Weekend overnight closures of Magnolia Street bridge over 405 set as reconstructed half is readied to open

Crews are working to shift traffic Monday to the reconstructed half of the Magnolia Street bridge over the 405 Freeway in Fountain Valley, requiring overnight closures of the bridge and continuous closure of the southbound freeway ramps at Magnolia through the weekend.

The ramp closures are set for 10 p.m. Friday to 5 a.m. Monday.

Bridge closures are scheduled for:

• 10 p.m. Friday to 6 a.m. Saturday
• 10 p.m. Saturday to 6 a.m. Sunday
• 9 p.m. Sunday to 5 a.m. Monday

The Magnolia Street bridge is being demolished and reconstructed in two stages, one half at a time, allowing it to remain open to traffic during construction. Demolition and rebuilding of the first half began at the end of 2018.

The bridge is being reconstructed to increase the number of traffic lanes from four to six and have bike lanes and sidewalks in both directions.

With the rebuilt half of the bridge prepared to open, the old half is scheduled to be demolished beginning the night of April 4 and require full closures of the northbound and southbound 405, according to the Orange County Transportation Authority. Reconstruction of that section is expected to take about a year.

The bridge is one of 18 that will be replaced, enlarged or built as part of a $1.9-billion project to widen the 405 between the 73 Freeway in Costa Mesa and the 605 Freeway near Rossmoor.

Once that project is completed in 2023, both directions of the freeway on the 16-mile stretch will have an additional general-purpose lane and a new “express” toll lane, according to the OCTA. The existing carpool lane in each direction will be converted to an express lane.

For more information about the project, visit octa.net/405improvement.

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