Traffic and Avalanche Hazard- The Realities of Getting up the Cottonwood Canyons


It’s a tale as old as the Avalanche Forecast:

“A good old fashioned cold front crashed through the Wasatch last night and snow totals are up to a foot (12″/0.86″SWE) in the Cottonwoods and the northern end of the Park City ridgeline. It’s still snowing”…(UAC Avy Report 12/4/2017)”

Knowing it is dumping in the mountains – You get up before dark, gear up, load up and head to the mountains. But your dreams of first chair and first tracks – floating through the greatest snow on earth – come to a literal, screeching halt as you sit in a long line of cars impatiently waiting for the road to open. While you sit in traffic waiting to recreate, the blocked roads interfere with commuters who live in the canyons and communities at the mouth trying to get to work or school and local businesses not to mention that emergency vehicles like fire trucks and ambulances are not able to respond to emergencies through miles of blocked roads. Finding a solution to the traffic and blocked roads while trying to access Little Cottonwood Canyon is more complex than keeping the road open on powder days.

Dave Fields the General Manager of Snowbird, says traffic has been an issue in the canyons since the days of mining, as there has never been an easy way to get up and down Little Cottonwood Canyon. “I drive up – essentially, the same canyon road every day to work as I did in 1975 with my parents. A few passing lanes have been added, but for all intents and purposes the road hasn’t been changed in decades, despite an increase in vehicle traffic and a growing population along the Wasatch Front.” The road is at risk for closure or traffic back-up due to a change in weather conditions, rock fall or traffic accidents, to name but a few reasons. As there is no bypass to the canyon, if anything blocks the road, everything comes to a complete stop and no one goes up and no one goes down until the issue is resolved.

UDOT is in the process of conducting an Environmental Impact Study (EIS) in Little Cottonwood Canyon (LCC). The EIS will, “evaluate potential improvements that reduce peak congestion and improve recreation and tourism experiences.” According to the draft of the Coordination Plan the improvements include; “managing the number of vehicles on the road system, improving vehicle mobility, and improving roadway safety and reliability for all users, while reflecting the character and scale of Little Cottonwood Canyon.” Factors that have contributed to the traffic problems are both growth in population in Salt Lake and surrounding areas, as well as increased recreational use. Annual growth in canyon visitors grew by 3% in the winter and by 8% in the summer from 2012 to 2015.

The proposed improvements being considered include adding 800-1000 parking spots at the gravel pit on Wasatch Boulevard, an additional 200-300 overflow parking spots at the intersection of Fort Union and Wasatch Blvd, along with pedestrian walkways and bus pullouts, multi-level parking at the base of LCC and pedestrian walkways, along with multiple improvements in LCC including, snowsheds to protect the road from avalanches, widening the road, traffic lights, tolls, intersection modifications, bus pullouts and increased parking at White Pine.

2019 will see the creation of a Draft Environmental Impact Statement and will wrap up with a public hearing and a 45-day comment period in summer of 2019, with hopes to have a final EIS in spring 2020.

There are multiple problems related to the increased recreational visits in the canyon including overflow and roadside parking that affect natural resources, road safety, aesthetics and the user experience. Carl Fisher, Executive Director of Save Our Canyons says addressing the traffic problems should start with asking what is it about the Canyon’s that’s the most important to people? “Is it the watershed? Is it wildlife? Is it just being able to go there whenever you want to go there? I think people really need to make that clear to the agencies that are looking at transportation in the canyons, because I think those things inform our choices and ultimately the decisions that will be made.”

The worst-case scenario, says Fisher is if there is something like a train or a gondola, something that’s really high capacity, going up Little Cottonwood Canyon or either of the canyons. “ We’ve tried to challenge a lot of entities like UDOT, UTA, the ski areas and local leaders, to say, it’s not about what you do up and down the canyons, it’s not what we do through the canyons; it’s what we do to the canyons because you have a bottleneck effect right? We have in Little Cottonwood Canyon for example, I think it says like, at it’s peak there’s something like nine and ten thousand vehicles on the busiest of days in that canyon. Well, if you have a gondola or a train or a third lane with buses and vehicles, you still have these ten thousand vehicles trying to get to the mouth of the canyon.”   Fisher states that we need to be expanding our perspective and not just to look at SR 210 and Little Cottonwood but look at how/where people are originating from and coming, because we don’t want the mouths of our canyons to turn into massive sky rises with parking centers, and it’s unlikely that the communities that are at the mouth of the canyon want that either.

Fisher notes that while infrastructure projects need to happen, there are pros and cons to each one of the kind of ideas that are being considered. But he adds, “at the end of the day for us, what we think we have more than anything is a behavioral issue with the people that rightfully so want to be in these canyons. I mean, who could blame you for wanting to go up there on a powder day and making some turns or going up there in the summertime to escape the heat, I think we can see less infrastructure in the canyons, if our community changes their behaviors. Start carpooling and start believing in mass transit now, we need some infrastructure to help support that.”  Fields says that Snowbird is a strong advocate for carpooling, which they’ve incentivized with an app, and uses shuttle buses and vans for employees and guests. But Fields is quick to note that these efforts while helpful don’t come close to addressing the problems that occur on peak days. The infrastructure to help reduce the number of cars on the road is currently serviced by a public transport system that falls short of providing a viable transportation option. Recreationalists trying to use the ski bus still face inadequate parking, lack of amenities at bus stops, limited service times, crowding at peak times and no bus service in the fall or summer. Improving public transport will help users who want to access the ski resorts, but what about backcountry users?


Chris Adams, Board President of Wasatch Backcountry Alliance and a homeowner in Big Cottonwood Canyon, is concerned that the proposed traffic systems, the efficiency of getting more people in the canyon will be so successful that day users will increase in the next decade from 10,000 to 20,000 per day and will degrade the experience of the canyons. Adams wants people to be aware of what’s happening, knowing what infrastructure changes and solutions are being talked about and he encourages public engagement, and for recreationalists to voice their concerns and ideas. He’d like to see public transportation provided for dispersed backcountry users that want to access the canyon at different points in Little Cottonwood throughout all seasons.

To Contact UDOT and Learn about the EIS:

Comments for the EIS can be made at:

AVALANCHE CONTROL: Road Closed, Backcountry Restricted

What’s Going On When the Road is Closed?

Millions of recreationists each season travel over the 64,000 linear feet or 53 miles of state highway that is under the threat of approximately 250 avalanche paths on their way to resorts or backcountry skiing. Those threats are spread out over 14 state highways. Of the 14 highways the 5 main roads that are managed for avalanche threat lead directly to the above mentioned greatest snow on earth… Powder Mountain SR 158, Big Cottonwood Canyon SR 190, Little Cottonwood Canyon SR 210, American Fork Canyon SR 92 and Provo Canyon US 189.

Roadways in Utah are managed for avalanche threat by the Utah Department of Transportation (UDOT) who employs 10 Full-time avalanche forecasters and another 40 part-time avalanche technicians who are called in as needed to perform avalanche control work says Bill Nalli, UDOT’s Avalanche Safety Program Manager.

A snow safety and avalanche forecast professional for over 2 decades, Nalli’s resume includes being a ski patroller at Solitude, backcountry guide in the Central Wasatch, a snowcat and heli-ski guide in the Uinta Mountains and avalanche educator for the American Avalanche Institute. In 2004 Bill began working as an avalanche forecaster with UDOT in Provo Canyon and was the supervisor for that area until 2013, when he moved back to the Central Wasatch as a forecaster in Big Cottonwood. In 2014 he became the Avalanche Safety Program Manager. While much of his time is spent in Little Cottonwood Canyon, managing the avalanche issues for all of Utah’s state highways keeps him moving around from Logan Canyon to Powder Mountain, Big and Little Cottonwood, American Fork and Provo Canyons, and south to Huntington and Cedar Canyons.

But the heart of the UDOT program is in the Cottonwoods and Provo where frequent avalanche events hit the roadway. These avalanche events come in varying sizes, but if it blocks traffic it causes problems; as cars back up and people get out of their cars who are then exposed to additional avalanche danger. UDOT minimizes the number of open avalanches on the road by paying very close attention to the snowpack from the onset of the first snow until the snow melts in the spring. UDOT forecasters analyze the snowpack and the layers and when they decide that the slopes are unstable, they manage this threat by closing the road to perform avalanche control work. If the avalanche threat and subsequent control work is on land owned or managed by municipalities then the access is closed by statutes on the basis of public safety.

When it’s time to perform avalanche preventive release work, one of the biggest challenges is to clear the area of the people, says Nalli because no one wants the road closed for long. As we know, on any given winter day in Utah there are alot of people, cars and backcountry skiers that want to recreate and UDOT is trying to get closure information out in every way they can. UDOT wants people to have the info about where avalanche work is taking place not only so they don’t have to wait in traffic, but also so they don’t get hit with shrapnel, yeah shrapnel.

One of the best tools used in avalanche preventive release work is artillery, which has been used in LCC since 1949. Artillery delivers a large explosion and is accurate over a long distance, but it does have a risk as it shoots a 105mm steel bullet that blows up….with shrapnel traveling up to 800 yards. So not only does the path of the avalanche have to be clear, but the area around the detonation up to 800 yards has to be clear as well, which means closing a large area. There are 64 named avalanche paths in Little Cottonwood Canyon…..but within those paths there are multiple starting points that result in 120 artillery avalanche targets.

UDOT does control work frequently to minimize the size and frequency of avalanches. Frequent control work reduces the chance that big avalanches hit the roads or the buildings. At least in in LCC it’s not just the roadway that needs to be kept clear of avalanche threat, there are also 51 buildings are threatened by avalanches. By doing avalanche control work regularly, UDOT is also stewards for keeping those buildings safe.

When control work is planned; the location, date, time and a map that shows the boundary of the closures is posted on the UDOT website, emails are sent to public safety agencies and resorts, signs are posted at the mouth of every road that update with information about upcoming closures, closures are posted at major trailheads and real time posts are available on social media. UDOT isn’t alone in trying to keep the public informed, the town of Alta hires people to wait on the road…starting at 3am…they sit in cars and wait to see people who are heading out to do a tour and they let them know about closures. Before shooting UDOT uses thermal imaging to scan the slope for people and while they can see in the dark, they can’t see through the snow in a storm. Still, says Nalli, “Each time we go to shoot, especially in LCC people still get through these layers….the growing population of dawn patrollers are on the ridge lines at dawn, the same time we need to shoot…..but it’s not only them, it’s all backcountry users, that need to have our information.”

UDOT is one of 18 programs in the United States that use artillery for avalanche control,
and the US Army governs them by how and under what circumstances that they can use this tool. Any problems that occur; an accident with the weapon, problems with the ammunition…someone getting hurt…they risk having their program shut down. And those are simply not options for UDOT at this point in time. UDOT is working to reduce dependence on artillery, but Nalli says, “I don’t see a day when we ever don’t need it.”

In their effort to reduce dependence on artillery, UDOT has implemented the use of Remote Avalanche Control Systems or RACS in areas that are not suitable for artillery or easily accessible to technicians for hand charges. RACS are positioned at avalanche starting points and are activated remotely. Currently UDOT uses the GAZ-EX and the O’Bellx self contained systems in LCC. GAZ-EX uses a mixture of propane and oxygen and O’Bellx uses hydrogen and oxygen. A spark is introduced to the gas mixture and an air blast is large enough to trigger avalanches. These systems can be remotely activated regardless of weather conditions 24 hours a day and are self contained during the season. Due to the remote activation and placement in hard to access areas these devices reduce the amount of time it takes to perform control work.

In summer 2017 UDOT added 5 new GAZ-Ex exploders in the Blackjack area, that have reduced the amount of time it takes to perform control work from 1 hour to less than 5 minutes. These systems are more efficient and safer, they can be used in off hours, technicians are not deployed into the field and they reduce artillery targets that fire over inhabited buildings. In addition to GAZ-EX and O’Bellx, UDOT also uses a Wyssen Tower in LCC. The Wyssen Tower is a remotely deployed charge that has twice the blast radius of the GAZ-EX. The Wyssen Tower in LCC is the 1st one in the US, but there are hundreds in use throughout Europe. Nalli says he’s excited for what these systems can mean for avalanche safety in Utah, “We can’t shoot artillery at everything, and we can’t deploy teams to all areas, so these systems give us options.”  This past May UDOT begun construction of eight Remote Avalanche Control Systems (RACS) to be permanently installed in the starting zones above the Hellgate cliffs.

Artillery, hand charges and propane blasts are known as active avalanche control work, but they aren’t the only tools that can be used; there are passive methods that can be used as well. Even with a skilled team, like UDOT has in place, avalanches can still hit the open road. White Pine in LCC is one such area that is known to release naturally and hit the road even after having control work performed. Passive methods like a snow fence work by keeping the snow in place when a release happens, but they have other issues. The #1 issue is that snow fences stop skiing, and they are also a permanent in place year round structure. Nalli notes that he doesn’t think snow fences have a place in the UDOT program in LCC, but says they are looking at structures that could protect the run out zone- where the avalanche hits the road – and could protect areas at risk, but at this time they have made plans to implement any structures.

In addition to active and passive avalanche control methods UDOT also uses radar and infrasound (IDA) avalanche detection systems. Every 90 seconds the systems sends out a new batch of information, so forecasters get a picture of where avalanches are happening. This activity can be monitored in the office in real time and can help determine where to shoot or how to correct shots for maximum effect. Currently there are only 2 systems like this in the world, UDOT’s in LCC and 1 in Wyoming. The LCC systems is set upon 6 paths, and they are looking to expand it by actively fostering research to create the next generation of radar and infrasound.

For backcountry closure information related to avalanche control.


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