News Releases

Recent inspection found repairs are needed to avoid catastrophic failure on Mt. St. Helens

(Washington, D.C.) – Senators Patty Murray (D-WA) and Maria Cantwell (D-WA) and Rep. Jaime Herrera Beutler (R-WA) have sent a letter to the U.S. Forest Service, the U.S. Army Corps of Engineers and the U.S. Geological Survey, urging the administration to immediately make necessary repairs to a failing tunnel in Washington state. The 1.6 mile tunnel, constructed following the 1980 Mount St. Helens eruption, provides an outlet for Spirit Lake that prevents flooding.

In the letter, the members expressed their concern, writing, “…we wish to ensure federal agencies are doing everything in their power to prevent a structural failure, including communicating their needs to Congress. Complete failure of this tunnel in the shadow of Mount St. Helens could be catastrophic to Washington state on multiple levels.”

More than 48,000 people live in the region around Mount St. Helens and could be affected in the event the tunnel fails and mudflows occur. Mudflows could also cause significant issues in the Columbia River, a major route for maritime traffic.

The full text of the letter is below.

May 7, 2015

Thomas Tidwell

Chief

U.S. Forest Service

1400 Independence Ave, S.W.

Washington, D.C. 20250

Jo-Ellen Darcy

Assistant Secretary of the Army (Civil Works)

U.S. Army Corps of Engineers

108 Army Pentagon

Washington, D.C. 20310-0108

Suzette Kimball

Director (Acting)

U.S. Geological Survey

12201 Sunrise Valley Drive

Reston, VA 20192

Dear Chief Tidwell, Assistant Secretary Darcy, and Director Kimball:

We write with serious concern regarding the state of the Spirit Lake Tunnel, located on the Gifford Pinchot National Forest in our home state of Washington. We understand that the tunnel is in significant need of renovation and repair and we wish to ensure federal agencies are doing everything in their power to prevent a structural failure, including communicating their needs to Congress. Complete failure of this tunnel in the shadow of Mount St. Helens could be catastrophic to Washington state on multiple levels.

While the tunnel is located on land managed by the U.S. Forest Service (USFS) and is operated and maintained by the USFS, it was constructed by the U.S. Army Corps of Engineers (Army Corps). Using funds provided by the USFS, the Army Corps has provided inspection and repair work on the tunnel throughout its existence, and the U.S. Geological Survey (USGS) has monitored seismic activity in the region at the Cascades Volcano Observatory.

The tunnel was constructed following the 1980 Mount St. Helens eruption, which remains one of the most deadly and economically catastrophic eruptions in United States history. The eruption took dozens of lives, destroyed hundreds of homes, and rendered railways and roads unusable. It also resulted in significant disruption to the local ecology, killing thousands of deer, elk, bear, and millions of fish at a nearby hatchery. The eruption also caused a debris flow that blocked natural outflows for Spirit Lake, located to the north of the mountain. The lake level began to rise, and eventually the 1.6 mile Spirit Lake Tunnel was constructed by the Army Corps in order to provide an outlet for the lake and prevent significant future mudflows. Since construction of the tunnel, the Army Corps has conducted routine inspections of the tunnel to ensure its continued functionality.

Unfortunately, a regularly scheduled inspection of the tunnel conducted in October 2014 revealed movement in the tunnel and a narrowing of the inflow location, resulting in a minor lake elevation increase. A subsequent additional inspection conducted in April 2015 revealed that further narrowing had occurred since the October inspection. This is especially concerning given the need for the lake elevation to remain within a certain range. We understand that without extensive repairs, tunnel collapse could result in substantial, rapid outflows from Spirit Lake, resulting in flooding and mudflows in downstream communities.

We are concerned about the potential harm to area communities in the region, including Castle Rock, Longview, and Kelso, should the Spirit Lake Tunnel fail. Cowlitz County is home to over 100,000 people, over 36,000 of whom live in Longview and almost 12,000 of whom live in Kelso and therefore at risk of massive mudflows should the tunnel fail. In addition to impacts on residents, the 1980 Mount St. Helens eruption caused mudflows that ultimately resulted in 3.9 million cubic yards of material landing in the Columbia River. This debris reduced the Columbia River depth by 25 feet, stranding multiple vessels upriver of the blast zone and limited ocean-going vessels from traveling upstream, resulting in economic impacts. The Army Corps makes significant, regular investments in maintaining the Columbia River at a depth that facilitates trade. A failure of the Spirit Lake Tunnel could potentially result in a debris flow into the Columbia River similar to that of the 1980 Mount St. Helens eruption, again interrupting international trade, which is a significant economic driver in our state.

We understand there are ongoing discussions regarding the potential response to the findings of the October 2014 and April 2015 tunnel inspections. We urge your agencies to come to a conclusion on the best path forward, both for immediate repairs as well as a long-term plan for the stabilization of the lake level, in a timely fashion. We are concerned about the potential for failure and the resultant catastrophic impacts our state could face, and we are committed to working with our colleagues in Congress, and your agencies, on solutions to this pressing need.

Sincerely,

Patty Murray  

United States Senator   

Maria Cantwell

United States Senator

    

Jaime Herrera Beutler

United States Senator Member of Congress