Winter driving can be exciting, challenging and dangerous, all at the same time. I decided to write this short information piece after a small incident up here in the local Whistler back country. The aim of this is somewhat to share the “rules” on groomed back country trails in regard to 4×4 / ATV / UTV winter adventures, by sharing a few insights and years of experience.
The Pre Story
A nice 4×4 that was well equipped decided to enjoy the amazing cold weather we were having by taking a small solo vehicle journey up one of the winter snowmobile trails close to Whistler. The weather had been very clear and cold for a couple of weeks prior to the trip allowing for firm snow conditions and somewhat easy travel.
The trip was going well until the vehicle encountered softer snow and became bogged down and stuck. As the vehicle was solo it was unable to extract itself and became fully stuck.
The owners did the smart thing and flagged down a local snowmobile company who evacuated them out of the back country to safety and civilization rather than them trying to walk out approximately 14km in -20c overnight temperatures.
They then made more good decisions and reached out for help, which is where I came in. I was able to use my local trail knowledge, contacts and experience to connect the owner of the 4×4 with the local company and one of its highly experienced snow cat operators who was then able to help recover the stranded vehicle.
The weather had changed dramatically and it started to snow vast amounts of snow between getting stuck and before being recovered. Probably in excess of 50cm overnight in the region where the truck was stranded. Without the aid of the snow cat, the vehicle could have been stuck there for the season until summer thaw.
Below is a little video and a few images of the recovery.
Snowmobile, dog sled and cat skiing companies in British Columbia require to operate under a legal tenure which entitles them to exclusive commercial operations within that tenure zone. There are many considerations that they take into account and many regulations that they have to adhere to to ensure safe and environmentally considerate operations.
Do not drive on trails used for snowmobiling, dog-sledding and cat skiing.
These trails are often on crown land and are open to everyone to use during regular summer none snow months, in a none commercial capacity. In fact they are open to the public year round, however during snow months there are often trail fees for any public users, that goes towards maintenance, parking, plowing, grooming etc. These trails then become essentially closed to none snow travel vehicles (rubber tired vehicles) and are only open to snowmobiles, snow bikes, snow cats, dog sleds, tracked atv’s & tracked utv’s.
The snow surface that snowmobile, dogsleds and cat skiing operations is absolutely vital to the safety and enjoyment of the public and paying guests that use them.
As soon as a rubber tired truck / atv / utv drives on a trail that is used for snow activities then the surface does get almost certainly destroyed or damaged and made unsafe for those trail users that rely on a flat safe surface. Ruts are formed, holes are made that are a significant danger to snowmobiles, dogsleds, skiers and snowboarders. If these ruts are not removed by snow cat grooming they can freeze into the surface and become even more dangerous.
Snow science is a complicated matter but essentially a heavier vehicle traveling up a trail can make ruts and bumps even in the firmest of snow surfaces. What happens is that the weight of the vehicle and the friction it creates, warms the snow slightly. This slight warming allows the ruts and anomalies to form. As soon as the vehicle moves on the ambient air temperature, humidity and latent cold within the snow causes the snow to start to firm up. This can take several hours, but once the snow has firmed up, the anomaly or rut is set into the snow. This can then be of great danger to the winter trail users. Obviously there are many factors that affect the severity of the ruts that a vehicle leaves including snow density, temperatures, snow structure, vehicle weight, tire size etc etc. No matter what, rubber tired vehicles make about the most dangerous rutting to winter trail users.
A snow cat with a tiller has the ability to fix these ruts, however it takes time, it is an expensive machine to run and at the very maximum happens once a day. A snow cat with a tiller can use its blade to contour the trail and the tiller leaves the finished surface. The tiller is essentially a high speed hydraulic toothed drum that smashes the snow crystals apart with the teeth within the tiller chamber, heats it up and then lays it down using finisher bars to leave the iconic corduroy that winter trail users rely on for safety and enjoyment. The snow then takes several hours of cold temperatures to set up / firm up and become solid to the finished surface. Any travel on the surface immediately after a snow cat has done its job will wreck the surface.
Tracked vehicles and dog sleds are designed to spread their weight over a greater surface area and to “float” on the surface trying to reduce how much they dig in. Of course it happens no matter what but they are designed to slide along the surface leaving the least impact as possible. They way they are designed to slide is to bite slightly into the snow and run in self created grooves. Any larger grooves or ruts can cause the path of travel to be deflected dangerously.
Groomed trails are also very deceptive and often hide hidden dangers to vehicles on rubber tires. Tracked snowcats spread their weight over a vast area and are able to float somewhat on the snow. When we build and groom trails we often build over cross ditches, water bars, soft ground, trees, stumps, creeks and much more. These dangers are lurking below and can often be punched through to with vehicles that can’t spread their weigh adequately. The groomed trail is often smooth and looks safe, where as a natural un-groomed trail will shows it’s dangers by natural snow fall contours and settling.
There are thousands of kilometres outside of these tenured winter activity zones that are free and open to use for rubber tired winter travel and fun. Hopefully these few words and this recent true story can help encourage respectful trail choices and use.