ORANGE – State, federal and local officials gathered today to mark the start of construction on the SR-55 Improvement Project, which is intended to help improve travel times in central Orange County along one of the most heavily congested freeways in Southern California. The $475 million project is funded through a combination of local, state, and federal funds, including $140 million from Senate Bill (SB) 1, the Road Repair and Accountability Act of 2017.

Led by the Orange County Transportation Authority in partnership with Caltrans, the project will add one regular lane and one carpool lane in each direction of SR-55 between I-5 near Santa Ana and Tustin and I-405 near Irvine and Costa Mesa. It will also add merge lanes to help drivers more smoothly enter and exit the freeway.

The SR-55 Improvement Project is an essential part of fulfilling the promises made to voters through Measure M, Orange County’s voter-approved, half-cent sales tax for transportation improvements, also known as OC Go.

“I’m excited for work to get underway on this important project that will help ensure people can continue traveling safely and efficiently throughout the region,” said OCTA Chairman Mark A. Murphy, also the Mayor of Orange. “The SR-55 project will not only benefit those who live or work along this 4-mile stretch of freeway, but also anyone who travels between central Orange County and the coast.”
SR-55 is a vital north-south freeway that links central Orange County and beyond to the coastal region. More than 260,000 vehicles use that stretch of SR-55 every day, and that number is expected to grow to nearly 275,000 vehicles by 2040.

The freeway is also an important route for commercial trucking, with an estimated 17,000 daily truck trips. The improvements are designed to save up to 1,500 hours in daily truck travel time, helping to also improve air quality.

“The additional HOV lanes will encourage more people to carpool and rideshare, which may be able to reduce vehicle miles traveled and travel times for commuters,” said Caltrans District 12 Director Ryan Chamberlain. “The SR 55 Improvement Project also represents the investments we’ve made through SB 1 to fix our roads, freeways, and bridges.”

In addition to constructing the new lanes, the project will improve four bridges that span the freeway, construct retaining walls, reconfigure on- and off-ramps, relocate utilities and make improvements to local streets.

“The SR-55 project is one component in OCTA’s overall goal of creating a balanced and sustainable transportation future for Orange County,” said OCTA CEO Darrell E. Johnson. “I appreciate the community’s patience during construction as we work toward providing relief for the hundreds of thousands of drivers who travel through this area each day.”

During construction, all freeway lanes are expected to remain open during the day, but some work will require lanes to be closed overnight. Temporary and intermittent closures are also expected to occur on freeway ramps throughout the project area, as well as on portions of MacArthur Boulevard, Dyer Road and Edinger Avenue under the freeway. To receive closure information via text message, text ‘55FWYProject’ to (877) 587-3065.

The improvements are intended to help increase access to job centers, health care and educational facilities, as well as John Wayne Airport, among other important destinations for the region.
The SR-55 Improvement Project is expected to be completed in 2026. For more information on the project, please visit octa.net/SR55.
SB 1 provides $5 billion in transportation funding annually shared equally between the state and local agencies. Road projects progress through construction phases more quickly based on the availability of SB 1 funds, including projects that are partially funded by SB 1. For more information about other transportation projects funded by SB 1, visit RebuildingCA.ca.gov.

About OCTA: The Orange County Transportation Authority is the county transportation planning commission, responsible for funding and implementing transit and capital projects for a balanced and sustainable transportation system that reflects the diverse travel needs of the county’s 34 cities and 3.2 million residents. With the mission of keeping Orange County moving, this includes freeways and express lanes, bus and rail transit, rideshare, commuter rail and active transportation. To sign up for more OCTA news, visit octa.net/GetConnected.