Learn more about the new and improved Main Street Bridge currently under construction in Bellevue

By Victoria Miller

Work is already underway for the new and improved Main Street Bridge in Bellevue and once it’s finished it will better function for all types of users. While work continues, we wanted to share a bit more about travelers can expect once the new bridge opens.

We said goodbye to the old Main Street Bridge across Interstate 405 in downtown Bellevue during the weekend of June 18-19. Over 100 crew members worked to complete the demolition work of  the 260-foot-long bridge in 56 hours between late Friday night and early Monday morning of the weekend closure.

Crews are already at work to rebuild a new, longer bridge to accommodate the widening of I-405 as part of the Renton to Bellevue Project. With work expected to wrap up in late fall.

A new Main Street Bridge for more than just drivers

So, how will the new bridge be different from the old one?

The old bridge, built in the 1960s, had four lanes two lanes of vehicular traffic – two in each direction – with a 4-foot-wide sidewalk on each side and no marked or designated bicycle lanes. That put traffic close to the sidewalks and no longer meets current design standards that stress ease of access and use for all travelers.

The new bridge will still have four lanes, two in each direction – but it will be much more friendly to pedestrian and bicycle traffic. The new Main Street Bridge will include a 5-foot-wide bike lane, an 8-foot-wide sidewalk and curb, a 12-and-a-half-foot-wide multi-use path and a 6-foot-wide landscaping planter that also creates a barrier between sidewalks and active traffic.

Cross section of the new Main Street Bridge lanes, bicycle and pedestrian accommodations.

The aesthetic design of the new bridge will integrate with existing structures throughout the I-405 corridor in downtown Bellevue and incorporates decorative finishes. We worked with the community, Bellevue city officials and stakeholders to add design elements inspired by nature that are also visually sensitive to the surrounding areas. Using simple geometric forms, colors and textures for these structures creates continuity along the corridor and establishes a cohesive identity for the project.

Following a multimodal vision

In line with the I-405 Master Plan, developed in 2002, we are working to implement multimodal improvements to move more people more efficiently through the entire I-405/SR 167 Corridor. Pedestrian and bicycle lane improvements are just one way we are working to fulfill that multimodal vision.

Example of the aesthetic design of the new Main Street bridge.

Other multimodal aspects of the Renton to Bellevue project include:

• Construction of portions of the King County Eastrail, including a 2.5-mile paved section along Lake Washington, which opened in November 2021, and a new crossing over I-405 in downtown Bellevue at the site of the former Wilburton rail bridge.
• A new direct access ramp and inline transit station at the Northeast 44th Street interchange in Renton to help support Sound Transit’s Bus Rapid Transit operations.

Main Street Bridge closure details

As a reminder, the Main Street Bridge will potentially be closed for up to five months while crews construct the new bridge. Signs will direct drivers, pedestrians and bicyclists to nearby detours, but travelers should expect increased congestion in the area.

Northeast Fourth Street will operate as the planned detour route, with signs directing travelers around the closure. In addition, Southeast Eighth Street and Northeast Eighth Street will relieve some of the traffic load from Northeast Fourth Street.

After the five-month-long bridge closure, the newly constructed bridge will partially open with one lane open to traffic in each direction for 60 days. Drivers will be able to use the bridge during these 60 days while crews finish construction of the bridge. Pedestrians and bicyclists will not be able to use the bridge during this time. After the 60-day partial reopening, all lanes and sidewalks on the completed bridge will open to all travelers.

How can I stay informed?

Make sure to stay up to date with the latest traffic and closure information by using our real-time travel map. If you would like to stay up to date on I-405 construction, please subscribe to the King County News listserv and/or the Eastside of Lake Washington Transportation News listserv.

If you have questions about this closure or the larger project in general, you can contact our project office at i405sr167program@wsdot.wa.gov or call the 24/7 construction hotline at 425-818-0161.