The roaring Highway 520 bridge will become almost silent this weekend when all motor vehicle lanes close for Montlake lid construction.

That’s a change from previous plans by the Washington State Department of Transportation (WSDOT) to close just the eastbound roadway.

Traffic shutdowns will last from 11 p.m. Friday until 5 a.m. Monday, between Montlake Boulevard in Seattle and 92nd Avenue Northeast in Clyde Hill.

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The walk-bike trail across the Lake Washington floating bridge will remain open.

Crane teams both on the highway deck and on surrounding roads above will be placing the last 30 girders of the future landscaped lid, which will include a bus station.


By closing both directions now, WSDOT can avert another partial weekend closure this spring to deliver girders, according to project spokesperson Steve Peer.

In earlier single-direction shutdowns, the girder setting went quicker than expected, he said. Therefore, last weekend crews used the planned westbound closure to get a head start on electrical installations, he said. This weekend, they’ll set the final 15 concrete girders over eastbound lanes and 15 over the westbound lanes.

This weekend, Graham Contracting will set the final 30 girders for the future Montlake lid, in this image from the company’s construction cam.

The toll bridge has carried only half its normal traffic in recent months, because of remote work during the COVID-19 pandemic, along with restrictions on restaurants, entertainment, religious and social gatherings.

Later this year, north-south traffic on Montlake Boulevard East will be shifted onto the lid temporarily, while the existing Montlake overpass is demolished and rebuilt. The Montlake phase of the $4.65 billion, six-lane Highway 520 rebuild will be completed in 2023 or 2024.