Plan ahead: Seattle's State Route 520 and Montlake Bridge will be closed all weekend

Seattle drivers will want to prepare alternate routes ahead of several major road and bridge closures this weekend.

State Route 520 will be closed in both directions between Montlake Boulevard in Seattle and 92nd Avenue Northeast in Clyde Hill all weekend as crews work to remove an old SR 520 overpass, according to an update from the Washington Department of Transportation (WSDOT). Drivers looking to cross Lake Washington over the weekend should plan to use Interstate 90.

The overpass, which was used as an entrance to the old location of the Museum of History and Industry before it moved to South Lake Union in 2012, was built in the 1960s and has more recently been an off-ramp to Lake Washington Boulevard. The overpass removal is part of the $455 million SR 520 Montlake Project which will create a three-acre lid covering the highway along with seismic upgrades.

The Montlake Bridge, which underwent rehabilitation earlier this year to extend the lifespan of the 97-year-old bridge, will also be closed over the weekend for both vehicle and foot traffic. However, WSDOT is operating a shuttle service for pedestrians and bicyclists using a detour route with the south end pickup/drop-off location on Hamlin Street and the north pickup/drop-off location on Northeast Pacific Street.

Closure times will be slightly staggered according to WSDOT. The following closures will begin starting at 9 p.m. on Friday:

• The Montlake Boulevard on-ramps to eastbound and westbound SR 520.
• The Lake Washington Boulevard on-ramp to eastbound SR 520.
• The SR 520 westbound off-ramps to Lake Washington Boulevard and Montlake Boulevard.

The following closures will begin at 10 p.m. on Friday:

• Eastbound SR 520 between Montlake Boulevard in Seattle to 92nd Avenue Northeast in Clyde Hill.
• Westbound SR 520 between 92nd Avenue Northeast in Clyde Hill and I-5 in Seattle, including the westbound on-ramp at 84th Avenue Northeast.
• The Montlake Bridge and sidewalks between East Shelby Street and Northeast Pacific Street.

Access to both SR 520 and the Montlake Bridge will be restored at 5 a.m. Monday.