Highway 520 to close all weekend

All of Highway 520 across Lake Washington will close this weekend to drivers and cyclists as Washington State Department of Transportation crews install girders across the road for a new bike and pedestrian bridge.

The closure, starting 11 p.m. Friday to 5 a.m. Monday, will include the span between the Interstate 5 ramp in Seattle to 92nd Avenue Northeast in Clyde Hill.

This weekend’s work is one piece of the $455 million Highway 520 Montlake Project, and will build part of the foundation for a new path for cyclists and walkers to avoid the chaos of Montlake Boulevard. Crews will install 30 girders over the highway to support the new bridge, which will hook into the existing trail across the lake.

Workers also will install seven girders to support an HOV ramp leading to and from a new pedestrian and cyclist deck bridge over the highway.

Contractors are closing in on the final stretch of the long-planned overhaul of the busy and often hectic stretch just south of the Montlake bridge. With much of the girding and supports falling into place, WSDOT says construction of the Montlake Project, with the new deck bridge as a centerpiece, should be completed in 2024.

Money for the project has come mostly from the state, with a recent new infusion of cash from the Legislature’s $17 billion Move Ahead Washington funding package, passed in 2022. A conservative advocacy group recently sued the state, seeking a repeal of the package, arguing it violated rules related to having multiple subjects in one bill. Democrats who passed the legislation expressed confidence the lawsuit would fail.