Getting there: This year, state workers won’t have to use a Howitzer to control avalanches at Snoqualmie Pass avalanche control

Washington transportation officials will no longer rely on a collection of artillery to shoot loose snow on Snoqualmie Pass to safely trigger controlled avalanches above Interstate 90.

The roadway typically receives upwards of 450 inches of snow a year, which could be dangerous for the 28,000 vehicles that rely on it on a typical day. The most common area for avalanches on the roadway is the west side of the pass.

Thanks to a million-dollar appropriation from the Legislature, the Washington State Department of Transportation recently completed the installation of a remote-controlled avalanche control system on the mountain pass.

According to the agency, Washington joins Colorado, Utah, Alaska, Wyoming and California in adopting the technology. A similar system is also in use on Stevens Pass.

“This is a safer, more effective system than what we were previously using to get the job done,” Tina Werner, a state transportation spokesperson, said Thursday.

The new system will replace methods previously used on the mountain pass for decades. Since the 1980s, transportation crews have used artillery including a recoilless rifle, an M60 tank and a World War II-era Howitzer that was loaned from the United States Army to shoot snow loose in the mountain.

The shots would trigger a controlled avalanche safely above the closed roadway.

The agency has relied on artillery to shoot snow above the roadway, a process the agency says is “outdated” and required crews to work closely to the explosives that trigger the avalanche.

But shooting artillery had downsides.

According to the state, the process could include upwards of six hours of preparation before the first artillery shot was fired. The roadway would also remain closed for hours following the artillery shot as crews cleared the roadway.

WSDOT discontinued the tank in 2018, after the agency said it reached the “end of its useful life.” The U.S. Army has since decommissioned the tank.

“That’s why for several years we’ve been working toward replacing our old, inefficient system that forces controlled avalanches on Snoqualmie Pass with safer, more reliable technology,” Werner said.

The Howitzer is currently the only artillery used for avalanche control in the United States, Werner said.

The new system includes six remote-controlled avalanche control towers and deployment boxes on the mountain pass that are powered by solar panels. The system, which detonates explosives that trigger controlled avalanches above the roadway, was funded through a million-dollar appropriation included in the transportation budget approved by state legislators earlier this year.

According to WSDOT, the new system provides several benefits, including increased safety for crews clearing snow, a longer lifespan for the equipment and reduced set up times.

“Previously, my crew was less than a foot away from launching artillery systems,” John Stimberis, avalanche control supervisor for Snoqualmie Pass, said in a statement. “Now we’ll be able to force an avalanche in a controlled environment, potentially miles away.”

The avalanche system can be set up in minutes and could reduce road closures to between a half hour and two hours. The system is expected to last at least 30 years.