Tolt Reservoir and Morning Glory Spillway. From Seattle.gov

Tolt Reservoir and Morning Glory Spillway. From Seattle.gov

Tolt Dam fails another weekly test following windstorm

Seattle Public Utilities will be presenting to the Carnation City Council on Jan. 19.

The Tolt River Dam warning system failed to activate during a regular weekly test for the third time in the last several months, concerning King County Councilmember Kathy Lambert.

In a statement, Lambert called it part of a “pattern of failures” that erodes the public’s trust and confidence in the dam, which is owned by the City of Seattle. The dam’s reservoir provides water to 1.5 million residents in the area.

If the dam were to fail, the city of Carnation could be flooded with more than 30 feet of fast-moving water in a matter of minutes. In addition to the instances of the alarm failing to activate during tests, last July, the system sent out a false alarm, which led to unnecessary evacuations.

“Since that time, the warning system has failed to activate during its routine weekly test on two separate occasions,” Lambert said in a statement. “Over 1,500 residents of Carnation and the surrounding unincorporated areas rely on the warning system to provide accurate and timely alerts in the event of a dam failure.”

In a statement, Seattle Public Utilities, which maintains the dam, said the utility experienced an audio issue on Jan. 13 with its weekly alarm test following the severe windstorm that moved through Puget Sound earlier this week. It resulted in scattered power outages across the region.

“While the alarm did not sound on Wednesday (Jan. 13) during the weekly test, dam safety monitoring was never interrupted. (Seattle Public Utilities) continues to monitor the dam 24/7 using various technology, including cameras and sensors installed along the Tolt Dam,” the statement reads.

Shortly before the test on Jan. 13, staff conducted a weekly internal test and detected a potential issue related to the audio part of the alert test. Partner agencies were notified, including the city of Carnation.

If there were an emergency, the statement reads, an emergency action plan would be activated that includes King County, Carnation and NORCOM to “communicate timely information to the public.”

The statement also addressed the July 28 false alarm, and states that the utility investigated the issue and replaced a control panel. Staff also met with Carnation officials to discuss the incident and plan short-term repairs and long-term upgrades.

“(Seattle Public Utilities) is prioritizing a system upgrade to the Tolt Dam warning system. Staff have begun designing the system upgrade and are expediting implementation for 2022,” the statement reads.

Seattle Pubic Utilities staff will also be making a presentation at the Carnation City Council meeting on Jan. 19.


In consideration of how we voice our opinions in the modern world, we’ve closed comments on our websites. We value the opinions of our readers and we encourage you to keep the conversation going.

Please feel free to share your story tips by emailing editor@valleyrecord.com.

To share your opinion for publication, submit a letter through our website https://www.valleyrecord.com/submit-letter/. Include your name, address and daytime phone number. (We’ll only publish your name and hometown.) We reserve the right to edit letters, but if you keep yours to 300 words or less, we won’t ask you to shorten it.

More in News

file photo
Housing and finance insiders call for subsidized housing families can own, instead of rent

Advocates say increasing homeownership will strengthen the community, build intergenerational wealth

Screenshot taken from Rosa Parks Elementary School website.
Eastside school wins National Blue Ribbon honor

Rosa Parks Elementary School in Redmond is the only Washington school to win.

Matt Laase
Snoqualmie City Councilmember Matt Laase seeks re-election in Pos. 5 seat

Q&A: Laase talks about his priorities and plans if elected.

Photo courtesy of Tanya Lavoy
Tanya Lavoy.
Newcomer Tanya Lavoy seeks Pos. 5 seat on Snoqualmie City Council

Q&A: Lavoy discusses her priorities and plans if elected.

Screenshot taken of a King County video showing Wilburton Trestle
King County’s Eastside to receive major multi-modal transportation investment

Private and public investors will help build a regional biking and walking trail to mitigate traffic

Co-owners Sarah Cassidy and Luke Woodward stand in front of The Grange (photo by Cameron Sheppard)
Co-owners Sarah Cassidy and Luke Woodward stand in front of The Grange (photo by Cameron Sheppard)
How a King County restaurant and farm work together to make a true farm-to-table experience

The Grange prepares sustainably produced meals pulled from the soil of the Snoqualmie Valley.

NW Carpenters Union members strike in front of downtown Bellevue construction site (photo by Cameron Sheppard)
Carpenters union strike interupts some prominent Eastside construction projects

Union representative says members are prepared to strike “as long as it takes.”

Map of proposed landfill expansion sites (screenshot from King County website)
Waste management expert knocks county’s plan to expand landfill

The waste management advocate said the decision to expand seems pre-determined despite assessment.

Most Read