RIVERSIDE, Calif. – The Riverside County Transportation Commission (RCTC) is advancing the I-15 Express Lanes Project Southern Extension with the approval of a contract with SC Constructors. The project is a major investment aimed at reducing congestion and improving travel for Riverside County residents along one of the region’s busiest transportation corridors.

“The I-15 corridor is a heavily traveled route in Riverside County and a critical connection for residents, commuters, and goods movement throughout our region,” said Raymond Gregory, Mayor of Cathedral City and Chair of RCTC. “This project is an important step toward helping people spend less time stuck in traffic.”

As a leading transportation agency in California, RCTC is utilizing a Progressive Design-Build method to accelerate completion of the I-15 Express Lanes Project Southern Extension, making it the first major infrastructure project on the state highway system to use such a method. The approval of the Phase 1 contract includes the preliminary design along with validating the project scope and negotiating the cost for Phase 2. Phase 2 will include final design and construction.

The project will extend the existing I-15 Express Lanes approximately 15.8 miles south by adding two Express Lanes in each direction from Cajalco Road in Corona to State Route 74 (Central Avenue) in Lake Elsinore. The project also includes widening up to 15 bridges, constructing auxiliary lanes, installing electronic toll collection systems, and implementing drainage and noise reduction features along existing right-of-way.

RCTC is moving this project forward to provide real traffic solutions for Riverside County’s growing population. Once completed, the project is expected to improve traffic flow and help Riverside County residents and commuters traveling through the I-15 corridor spend less time in traffic.

Based on available funding, this project – with an estimated cost of $740 million – could begin construction in late 2027 and open to traffic by 2030. The Progressive Design-Build Phase 1 contract was approved during the Commission meeting on May 13, 2026.

For more information about the I-15 Express Lanes Project Southern Extension, please visit: rctc.org/15projectsouth