An unknown dark object in the debris field of an avalanche in a couloir off Black Mountain near Loveland Pass prompted an emergency response from the Summit County Sheriff’s Office on Wednesday, March 22.

But a drone deployed to survey the avalanche quickly determined the object was not a buried person. The incident happened while the Colorado Avalanche Information Center reported moderate to high avalanche danger throughout the state in recent days

“We treat all avalanches like they’re real,” Summit County Sheriff Jaime FitzSimons said. “We treat them all like someone is buried.”

A pair of skiers triggered the avalanche a little before 3 p.m., according to FitzSimons, who said ski patrol at the nearby Arapahoe Basin Ski Area reported the slide. The two skiers did not report the avalanche to emergency responders as they should have, he said.

“It is so important to report these,” FitzSimons said. “You will not get in trouble if you report an avalanche. We want to make sure everybody is safe and alive and you can stop a massive (emergency) response if you were just to call it in.”

When a person triggers an avalanche but doesn’t report it, others who see it but don’t know whether someone could have been trapped also report it, FitzSimons said, prompting an emergency response that may be unneeded.

A failure to report can put emergency responders in harm’s way unnecessarily, he said, since rescue volunteers and law enforcement officers may have to traverse through avalanche terrain or deploy excess resources even though the people who triggered the avalanche know no one is buried.

“You’re the one who caused it,” FitzSimons said. “Your information is more pertinent than anybody’s.”

In this instance, thermal imaging from the drone determined that the unknown object had no heat signature and was probably a rock dislodged in the slide, FitzSimons said. So, Summit County Rescue Group never had to investigate the scene.

Drones, FitzSimons said, “have really changed the game for these avalanche responses.”

The ability to fly a drone with a thermal imaging camera over a debris field soon after an avalanche has made it faster to determine whether someone is buried, he said, meaning rescue teams, avalanche dogs and helicopters have to be deployed less often.

Still, it is important to report avalanches as soon as they happen because — especially when ski tracks are present, such as in this instance — responders don’t know whether someone could be buried, and if someone is, every second counts, FitzSimons said.

When reporting an avalanche, call 911, he said, and notify emergency services whether anyone is buried and the location of the slide with GPS coordinates, if possible.