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I-405 Improvement Project construction alert: Week of May 18

Governor Newsom has issued a “stay at home” executive order to help reduce the spread of COVID-19. Construction of public transportation projects is considered an essential service and is exempt from this order. Work will continue on the I-405 Improvement Project as scheduled.

For more information about this project, please contact the 405 Community Outreach Team at [email protected] or 888-400-8994, or visit octa.net/405improvement.

To view and print a detailed list of closures and detours CLICK HERE!

Click to see closures and detours on the interactive map.

COMING SOON! SB I-405 Goldenwest Street On- and Off-ramps to close for approximately one month

The SB I-405 off-ramp to Goldenwest and the SB I-405 loop on-ramp from Goldenwest are set to close 12 midnight Tuesday, May 26. The ramps will be closed for approximately one month, and will be reconstructed as part of the freeway widening.

The ramps are scheduled to reopen Tuesday, June 23.

COMING SOON! SB I-405 on-ramp from Edinger Avenue to close for approximately one month

The SB I-405 on-ramp from Edinger is scheduled to close 10 p.m. Thursday, May 28. The ramp will be closed for approximately one month, and will be reconstructed as part of the freeway widening.

Scheduled to reopen Monday, July 1*

*Daytime closures are set to continue through May 13, 6 a.m. to 4 p.m

UPDATE! Full Northbound (NB) and Southbound (SB) Beach Boulevard closures set to continue for falsework construction

Crews are constructing falsework for the widened freeway over Beach Boulevard.

This work requires full NB and SB ramp, lane and Beach Boulevard closures between Center Avenue and the freeway ramps.

Nightly closures are ongoing, 9:30 p.m. to 6 a.m. for approximately one more week on weeknights.

REMINDER! Southbound (SB) Full Freeway Closure for Bushard Street bridge falsework construction

Crews are constructing falsework for the Bushard bridge over I-405 in Fountain Valley.

This work requires full SB ramp, lane and freeway closures of I-405 between Warner Avenue and Slater Avenue

The closure is set for the night of Thursday, May 21.

COMING SOON! NB I-405 off-ramp to Seal Beach Boulevard to close for approximately one month

The NB I-405 off-ramp to Seal Beach Boulevard is scheduled to close for approximately one month this summer. The ramp will be reconstructed as part of the freeway widening.

The 405 Community Outreach Team will provide detailed schedule, closure and detour information in future alerts.

UPDATE! Slater Avenue Bridge set to close for approximately one day

The Slater Avenue bridge will be completely closed so crews can continue sealing the expansion joints on both sides of the bridge.

The closure is set for the night of Friday, May 22 from 9 p.m to Saturday, May 23 at 5:00 a.m.

REMINDER! NB I-405 off-ramp to South Coast Drive closed for approximately one month

Crews closed the NB I-405 off-ramp to South Coast Drive.

The ramp is scheduled to reopen Saturday, May 30.

REMINDER! NB I-405 loop off-ramp to Westminster Boulevard closed for ONE YEAR

Crews closed the NB I-405 loop off-ramp to Westminster Boulevard. The ramp will be closed for approximately 12 months to allow construction of new walls and ramps at this location in one stage, eliminating multiple traffic shifts and confusion for motorists.

Construction Activities

Magnolia Street

UPDATE! Crews began installing piles for the foundation for the new Magnolia bridge.

  • Set to begin as early as Monday, June 1, 7 a.m. to 4 p.m. for approximately one month

Bolsa Avenue

UPDATE! Crews began installing piles for the foundation for the new Bolsa bridge.

  • Began Thursday, May 14, 7 a.m. to 4 p.m. for approximately one week

The duration of this work may change depending on site conditions. Please be advised that this work may be loud. Dates and times are subject to change due to unforeseen operational factors or inclement weather.

This article was released by the Orange County Transportation Authority.