The Trans-Canada Highway crosses the Selkirk Mountains of British Columbia at Rogers Pass, an elevation of 1,330 metres, and runs for forty-three kilometres through terrain in which one hundred and thirty-four named avalanche paths reach the road. It is the most actively managed avalanche corridor in North America.
On the morning of 6 February 2026, the avalanche control team at the Parks Canada operations centre in Rogers Pass village was assembled at 0445, drinking coffee from a battered urn, looking at the previous twenty-four hours of weather data.
The lead forecaster on shift was Adeline Pruneau, 41, who has worked at Rogers Pass for thirteen years. She is one of nine senior forecasters in the program. The decision before her was whether to close the highway for control work, and if so, at what hour and for how long.
The highway had received forty-eight centimetres of new snow at the pass overnight. Winds had been moderate from the south-west. Temperatures had remained well below freezing. The previous afternoon's forecast had rated the avalanche hazard High at upper elevations and Considerable at the highway.
Pruneau, with the second forecaster on shift, a Quebecois named Rémi Bergeron, reviewed the storm board, the snowpack summary, the weather forecast for the day, and the closure history of the previous week. They concluded, at 0512, that control work was warranted on a subset of paths above the western approach to the pass.
The highway would close at 0700. The work would begin at 0730. The road, if all went well, would reopen by noon.
Avalanche control at Rogers Pass is performed primarily by artillery. The program operates, by special arrangement with the Canadian Armed Forces, a battery of 105 millimetre howitzers that are fired into the start zones of selected avalanche paths to release the snow before it can release on its own. The program is the only civilian use of military artillery for snow control in North America.
On the morning of the 6th, the gun crew assembled at the firing position above the highway at 0651. The crew chief was a master gunner named Sergeant Marcellin Doiron, on a five-year secondment from the Royal Canadian Horse Artillery. His team consisted of three soldiers and one Parks Canada observer.
The artillery, despite its scale, is in some respects the simpler part of the morning. The harder part is the decision about what to fire and when.
Pruneau's role in the control mission is to specify each target. The targets are identified by name, elevation, and a coordinate that has been pre-surveyed and entered into the gun's fire-control system. Each target requires a particular sequence of rounds, sometimes three, sometimes seven, sometimes more, depending on the size of the start zone and the day's instability assessment.
She specified, that morning, twenty-eight targets across nine paths. The mission would require approximately 134 rounds of ammunition. The estimated firing time was forty minutes.
The first round was fired at 0734 local. It impacted the upper start zone of a path called Cougar Corner, on the south flank of Mount Tupper, and produced a release that ran about six hundred vertical metres and stopped well above the highway. Pruneau, watching through binoculars from the observation position, noted the result in her tablet and confirmed the next target.
By 0902 the gun crew had completed twenty of the twenty-eight targets. The mission had produced fourteen avalanches of significant size, including two that crossed the highway corridor and deposited debris up to six metres deep on the road surface. The other six targets, when fired, produced smaller results or no result, which Pruneau interpreted as evidence that the snowpack on those particular slopes was either more stable than expected or had already released naturally during the storm.
The mission ended at 0934. The road was opened to highway maintenance crews, who began clearing debris with two graders, a snowblower, and a front-end loader. The road reopened to traffic at 1218, six minutes ahead of the morning's estimate.
Pruneau drove home, two kilometres from the operations centre, slept until 1500, and returned to the office for the afternoon's planning meeting.
The Rogers Pass avalanche control program closes the highway for an average of about ninety hours per winter, distributed across roughly thirty separate control missions. The closures cost, by various estimates, between four and eight million Canadian dollars per year in lost commerce, freight rescheduling, and delayed travel. The program also, by the same various estimates, prevents between one and three highway fatalities per year.
The cost-benefit calculation, when performed in the formal language of transportation economics, is uncontroversial. The program pays for itself many times over.
The calculation is also, when performed by the people who fire the rounds, somewhat beside the point. The gun crew and the forecasters speak about specific avalanches and specific decisions, not about averages.
Sergeant Doiron, who has worked at Rogers Pass for three of his five years, said in a brief conversation after the 6 February mission that the part of the job he found most interesting was the relationship between the gunners and the forecasters. The gunners, he said, were trained to put steel on target. The forecasters were trained to decide what target deserved steel. The conversation between the two, conducted in the cold and the dark before each mission, was the part of the work he respected most.
He said this while disassembling and cleaning a part of the howitzer's recoil system, with a rag and a small tin of oil, in the warming shed.
The 2025-26 control season ended on 14 April with the final mission of the year, which targeted three lingering glide cracks above a particularly exposed section of the highway. The gun was put away for the summer. The forecasters moved into the spring monitoring schedule. The road remained open.
Pruneau, asked at the end of the season whether she felt the year had been a success, said that no one had died on the highway during a closure or during an opening, that no piece of equipment had been seriously damaged, and that the artillery battery had fired six hundred and forty-one rounds with no malfunctions. She said this was the definition of a successful season she preferred.
