portions of the freeway and setting up concrete barrier on the outside of the freeway to protect work areas for activities such as tree removals and grading. Weather permitting, more significant construction activities, such as the first paving operations and bridge demolition activities, are anticipated to commence later this year. The project is anticipated to be complete in 2023.

To view current activities and closures you may go to their interactive map –

SABP Print Solutions is proud to be a part of this important project as a DBE Certified Printing Company.