The Salmon Bay Rail
Bridge Project

The Rehabilitation Project

Since the early 1900s, the BNSF Salmon Bay Rail Bridge has enabled freight and passenger trains to cross the Lake Washington Ship Canal in Seattle. When raised, the bridge also allows commercial and recreational maritime traffic to transit the canal between Lake Union and Puget Sound.

Over the years, BNSF has invested millions of dollars extending the operational life of the century-old bridge, but frequent openings have taken a toll. Diagnostics indicate that the system that allows the bridge to open and close is starting to fail.

Based on expert analysis and review, BNSF has developed an innovative rehabilitation strategy for this critical system. The approach preserves the historical design of the bridge; minimizes operational, in-water, environmental, and community impacts; and continues the bridge’s public and private industry benefits.

Salmon Bay Bridge

Connecting Rail and Maritime To Critical Industries and Destinations

The BNSF Salmon Bay Rail Bridge efficiently moves people, goods, and boats directly to their destinations. On average 30 to 40 trains cross the bridge per day, including Sounder and Amtrak passenger trains. Trains carry shipments to and from the major ports of Seattle and Tacoma and to customers around Washington State. Annually, 50,000 commercial and recreational maritime vessels travel under the bridge.

Critical to Our Economy and the Planet

The rehabilitation strategy developed by BNSF Railway will keep the Salmon Bay Rail Bridge functional, ensuring an efficient multimodal transportation system. The bridge is essential infrastructure. No alternate rail route exists to serve commuters or regional ports, and marine traffic depends on it to function reliably for passage.


If the Mechanism Failed Today, Consequential Scenarios Would Occur…

Freight and passenger rail traffic will not
be able to use the bridge.

Commercial and recreational vessels will not
be able to go under the bridge.

Rail and maritime impacted. Bridge forced
to up position, per federal law.


A bridge failure would also create complex issues beyond the significant disruption in rail and maritime traffic. People and freight would be forced to use alternate routes and methods of transport, adding further stress to roadways, other rail routes, drivers, businesses, and the environment.

The energy and impact offsets of the bridge project will save hundreds of millions of road and train miles and millions of gallons of fossil fuels. Both public and private sectors benefit from the continued reliable operation of the bridge, with more than $650 million in estimated avoided costs over a 25-year period.

History of the Bridge

  • Great Northern Railroad authorized construction of the jackknife-style bridge in 1912.
  • The bridge spans Salmon Bay and connects the Magnolia/Interbay and Ballard neighborhoods in Seattle, Washington.
  • For over 100 years, the bridge has been an essential component of commercial and recreational traffic in the Pacific Northwest with approximately 30 to 40 trains—including Amtrak and Sounder passenger trains—crossing the bridge each day.

Since bridge completion, frequent maintenance and upgrades have ensured its safe and efficient use.

Major updates include:

  • 1948 – Counterweight rebuilt
  • 1980 – Main operating strut replaced
  • 1995 – Main drive machinery and motors replaced
  • 2010 – Counterweight trunnion bearings replaced
  • 2013 – Most recent replacement of movable joints
  • Timber tie deck replaced multiple times over the years
  • Common steel maintenance such as replacing stringers and repairing corroded members has occurred throughout the life of the bridge
  • Operator house has been continuously updated and maintained

Built between 1912-1915, BNSF has invested millions of dollars to maintain and upgrade the bridge to extend its operational life.

Project Updates

December 2023

  • Final planning and initial site preparation for repair work, estimated to occur later in 2024 during work windows set to minimize impacts to marine life, biodiversity and commerce.
BNSF rails in SODO, Seattle

BNSF’s Commitment to Washington

Washington is home to over 3,700 BNSF employees who share our commitment to protecting the environment while safely and efficiently transporting our region’s products around the world.

In 2020, BNSF invested approximately $3.1 billion in capital across its system. The largest component of the plan replaced and maintained BNSF’s core network and related assets to ensure BNSF continues to operate a safe and reliable network. In addition, the plan invested in expansion and efficiency projects and acquiring new freight cars, locomotives, and other equipment. In 2019, BNSF invested approximately $170 million in Washington for capital projects.

Employees: 3,728
Combined Payroll: $313,016,656
Route Miles: 1,335

Get in touch.

Contact us for questions on the BNSF Salmon Rail Bridge Rehabilitation project.