A $716 million project is getting underway to add lanes to the 5 Freeway where it runs through Irvine and Tustin.

The Orange County Transportation Authority, along with Caltrans and local leaders, celebrated breaking ground on the work on Friday, Jan. 23, from a property overlooking the 5 between the 405 and 55 freeways, where it will be improved. More than 275,600 motorists travel the stretch each day.

The project will add a lane in each direction and more space for merging and getting on and off the ramps to local streets. The work will also add bike lanes, rebuild sidewalks and make other improvements to those city streets.

The transportation authority’s CEO, Darrell Johnson, called the project “a targeted investment versus a complete freeway rebuild.”

“That’s going to be safety and operations,” he said. “There is a lane addition, but it is really about making sure that everything is standard there.”

With some bigger freeway projects completed, such as the $2.6 billion widening of the 405 in 2023, Johnson has said several of the agency’s recently started or soon-to-start projects are about standardizing lanes, shoulders and the ramps to improve traffic flow and safety.

“This project will improve traffic operations, provide more reliable commuting times and also improve safety along the I-5 corridor,” Caltrans Director Dina El-Tawansy said, adding that, along with meeting current needs, it will accommodate future growth as well. “The I-5 improvement project will strengthen regional mobility, support economic vitality and enhance the overall quality of life for Orange County commuters.”

The OCTA finished a $687 million reconstruction of part of the 5 freeway in South Orange County last spring. That five-year project between El Toro Road and State Route 73 added new lanes in each direction between Avery and Alicia parkways and a second carpool lane from Alicia Parkway to El Toro Road. A main goal was to address congestion in the “El Toro Y” area, where the 5 and 405 blend.

Funding for this latest project comes from Measure M, the half-cent sales tax collected in Orange County for transportation projects, and state and federal contributions.

“We have some of the most highly traveled freeway segments in the country here in Orange County,” Jamey Federico, OCTA board chair and a Dana Point councilmember, said. “Not all the projects in the measure are monumental, if you will. All of them are designed to improve congestion, bottlenecks, safety, traffic flow.”

The project is expected to take about three years, Johnson said, and drivers will start seeing the “real work” by March or April. Updates on construction can be tracked at octa.net/i-5project.

“These upgrades are about more than easing congestion; they are about improving quality of life and supporting economic vitality across Orange County,” Johnson said. “We appreciate the public’s patience as construction gets underway and look forward to delivering long-term benefits for everyone who relies on this corridor.”