Bridges

Here is a list of vehicular bridges in Seattle that open for marine traffic:

To see the current federal regulations around opening the Lake Washington Ship Canal bridges, click here.

Information regarding changes in bridge operations is located on United States Coast Guard Local Notice to Mariners website.

Bridges open on request between 7 AM and 11 PM.

From 11 PM to 7 AM, bridges open by appointment only.  

The average bridge opening, from the time street traffic stops to the time it resumes, lasts about 4 minutes. The Spokane St Swing Bridge openings last about 10 minutes. 

Seattle's Ship Canal Bridges - University, Fremont, and Ballard Bridges - have restrictions in place during the morning and afternoon peak commute to help keep street traffic moving during busy hours. These 3 bridges stay closed to marine traffic on weekdays, from 7-9 AM and from 4-6 PM, except for federal holidays but Indigenous Peoples' Day and for any vessel of 1,000 gross tons or over.  

See the federal regulation for Lake Washington Ship Canal bridges here.

Information on Montlake Bridge openings is available here.

Pictured: South Park Bridge

Request an Opening

Between 7 AM and 11 PM: Vessels should contact the bridge by radio (Marine Channel 13), call (206) 386-4251, or use a whistle signal: one long, one short. 

From 7 AM to Dusk: The US Coast Guard requests pleasure vessel use a whistle signal. 

Between 11 PM and 7 AM: Bridge openings are by appointment only and should be requested no less than 1 hour prior to the opening. 

For openings by appointment for the Ship Canal Bridges, the bridge operator will wait 15 minutes after the appointment time before contacting the vessel on Marine Channel 13. If the bridge operator doesn't receive a response, the operator will leave for the next appointment.  

For state- or county-owned bridges, visit www.kingcounty.gov or www.wsdot.wa.gov.

Our moveable bridges operate with complex mechanical and electrical equipment. Though they are rare, issues with these systems can happen. When an outage occurs, our roadway structures crew and engineers work as fast as possible to restore service to the traveling public. To quicken our response, we maintain a Stand-By Crew during weekday off hours as well as weekends and holidays. This crew consists of a lead supervisor, mechanic, and electrician. 

When our roadway structures crew learns of an issue, they take the following steps to get the bridge up and running: 

1. Deploy staff to inspect and identify the problem.  
2. Analyze the issue and identify corrective action.   
3. Some common mechanical issues are traffic control gates or hydraulic fluid pumps not working properly.   
4. Some common electrical issues are problems with bridge motor controls. These send signals to the control panel in the tower. Or there may be problems with the control panel in the tower, which sends signals to open and close the bridge. 
5. If the issue is a bad sensor reading, the solution may be as simple as rebooting the system. Other times, we may need more time to diagnose the problem or to get hard-to-replace parts that take several days to arrive and install. In every case, we perform an assessment of each bridge’s many, independent operating systems in a systematic process. This ensures the highest safety and reliability for the repair.  
6. If the problem is more severe and leaves the bridge out of order for several hours or more, we consult with our traffic control team. We work with them to determine which detours and what signage are needed for short- or long-term bridge closures to meet the needs of commuters during peak traveling hours. 
7. Once the bridge is working again, we run several tests to verify its operation. The bridge will reopen to the public when we are confident that the bridge is functional and safe. 

Mechanical and electrical systems experience ordinary wear and tear over their service life. We have a strong, proactive maintenance system in place to address these issues and keep our bridges in good working condition.

Experiencing a travel delay related to a moveable bridge or have questions about its status? Follow @SDOTtraffic on Twitter for real-time updates.

Our proactive maintenance approach means we work to prevent issues with our bridges and roadway structures before they happen.

Examples of proactive maintenance include:

• Regular safety inspections 
• Removing old paint and repainting bridges. In addition to providing an aesthetic appeal, paint coating protects bridge metal from corrosion and rust due to salt and moisture in the air. Bridges are repainted every 10 to 20 years.  
• Performing bridge cooling on our moveable bridges. When temperatures reach over 85 degrees three days in a row, we spray our moveable bridges with water to keep them cool. High temperatures can cause bridge steel to expand beyond its operational range, potentially creating problems for a bridge’s opening and closing functions and/or damaging the bridge.    

Check out our blog to learn more in detail how we work to preserve and maintain our bridges to withstand the test of time.

We are actively working on several bridges in the city. Visit the project webpages below to learn more:

Below is a list of completed bridge rehabilitation or replacement projects:   

• SW Andover St Pedestrian and Bicycle Bridge Seismic Retrofit Project (Complete)
• 8th Ave NW Bridge Seismic Improvements Project (Complete)
• W Howe St Bridge Seismic Retrofit (Complete)
• Fairview Ave N Bridge Replacement Project (Complete - Reconstruction)
• Northgate Pedestrian and Bicycle Bridge (Complete - New Bridge)
• S Lander Street Bridge Project (Complete - New Bridge)
• Magnolia Bridge Planning Study (Complete)
• Ballard Bridge Planning Study (Complete)
• Cowen Park Bridge Seismic Retrofit (Complete)