Last winter we were reminded of the devastating potential of avalanches, with nine people killed in and around the mountains of the Northwest.

With heavy snowfalls last month, and more expected for January, local authorities are working to ensure necessary preventative measures are taken to reduce the incidence of dangerous snow falls.

Last weekend Department of Transportation Avalanche Control Officers closed a section of Interstate 90 west of Snoqualmie Pass to remove a snow bank which had shown signs of instability.

And more avalanche control work is expected in coming weeks.

According to Avalanche Control Supervisor Craig Wilbour, a potentially hazardous snow bank is disrupted using explosives.

The timing of the blast is all important.

“For the removal to be effective, the snow has to be ready to fall,” Wilbour said.

Identifying hazardous snow banks is a precise science that relies on not just testing of the bank itself but also weather forecasting and geological estimations.

“The critical thing is the forecasting,” Wilbour said.

With more snow expected we are likely to see more avalanche work in mountainous highway areas like Snoqualmie Pass.

“It is difficult to predict when and where we will have to close down a section of road to remove a snow bank,” Wilbour said. “But given the forecast, we would expect that there will be more avalanche removal work in the near future.”

Wilbour said that the two hour closure of I-90 on Sunday was longer than he would have hoped.

“One of the unfortunate things is that the best time to remove the snow is when it is warm, and that is typically in the daytime, when delays on roads are most inconvenient,” he said.