Bellevue commuters who rely on the 2 Line to cross Lake Washington now know what went wrong: the Aug. 1 derailment that shut down their route for 14 hours was caused by two bolts that sheared off a 20-year-old pocket track at Chinatown-International District Station.

The empty train had been repositioning onto the pocket track just before midnight on Aug. 1 to add capacity for crowds leaving an Ed Sheeran concert at Lumen Field. When the two bolts failed, the curved track leading to the pocket became misaligned, sending the train off the rails. Only the operator was aboard. No one was injured.

The derailment shut down the downtown Seattle tunnel, cutting 2 Line service to and from Bellevue until 2:15 p.m. Sunday, Aug. 2. Sound Transit ran shuttle buses between Capitol Hill, SODO and Judkins Park stations during the outage.

Balducci pushes for better rider communication

King County Councilmember Claudia Balducci, who represents the Bellevue area on the Sound Transit Board, raised the derailment at the agency's Rider Experience and Operations Committee on Aug. 6.

"A derailment is a life-threatening situation," Balducci told the committee. "I'm really interested to know that we know what happened so that it's not going to happen with a train with people on it."

Balducci said she received extensive feedback from constituents about wayfinding failures during the outage, specifically riders who could not find the shuttle buses. She called on Sound Transit to upgrade its standards for unplanned disruptions: immediate delay announcements, disclosure of the cause when known and clear directions to shuttles.

Sound Transit CEO Dow Constantine told the committee the agency is "quite rigorous" in processing lessons learned and called the derailment an event where the agency has opportunities to improve the passenger experience.

Investigation details and system-wide inspections

Deputy CEO Ed Cobean told the committee that only one other switch in the entire system resembles the special track work at the CID pocket track. That switch has already been fully inspected and its bolts replaced. Sound Transit is sending the failed bolts out for metallurgy testing to determine why they broke.

The agency has also committed to additional inspections across the system for all other switches, not just the two pocket-track locations.

Context: a rough stretch for reliability

The derailment capped a string of disruptions in July: a roof hatch issue caused a 15-hour outage on July 9, mechanical problems hit trains on July 10 and July 20, and a power outage suspended service between Beacon Hill and Tukwila International Boulevard on July 21.

A separate Aug. 10 incident at Rainier Beach, initially reported on social media as another derailment, turned out to be a split switch. That train moved back out under its own power, and normal 1 Line service resumed about two hours later.

Sound Transit said it temporarily suspended its monthly maintenance program during the World Cup period to maximize capacity but maintained that World Cup wear and tear did not cause any of the recent disruptions. The agency's draft 2027 service plan proposes expanding maintenance windows by shortening service spans at certain times, and public feedback on that proposal is open.