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I-405 Improvement Project construction alert: Week of Aug. 17

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.

NEW! Fairview Road Bridge Girder Placement

Crews are scheduled to install precast concrete girders for the new Fairview Road bridge over I-405 in Costa Mesa.

This work will require full freeway, ramp and lane closures.

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

UPDATE! Southbound I-405 Loop Off-Ramp to Westminster Boulevard to Closure is POSTPONED

The SB I-405 loop off-ramp to Westminster is POSTPONED.

The 405 Community Outreach Team will provide an update when the closure is rescheduled.

REMINDER! Northbound I-405 Loop Off-Ramp to Bolsa Avenue to Close For 24 hours

Crews will close the NB I-405 loop off-ramp to Bolsa to conduct paving operations and reconstruct the ramp. During this time, Bolsa will also be reduced to one lane in each direction between Goldenwest Street and Chestnut Street.

The ramp detour is:

  • NB I-405 off-ramp to Beach Boulevard → Beach → Bolsa

The 24-hour closure is set for 10 p.m. Friday, Aug. 21, to 10 p.m. Saturday, Aug. 22.

REMINDER! Southbound I-405 Loop Off-Ramp to Beach Boulevard is PERMANENTLY CLOSED

The SB I-405 loop off-ramp to NB Beach Boulevard is permanently closed. Motorists will use the Beach Boulevard/Center Avenue off-ramp from now on to access NB and SB Beach Boulevard.

The loop off-ramp was eliminated to accommodate the widening of Beach Boulevard and of the freeway. The Beach Boulevard/Center Avenue off-ramp and Center Avenue are being reconstructed to accommodate the change in traffic volume.

UPDATE! Southbound (SB) Full Freeway Closures for Bolsa Avenue Bridge Falsework Installation

Crews are constructing the falsework for the Bolsa bridge over I-405. This work requires full SB freeway closures between Goldenwest Street and Bolsa.

The closures are set for 11 p.m. to 5 a.m. Wednesday, Aug. 19, to Tuesday, Aug. 25, on weeknights.

NEW! Northbound (NB) Full Freeway Closures for Bolsa Avenue Bridge Work

Crews will continue working on the Bolsa bridge. This work requires full NB freeway closures between Beach Boulevard and McFadden Avenue.

The closures are set for:

  • 10 p.m., Monday, Aug. 24, to 6 a.m. Tuesday, Aug. 25; and
  • 11 p.m., Wednesday, Aug. 26, to 5 a.m., Tuesday, Sept. 1, on weeknights

REMINDER! Northbound (NB) and Southbound (SB) Euclid Street Intermittent Closures Are Set to Continue

Northbound and southbound Euclid lane reductions and directional closures will continue 9 a.m. to 3 p.m. and 10 p.m. to 5 a.m. through Friday, Aug. 21.

REMINDER! Full Northbound (NB) and Southbound (SB) Beach Boulevard Closures for Pavement Operations and Falsework Removal

Crews will continue paving and falsework removal activities on Beach Boulevard. This activity requires NB and SB Beach Boulevard closures.

The closures are set to continue 11 p.m. to 5 a.m. through Friday, Aug. 21.

UPDATE! Northbound Beach Boulevard Freeway Ramps are NOW OPEN

The northbound (NB) loop on-ramp to NB I-405 and the NB I-405 off-ramp to NB Beach are now open to traffic.

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.

REMINDER! NB I-405 Loop On-Ramp from Goldenwest Street is Closed for Approximately THREE MONTHS

The NB I-405 loop on-ramp from Goldenwest Street is closed for approximately three months. The ramp is being reconstructed as part of the freeway widening.

The ramp is scheduled to reopen Oct. 2.

Construction Activities

Fairview Road

NEW! Crews will install piles for the foundation of a wall adjacent to the northbound I-405 on-ramp from Fairview.

  • Pile driving is set for 7 a.m. to 4 p.m. for approximately one month on weekdays.

Santa Ana River

NEW! Crews will install piles for the foundation of the walls along northbound I-405 between Harbor Boulevard/Hyland Avenue and the Santa Ana River, and along southbound I-405 adjacent to Moon Park.

  • Pile driving is set to begin as early as Friday, Aug. 21, 7 a.m. to 4 p.m. for approximately three weeks on weekdays.

East Garden Grove Channel

UPDATE! Crews are continuing construction on the East Garden Grove Channel near the Newland Avenue bridge.
Activities include installing shoring by vibrating in steel beams, excavation, demolishing concrete and hauling materials.
Crews will also begin pile driving for the widened I-405 bridge over the channel.

  • Ongoing, 7 a.m. to 4 p.m. for approximately one month
  • Crews may mobilize equipment as early as 6 a.m.
  • Some activities, such as hauling materials, may occur at night.

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.