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I-405 Improvement Project construction alert: Week of Sept. 14

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.

REMINDER! Northbound I-405 On-Ramp from Warner Avenue is Closed for Approximately One Month

The NB I-405 on-ramp from Warner is closed for approximately one month. The ramp is being reconstructed as part of the freeway widening project.

REMINDER! Northbound I-405 On-Ramp from Magnolia Street to Close for Approximately One Month

Crews will close and reconstruct the NB I-405 on-ramp from SB Magnolia for approximately one month to accommodate the freeway widening. Activities include demolition, excavation, grading, drainage and electrical system installation, concrete pours and asphalt paving.

The ramp is set to close as early as 10 p.m. Thursday Sept. 17.

NEW! Northbound (NB) and Southbound (SB) Freeway Traffic Breaks

Crews will conduct traffic breaks on I-405 for utility line relocation. The California Highway Patrol (CHP) will stop traffic for up to 10 minutes at a time. This work also will require closure of the SB I-405 on-ramp from Euclid Street/Ellis Avenue.

  • The traffic breaks and ramp closure are scheduled between 4 a.m. and 6 a.m. Sunday, Sept. 20

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

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

Nightly closures are set to continue 11 p.m. to 5 a.m. Wednesday, Sept. 16, to Friday, Sept. 18.

UPDATE! Northbound (NB) Full Freeway Closures for Bolsa Avenue Bridge Falsework Installation

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

Nightly closures are set to begin as early as 11 p.m. to 5 a.m. Monday, Sept. 21, to Saturday, Sept. 26.

NEW! Southbound (SB) Full Freeway Closure for Fairview Road Bridge Concrete Pour

Crews will continue working on the Fairview Bridge over I-405. This work will require SB full freeway, and ramp closures, as well as lane reductions of NB I-405 and ramp closures.

Nightly closures are set to begin as early as 10 p.m. to 5:30 a.m. Monday, Sept. 21, and Tuesday, Sept. 22.

NEW! Northbound (NB) and Southbound (SB) Full Freeway Closures for Talbert Avenue Bridge Falsework Grading

Crews will be grading the falsework for the Talbert bridge over I-405. This work requires full NB and SB freeway closures between Brookhurst Street and Euclid Street.

The 405 Community Outreach Team will provide detailed schedule information in future alerts.

Construction Activities

Santa Ana River

REMINDER! Crews are installing piles for the foundation of the walls along northbound I-405 between Hyland Avenue and the Santa Ana River, and along southbound I-405 adjacent to Moon Park.

  • Ongoing 7 a.m. to 4 p.m. for approximately three weeks on weekdays.

NEW! Crews are scheduled to perform concrete work and relocate a waterline at the Santa Ana River Trail crossing under I-405. This requires closing one direction of the trail at a time during the day to complete the work safely.

  • The trail is set to be reduced to one lane at a time as early as Tuesday, Sept. 22, for approximately one week.

Brookhurst Street

REMINDER! Crews restriped Brookhurst to two lanes in each direction to create a work area in the center median between Slater Avenue and Talbert Avenue.

The center median will be demolished and removed to allow traffic to be shifted prior to the upcoming partial demolition and construction of the first half of the Brookhurst bridge.

This median removal and additional prep work will take approximately 1.5 months.

Median removal and prep work are scheduled for 7 a.m. to 4 p.m. on weekdays for approximately 1.5 months.

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.