• Project

SR 520 West Approach Bridge North Project

Project overview

The West Approach Bridge North Project extended SR 520’s three westbound lanes, including a transit/HOV lane, from the new floating bridge to Seattle’s Montlake neighborhood. It also expanded the new SR 520 Trail across Lake Washington to Seattle.

Timeline
Construction began in September 2014 and finished in December 2017.
Project status
Completed
Funding
$264 million

What to expect

To make room to construct a parallel eastbound bridge, we've temporarily shifted all traffic over Union Bay. Currently all traffic is on the north bridge, with two lanes and a 40-mph speed limit in both directions. This configuration will last until Montlake Project construction finishes in 2023-2024. At that time, the north bridge will return to a three-lane, westbound-only bridge.

The new eastbound bridge will extend SR 520’s improvements between Montlake Boulevard in Seattle and 108th Avenue Northeast in Bellevue. This includes three lanes in each direction, dedicated HOV/transit lanes and full shoulders. Pedestrians and cyclists can already use the new SR 520 Trail to cross Lake Washington.

Area map of the SR 520 West Approach Bridge North Project