Scientific committee members will hold a public meeting in Kelso on Jan. 25 to discuss their recent study on long-term management plans for Spirit Lake.
The National Academies of Sciences, Engineering, and Medicines prepared the report to examine downstream effects from Mount St. Helens’ 1980 eruption, according to a press release.
The study suggests that a backup means should be explored to prevent Spirit Lake from breaching a natural debris dam that blocked its old outlet into the north fork of the Toutle River. For now, a 1.5-mile drainage tunnel cut through Harrys Ridge drains the lake and prevents it from rising to a dangerous level. But the tunnel conduit has required more than $7 million in maintenance since it went into service in 1985, and the tunnel crosses several faults.
Should the blockage fail, it would cause catastrophic flooding along the Toutle, Cowlitz and Columbia rivers, according to previous studies.
“This study serves as a foundation to work with communities, and with agencies responsible for managing watersheds impacted by the 1980 eruption,” Gina Owens, Forest Supervisor for the Gifford Pinchot National Forest, said in the press release. “Addressing and mitigating impacts from the 1980 eruption necessitates a cooperative effort amongst federal, state and local agencies.”
The committee held three public sessions in the Kelso/Longview area during 2016 to hear from the local community.
The full report is posted on the National Academies of Sciences, Engineering, and Medicines’ website www.nap.edu.
The National Academies’ meeting on Jan. 25 will start at 2 p.m. at the Red Lion Hotel, Kelso.