Sept. 7–13, MAX Blue and Red Line service to be replaced by shuttle buses between Sunset Transit Center and Providence Park

One of Oregon’s most impressive transportation accomplishments of the latter 20th century, TriMet’s Robertson Tunnel, will be the site of a series of MAX improvements in September, requiring a seven-day disruption between Southwest Portland and Beaverton, including through the three-mile-long tunnel.

From Sunday, Sept. 7, through Saturday, Sept. 13, the Robertson Tunnel MAX Improvements Project will close a section of the MAX Blue and Red lines between Sunset Transit Center and Providence Park MAX Station. Shuttle buses will replace MAX service, arriving at stops near the closed stations about every five minutes on weekdays and every seven minutes during the weekend. 

The MAX Blue Line will operate on its regular schedule between Hatfield Government Center and Sunset Transit Center west of the tunnel, and between Providence Park and Cleveland Avenue east of it. Likewise, the MAX Red Line will operate on its regular schedule between Hillsboro Airport/Fairgrounds and Sunset Transit Center west of the tunnel, as well as between Providence Park and Portland International Airport east of it. TriMet’s MAX Green, Orange and Yellow lines will continue running as scheduled during the project. 

In some cases, regularly scheduled bus service may offer a faster or more direct option. Riders can begin planning their trips now at trimet.org/planner.

Robertson Tunnel MAX Improvements: What riders need to know

While TriMet has worked to minimize the disruption as much as we can, some trips may take up to 45 minutes longer than usual. We encourage riders traveling to and from Portland International Airport to be aware of the extra travel time and to plan ahead. 

We apologize for the disruption and appreciate your understanding as crews work on a series of reliability projects in and around the Robertson Tunnel. Riders will want to keep an eye out for signs and TriMet personnel, including our On-Street Customer Service staff, directing them to shuttle bus stops. 

Here’s what you need to know to get a head start on your planning: 

• MAX Blue and Red lines will be disrupted between Sunset Transit Center and Providence Park from Sunday, Sept. 7, through Saturday, Sept. 13. The disruption will affect riders traveling to Portland International Airport during these dates, as shuttle buses can fill up faster and have less space for luggage than MAX trains.

• Some MAX riders who travel through the tunnel may want to use alternative means of transportation or work from home during the disruption if they can.
  
• Shuttle buses will arrive about every five minutes during weekdays and every seven minutes during the weekend. 

• Bus lines 20-Burnside/Stark and 58-Canyon Rd may experience higher ridership, as they may be used as an alternative to MAX service.

For questions or help planning your trip, contact TriMet’s Customer Support Center at 503-238-RIDE (7433), available Monday through Friday, 7:30 a.m. to 5:30 p.m.

Track-to-wire improvements

The Robertson Tunnel MAX Improvements Project will improve the MAX tracks and overhead wire system, keeping rides reliable and comfortable for years to come.

During the seven-day disruption, crews will complete two major projects. One will replace about a mile of the overhead wire used to power MAX trains, including the installation of a new wire tensioning system just west of the tunnel. We installed the same system on the MAX Blue Line in East Portland in spring 2025. These upgraded systems replace the older weight stacks, used to prevent wires from sagging as they expand in high temperatures. They apply about 3,000 pounds of consistent pressure to keep overhead wires taut in all conditions, improving reliability and reducing maintenance needs.

The second project will replace about 700 feet of track between Washington Park and Goose Hollow. Crews will also replace rail ties and perform deep cleaning inside the tunnel. This work is vital, as it targets a part of the system that’s been in service for nearly 30 years.

Making Transit Better

The Robertson Tunnel, finished in 1998, was a huge engineering achievement, with features that are still unmatched today. Among the most notable, the Robertson Tunnel is home to the deepest transit station in North America, Washington Park MAX Station. It serves several destinations at the surface level – 260 feet above, the equivalent of the length of a football field. Destinations include Washington Park itself, along with the Oregon Zoo, World Forestry Center and Hoyt Arboretum. Two popular gardens are also accessible: the Portland Japanese Garden and the International Rose Test Garden.

The tunnel stretches three miles, seamlessly connecting Portland’s Goose Hollow to the Washington County suburbs of Beaverton and Hillsboro. It’s an example of how TriMet has made transit better over the decades, through improvements that ensure the region’s transit investments continue serving riders for years to come. 

Over the past year, these have included the completion of our extension of the MAX Red Line, A Better Red, in August 2024, and the introduction of our newest MAX trains, the Type 6s, in January 2025. We have also completed rail crossing improvements and installed the upgraded overhead wire tensioning system on the MAX Blue Line in East Portland. This June, we also began a months-long project to renovate the NE 82nd Ave MAX Station platform.

Thank you for your patience as we invest in a smoother, more reliable transit system for the future. To learn more about the Robertson Tunnel MAX Improvements Project and how it may affect your ride, visit trimet.org/improvements.