COWLITZ COUNTY, Wash. — The U.S. Forest Service wants to keep history from repeating itself at Mount St. Helens.
Work is about to begin to reduce the risk of flooding at the largest lake created by the volcano’s 1980 eruption, Spirit Lake.
Historically, lakes surrounding the volcano have flooded some 50 miles to the Columbia River, according to the U.S. Forest Service.
Today, that land downstream is home to the residents of Kelso and Longview.
"There's potentially 50,000 people that could be affected downstream, it’s obviously a major safety issue,” said U.S. Forest Service Project Manager Ryan Cole. “But there's also a huge economic impact potential with the blocking of the shipping channels in the Columbia River."
In the 1980s, the federal government was aware of the flood potential, and a 1.6-mile-long drainage tunnel was built to control the level of Spirit Lake.
Cole said the tunnel receives annual inspections and routine maintenance and is still in good shape, but the federal government is updating the gate system at the lake.
"If any one part of that gate system fails, we've got a backup,” said Cole.
The original gate is going to be replaced by four gates, providing extra support in case a gate fails and more barriers to keep debris and trees out of the tunnel. Trees blown down in the 1980 eruption still float in Spirit Lake.
The work is expected to be completed over the next four summers.
Several hiking trails will be closed during weekdays while the work proceeds at Spirit Lake. The closure order and maps can be found on the U.S. Forest Service website.
According to the U.S. Forest Service, the impacted trails include:
- The southern portion of the Windy Ridge Parking area for contractor staging
- FR 99 extension road from Windy Ridge to the Truman Trail
- TR 207 – Truman Trail from TR 216E – Windy to TR 1 – Boundary
- TR 216D – Plains of Abraham from TR216 – Loowit to FR 99 extension Road
- TR 216E – Windy from TR 207 – Truman to TR 216 Loowit
- TR 207A – Truman from TR 216 – Loowit to TR 207 – Truman
- TR 1E – Harry’s Ridge