Massive Sinkhole Devours Snowmobile

AmSnow test rider narrowly escapes death as his sled plummets 75 feet

Utah sinkhole Ski-Doo snowmobile sled extraction recovery
While riding in northern Utah, AmSnow test rider Lonnie Thompson had to bail when he came upon this unexpected sinkhole. Thankfully, he made it out of this hairy situation unscathed. The sled, however, went down, and an entire crew of 12 people, including mountaineer Matt Jensen (above), went in to recover it a week later.
Ryan Thompson – RLT Photos
AmSnow Western HQ, Hyrum, Utah – Our test riders and I often ride in an area of northern Utah/southern Idaho that is dotted with sinkholes. In fact, the largest sinkhole in Utah, and possibly in the U.S., is still being mapped out here and known as “Main Drain." It is over 1,100 feet deep and is located up in a place called Tony’s Grove. As the crow flies, that’s not that far from the sinkhole where AmSnow test rider Lonnie Thompson’s sled went in. We are used to seeing a lot of sinkholes and know where most of them are, as they are usually pretty easy to spot. But this was not this case this time.
Utah sinkhole snowmobile sled extraction recovery
Avid rock climber Matt Jensen rappelled approximately 115 feet into the sinkhole to retrieve the lost sled.
Ryan Thompson – RLT Photos

On April 30, there was a group of us out riding, and toward the end of the day we headed over to a place we call “no man’s land.” Lonnie was on a ridge looking for a spot to drop down through the pine trees to the bottom and he was the first to drop off the hill. The snow was very wet and heavy, so he generated a lot of speed coming off the hill, not to mention it was very steep. About 50 yards down, he came over a small hump in the snow, and that’s when he saw the sinkhole.

At that point, Lonnie bailed off knowing there was no way to save or stop the sled. The sled went airborne and slammed into the side of the sinkhole before it dropped approximately 50 feet down and got hung up on the rock wall. There it was dangling with another 60 feet straight down if it came loose. In the meantime, Lonnie had landed on the downhill slope of the sinkhole, slid and stopped just mere feet away from the edge where it dropped straight down. It was like something out of a sci-fi action film! Had he gone in the hole, it most likely would have killed him due to the massive drop and jagged rocks. Given Lonnie’s downward momentum and the steepness of the slope, it was nothing short of a miracle that he didn’t go in.

On a side note, this was only a few miles from where my dad had died a year earlier. Lonnie was there when that happened as were a lot of the people in the group. Needless to say, this brought back a flood of memories for everyone involved, and it was a pretty somber moment knowing how close Lonnie came to meeting the same fate. Lonnie’s dad (my dad’s brother) was with us as well when we accidentally found this sinkhole, and he was quite emotional about the event, having lost his brother and now almost losing his son in the same area.

We did not even attempt to extract the snowmobile the first day, since emotions were too high and the right equipment was not at hand. Instead, we decided to come up the following Saturday (May 7) with everything needed for a safe recovery of the sled.

Utah sinkhole snowmobile sled extraction damage
Falling into the sinkhole caused damage to the sled, but not as much as we had expected.

We took a group of 12 riders with rappelling equipment and hardware back to the spot. Matt Jensen, who rides with us and is an avid rock climber, rappelled into the hole and attached straps to the spindles and a rope on a pulley from a ratchet line that was stretched across the hole. With some rigging and other pulleys, we extracted the sled from the hole by hand (scroll down to see a video and a photo gallery of the recovery). Matt estimated the sinkhole to be roughly 115 feet deep based on the rope length.

Surprisingly, the damage to the snowmobile was not as bad as we expected, and had we been able to find the tether, we could have probably started it and rode it out. Luckily, Lonnie’s Mountain Dew was still intact in the bag on his tunnel – a bit shaken, but nice and chilled.  

After getting the sled out of the hole, we had to maneuver it about 100 yards to get it up the hill. This was done using pulleys and a rope hooked to the back bumper of a snowmobile that drove downhill to pull the disabled snowmobile uphill.  The rope and pulley had to be reattached several times until the sled was at the top. From there, it was towed out along the easiest available route. Because we had a lot of snowmelt last week, we had to take a truck with a sled deck up the road to meet them. They had to come out a way we normally do not take this time of year, but it was the only possible route out.

The crazy part of all of this ordeal is that it happened in an area frequented very often by sledders like us, yet it was the first time anyone had seen the sinkhole that was located in an unusual spot on the side of a steep hill. We guessed that maybe during most winters it gets totally drifted and snowed over, which is why it has not been seen before. Had someone been coming uphill, they would have never seen it until it was too late. Looking from below, over the horizon of the hole, it blends perfectly with the other side, making it look like it is just a part of the hill.

Scary, crazy, amazing stuff, but it made for an unbelievable story and a day on the hill that none of us will ever forget.

Story, photos and video content provided by Ryan Thompson, RLT Photos


Ryan Thompson – RLT Photos
The recovery crew waits patiently as Matt Jensen rappels into the sinkhole to extract the sled.
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