For years, Interstate 5 has acted as more than just a freeway running through Irvine. For bicyclists and pedestrians, it has also been a barrier, separating portions of the city’s trail network and forcing riders onto busy streets and across freeway ramps.
That changes Tuesday, when Irvine officially opens the new Jeffrey Open Space Trail Bicycle and Pedestrian Bridge, a nearly 1,200-foot span carrying walkers and cyclists over I-5, Walnut Avenue and a Caltrans Park & Ride lot.
The bridge, which the city says is the largest in Irvine, is 15 feet wide and will connect the existing Jeffrey Open Space Trail and Cypress Village Trail north of the freeway with the trail extension to the south. A ribbon-cutting ceremony is scheduled from 9 to 10 a.m. at the bridge entrance near Jeffrey Road and Walnut Avenue.
Beyond the size of the bridge itself, the project closes one of the most significant gaps in a much larger trail system that Irvine officials say eventually links pathways stretching from the Pacific Ocean toward the Santa Ana Mountains and Cleveland National Forest.
The Jeffrey Open Space Trail originally opened as a 3.5-mile trail in 2015. Work on the current extension and bridge began in March 2024 and includes a new segment running between Barranca Parkway and Walnut Avenue. The extension adds about 1.5 miles to the JOST system.
For cyclists, the significance of the project is not necessarily the additional mileage, but what they no longer have to cross.
Before the bridge, longer trips through Irvine could require riders to leave protected trails and contend with surface streets and freeway ramps. Voice of OC reported last year that some cyclists using the area were dealing with cars traveling around 55 mph as well as vehicles entering and exiting I-5.
The trail can already be used for trips between areas such as UC Irvine and Woodbury Town Center, according to Voice of OC, although gaps in the network have made longer trips more difficult. The new bridge creates a Class I bicycle and pedestrian connection, meaning users are separated from automobile traffic.
When Irvine presented the project to the City Council in November 2023, the estimated total cost of the bridge project was $30.6 million. That included a $23.1 million construction contract with Guy F. Atkinson Construction, approximately $2 million in design engineering, $2.5 million in construction engineering and additional money for administration and contingencies.
The project was financed through several sources rather than one city account. The 2023 funding plan included approximately $5.1 million from a federal Bicycle Corridor Improvement Program grant, $10 million from a California grant, $8.7 million from the city’s Systems Development Fund and $3.7 million from Irvine Recovery Fund money, among other sources.
Separately, Irvine received a $14.5 million state budget allocation in 2021 to help complete the Jeffrey Open Space Trail system, including the extension between Barranca Parkway and I-5.
The price of the overall work also continued to grow.
In October 2025, the Irvine City Council approved an additional $4.812 million in M2 Fairshare transportation funds for the project. That included a $3.75 million change order to Guy F. Atkinson for construction of the JOST extension and another $1.062 million for additional construction-management services from T.Y. Lin International.
Adding the later appropriation to the original $30.6 million project budget brings authorized funding associated with the work to more than $35 million, although that does not necessarily mean the final project expenditure will equal that amount. The $3.75 million change order was specifically identified as funding construction of the trail extension, making it important to distinguish the cost of the bridge itself from the broader extension project.
The bridge is also considerably more complex than a typical pedestrian overpass.
City plans describe a 1,190-foot concrete box-girder structure supported by six columns and two abutments. It includes lighting, retaining walls, landscaping, fencing and other architectural elements designed to match the Jeffrey Open Space Trail. The walking surface itself is 15 feet wide, while the overall bridge structure is about 21 feet wide.
The engineering of the bridge has already received recognition. The Orange County branch of the American Society of Civil Engineers named the JOST bridge its 2026 Outstanding Bridge Project, highlighting its seismic design and role as a missing link in the regional trail system.
The opening also comes later than at least one earlier expectation. In April 2025, Voice of OC reported that the project was expected to be completed in March 2026. The bridge will instead open Aug. 11, roughly five months later.
The city’s current announcement does not explain the change in timing.
Despite the completion of the bridge, Irvine’s larger trail vision does not simply end Tuesday. The new crossing removes one of the most difficult barriers in the network, but the JOST is ultimately one piece of a broader collection of interconnected bicycle and pedestrian routes.
Where Interstate 5 once posed a major challenge to cyclists and pedestrians, they will now be able to travel directly over it with the freeway traffic moving beneath them.
