Construction Updates

Ensure you have the latest information on construction activities and project milestones delivered directly to your inbox. Use the Stay Informed form to subscribe to our project notifications, which will begin once construction is underway. If you require further assistance, please contact our community outreach team—we are ready to assist you.

Click to download to view and print a detailed list of closures and detours.

Download Closure List

Upcoming Events

Community Meeting Info

OCTA's I-5 Improvement Project Community Outreach Team is hosting two community meetings on Wednesday, April 8 and Saturday, April 11.

These meetings are being held to allow the community to ask questions about the project.

Virtual
Wednesday, April 8
5:30 p.m. – 6:30 p.m.
Register at bit.ly/i-5projectmeeting

In-Person
Saturday, April 11
10:00 a.m. – 11:00 a.m.
Frontier Park 1400 Mitchell Ave., Tustin, CA 92780

Community Meeting Map

Download the Flyer

NB Overhead Sign Removal

Construction activities are expected to remove overhead signage on northbound (NB) I-5. This work requires nightly full closures of NB I-5 between Alton Parkway and SR-133 and the southbound (SB) I-5 carpool (HOV) lane adjacent to the center median. Nightly closures are scheduled as early as 10 p.m. to 5 a.m. Thursday, Aug. 20 and Friday, Aug. 21. NB lane closures start as early as 9 p.m. followed by the full closure at 10 p.m.

This work may be loud. The schedule is subject to change due to inclement weather or unforeseen operational issues.

Peters Canyon Demolition

Nighttime construction activities and closures are coming up for the demolition of the remaining outer portions of I-5 at the Peter Canyon Hiking & Riding Trail. This work requires full closures of westbound (WB) and eastbound (EB) Peters Canyon Trail between Bryan Avenue and Harvard Avenue/Walnut Avenue.

Daytime construction activities are ongoing at the I-5 Peters Canyon Hiking and Riding Trail Bridge for cast-in-drilled-hole (CIDH) work.

Intermittent full closures of the Peters Canyon Hiking and Riding Trail at I-5 may occur through late 2026 for moving equipment in the construction area.

At least one lane in each direction will remain open at all times, unless otherwise noted.

Anticipated Schedule
Demolition: As early as Monday, Aug. 24 through Saturday, Aug. 29, 2026.
CIDH: Ongoing through late 2026.

Anticipated Work Hours
Daytime: As early as 6 a.m. to 4 p.m.
Nighttime: As early as 9 p.m. to 5 a.m.

Construction Closures & Detours

View the latest project closures and detours using the interactive map below.

Bridge Sections

Abutment: Support structure at each end of a bridge.

Bent: Support structure located beneath the middle portion of bridges.

Bridge Foundation Construction Methods

What is Pile Driving?

Pile driving is a commonly used method of constructing structure foundations.

To support the structure, a pre-fabricated steel or concrete beam or "pile" is hammered into the soil until it reaches a hard layer of earth beneath the structure foundation.

Activity is best carried out during the daytime due to:

Significant noise
More vibration

pile driving

Social Media Feed

I5 Improvement Project I405 to SR55

Construction Alert

Weekly Construction Alert

As of Aug. 21, 2026

Construction Alert

Weekly Construction Alert

As of Aug. 14, 2026

Construction Alert

Weekly Construction Alert

As of Aug 7, 2026

Construction Alert

Weekly Construction Alert

As of July 31, 2026

Construction Alert

Weekly Construction Alert

As of July 24, 2026

Construction Alert

Peters Canyon Alert

As of July 20, 2026

Photo Gallery

Crews performing drilled foundation work to support the I-5 bridge construction.

Crews are assembling reinforcing steel cages for bridge foundation construction beneath the I-5 bridge

Aerial photos of project area

I-5/Peters Canyon Hiking & Riding Trail

Jamboree and SR-261 Bridges at I-5

Segment 1

Segment 2

Contact the Community Outreach Team

i5Project405to55@octa.net

(888) 209-5550

I5improvement

I-5 (I-405 to SR-55) Improvement Project