After nearly yearlong closure, rebuilt Slater Avenue bridge in Fountain Valley will open to traffic Thursday

Wahed Ibrahim from OC 405 Partners looks over the freeway construction site while standing on the Slater Avenue bridge in Fountain Valley, which will reopen Thursday night. The bridge has four lanes, sidewalks and bike lanes on both sides.
(Raul Roa / Staff Photographer)

The new Slater Avenue bridge over the 405 Freeway in Fountain Valley will officially reopen Thursday night after a nearly yearlong closure.

It is the first bridge to be reconstructed as part of the ongoing effort to widen a stretch of the freeway. A total of 18 will be built, replaced or reconfigured throughout the course of the project.

The rebuilt span connecting Brookhurst Street to Bushard Street is 78 feet wide, about 15 feet wider than the original, and has larger sidewalks and bicycle paths on both sides. The bridge also meets the latest seismic criteria and was constructed using pavement designed to limit noise for the surrounding neighborhood, according to project officials.

Although traffic will be able to pass through starting Thursday night, more workers will continue adding finishing touches before the bridge is officially complete. Workers are installing access ramps and lighting and a temporary chain-link fence lining the bridge for pedestrian safety will be replaced with permanent material within the next six weeks.

The northbound 405 between Brookhurst and Warner Avenue also will be closed from 11 p.m. to 5 a.m. Wednesday and Thursday, with southbound lane closures following between 11 p.m. Friday and 5 a.m. Saturday, so workers can remove the temporary falsework that supported the bridge during construction.

Elsewhere in Fountain Valley, workers are scheduled to shutter the Bushard Street and Talbert Avenue bridges over the 405 starting Thursday night so those spans can be demolished and rebuilt. Both are expected to be out of commission for about a year.

Those bridges also will be closed from 9 p.m. Wednesday to 6 a.m. Thursday for electrical work.

Out of the 18 bridges that will be built, widened or replaced as part of the overall 405 Freeway widening project, Slater Avenue will be the first to be completed.
(Raul Roa / Staff Photographer)

Orange County Transportation AuthorityProgram Manager Jeff Mills said Wednesday that the Slater Avenue bridge was simpler to take on compared to others — such as those on Goldenwest and Magnolia streets, which will take two stages of work because they require installing utilities. Those bridges will be complete in about two years, he added.

“In this example, this community has been patient with us and continues to be patient,” Mills said, adding that it’s exciting to see the project reflected in the field.

Once rebuilt, Bushard’s bridge will still have four lanes and sidewalks and bike lanes in each direction. The new Talbert bridge will be widened from four lanes to six and feature bike lanes and sidewalks in both directions.

The pillars currently propping those bridges up over the 405, which were built about 50 years ago with outdated technology, need to be removed to make room for the expanded freeway, according to Lawrence Damore, deputy construction manager for OC 405 Partners.

Mills and Damore said they’re “very excited” about the Slater bridge’s completion, but noted that there is still much work to do.

The overall $1.9-billion freeway expansion project will widen 16 miles of the 405 between the 73 Freeway in Costa Mesa and the 605 Freeway near the Los Angeles County line.

Once the project is complete in early 2023, both directions of the freeway in that stretch will have an additional general-purpose lane and a new “express toll” lane. The existing carpool lane in both directions will be converted to an express lane.

Officials believe the project will help speed up travel times along this section of the 405, which sees more than 370,000 vehicles a day and is one of the most heavily traveled stretches of highway in the nation.

To learn more about the project, visit

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