Glacier Park: Sperry Chalet flyover shows dormitory walls intact under record snowpack

Aerial photographs of Sperry Chalet show its 2-foot-thick walls intact, despite an intense winter snowpack. (Gravityshots.com via Glacier National Park Conservancy)

Photographs from a flyover of Glacier National Park’s Sperry Chalet this week show last fall’s post-wildfire stabilization efforts have thus far protected the historic dormitory’s remaining stone walls from collapse under a record snowpack.

Late Thursday, the Glacier National Park Conservancy released photos and a video from the flyover – the first of three planned and financed by the conservancy this winter.

The spectacular shots, taken from a fixed-wing aircraft, show an incredible landscape of snowy mountainsides and peaks surrounding the 103-year-old chalet, which burned in a ferocious Aug. 31 wildfire.

Even as the fire continued to burn, the National Park Service asked the nonprofit conservancy to raise $106,200 for a structural assessment of the chalet’s remaining stone walls, the creation of a stabilization plan, purchase of the needed building materials and their transportation to the site, and the pre-snowfall stabilization work.

Because the fire consumed the building’s roof and floors, it was at increased risk of collapse. By the time work started, donations to the conservancy’s Sperry Action Fund totaled nearly $108,000.

A crew of 10 flew to the chalet in early October and, as the first flakes of snow started to fall, braces the badly damaged structure’s walls, gables, windows and chimneys.

The goal: to protect the chalet’s stone masonry walls from winter’s heavy snow loads and high winds.

According to Glacier Park officials, the crew of NPS workers placed 100 16-foot 6-by-6 beams, 24 24-foot 6-by-6 beams, and 24 sheets of three-quarter-inch plywood. It took 15 helicopter trips to transport the materials. Each beam weighed 140 to 180 pounds, depending on length.

In Thursday evening’s announcement, Glacier Conservancy director Doug Mitchell said this week’s flyover showed what both his organization and park officials hoped.

“It appears that, thus far, those (stabilization) efforts have been successful, and that no extreme events like avalanches have occurred,” Mitchell wrote the conservancy’s supporters.

A fixed-wing aircraft flew over Sperry Chalet this week to inspect the structure four months after stabilization and in the midst of a record winter snowpack. (Gravityshots.com via Glacier National Park Conservancy)

“From this vantage point, it appears that the stone walls have thus far withstood the winter weather and discussions about the next steps for the building are continuing,” he said.

The Sperry Action Fund will finance two additional flyovers this winter as well. The first flight would have been sooner, Mitchell said, but was delayed for weeks waiting for favorable flying weather.

Glacier Park’s high country has seen a record amount of snowfall this winter, with the SNOTEL site on Flattop Mountain reporting a snow depth of 122 inches as of Thursday. That’s 38.3 inches of snow-water equivalent, or 116 percent of the 30-year average.

Last fall, a structural analysis by DCI + BCE Engineers (which also consulted on repairs to the chalet after it was damaged by an avalanche in 2011) found the chalet’s remaining stone structure to be sound but warned about the likelihood of damage from winter’s snow load and typically high winds. (Glacier Park has recorded winds of up to 139 mph at the unmanned weather station atop Logan Pass.)

“That known, our goal was before winter sets in to provide stabilization of those walls,” said Glacier Superintendent Jeff Mow. “That gives us the opportunity to think about what does the Sperry Chalet for the next 100 years look like. There will be a lot of discussion about that piece over the winter.”

“The stabilization would not have been possible without the conservancy stepping up to the plate and helping hire the structural engineers, purchase the stabilization materials and underwrite the expenses related to the labor,” Mow said. “If we had to go through the government contracting process, and rehire our summer employees, we could not have gotten the work done before winter.”

As the Sperry Chalet’s future is determined, the conservancy has pledged to continue raising money for the necessary work.

“We’ll keep going, piece by piece,” said Nikki Eisinger, the nonprofit group’s development director.