Federal officials said a tunnel used to regulate the water level in Spirit Lake at the base of Mount St. Helens needs to be repaired to reduce the danger of flooding.
Cowlitz County officials are concerned that if the tunnel failed, Spirit Lake could fill up and possibly flood downstream towns Kelso and Longview.
“If that tunnel were to fail right now, concern would grow over the next several months," Cowlitz County Sheriff Mark Nelson said in a statement. "If it were to fail during a heavy winter rain event, it could be catastrophic to every community downstream on the Toutle and Cowlitz rivers.”
The 1.6 mile-long tunnel runs between the Spirit Lake and Coldwater Creek. It was installed after the May 1980 eruption of Mount St. Helens.
Janine Clayton, the supervisor of the Gifford Pinchot National Forest in Southwest Washington, said the tunnel is still functional.
“There’s a zone a little past halfway in the tunnel that’s a fault zone, a sheer zone, (and) there’s a little bit of movement. Generally the terrain up here is not that stable. It’s volcanic," she said Wednesday. "What was originally a big culvert – the tunnel – is getting compressed so it’s losing a little bit of its integrity. There’s some work that needs to be done to shore that up.”
Clayton said the U.S. Army Corp of Engineers is expected to complete the project later this year.
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