The unforeseen closure of the Downtown Seattle Transit Tunnel yesterday due to a malfunction with our emergency ventilation system at Pioneer Square Station made for a challenging mobility day for many of our passengers. Service is back to normal today, and the entire Sound Transit team extends a sincere thank you to our riders for their patience navigating the system during this disruption.
The cause of the problem was an electrical supply issue that prevented the fan system from ramping up to the speed required to do its job. Without this system functioning properly, we cannot safely operate trains in the tunnel. We have already started an investigation to better understand the underlying cause of the malfunction and what can be done to reduce the risk of similar outages in the future.
Thanks to the hard work of the Sound Transit, King County Metro (KCM) and Seattle City Light teams, we were finally able to the correct the problem early this morning. I also want to thank the work crews for their diligence in diagnosing and fixing the problem, as well as Sound Transit staff who quickly rallied to support our passengers and the KCM team who quickly set up and operated the Link shuttle.
Sound Transit and our partners will continue to develop new and improved processes to quickly respond to unexpected service disruptions and to quickly provide real time communication and support for our passengers. While there are unavoidable disruptions in any operating system, we are committed to continuous improvement in our response to emerging issues and to support our riders.
Editor's note: This story was initially published on Tuesday, Feb. 14, when there was a possibility of the disruption continuing into the morning commute on Wednesday, Feb. 15.