Starting in 2025, significant construction on Interstate 5 (I-5) through downtown Seattle will bring major lane reductions and disruptions to one of the region's most vital transportation corridors. This work is necessary to maintain and improve the highway’s infrastructure, with a focus on safety and longevity.

For nine months each year from 2025 through 2027, one direction of I-5 will be reduced to two lanes as crews work to:

• Replace aging concrete panels.
• Resurface bridge decks on the Ship Canal and Lakeview Viaducts.
• Repair and repave approximately 30 ramps.
• Improve drainage and repair structural components of the Ship Canal Bridge.
• Replace bridge expansion joints.

This effort will include three full weekend closures in 2025 and 2027, with four weekend closures planned in 2026. During these closures, traffic will be fully restricted in one direction while crews set, shift, or remove work zones.

Travelers should anticipate:

• Double-lane reductions: Only two lanes of I-5 will remain open in the work zone.
• Narrowed lanes: Open lanes will be reduced to 10.5 feet.
• Speed reductions: A 50-mph speed limit will be enforced in the work zone.
• Express lane adjustments: Express lanes will support traffic flow in the direction of the work zone to mitigate congestion.

While the construction period will be challenging, resources are available to help travelers navigate the disruptions. Drivers are encouraged to plan ahead and consider alternate routes.

Below is a project timeline:

More Information

To learn more about the project visit here.