The Mammoth Mountain Snowmaking System

The Key Elements To Making Snow at Mammoth Mountain

To start up the Snowmaking Guns, six key elements need to take place before crews can begin:

Cold temperatures
Low humidity
Compressed air
Water
Snowmaking Guns & Canons
Groomers

The Wet Blub Factor

Aside from air temperature, the Snowmaking staff at Mammoth Mountain Ski Area keeps a close eye on the Wet Bulb temperature. This Temperature is a combination of air temperature and humidity and is the most critical indicator for snowmaking.

A Wet-Bulb Temperature in the low to mid-20s means the Mammoth Mountain Snowmaking Crew can even make snow at or above 32 degrees in some situations.

The bottom line is that the amount of snow made per hour increases as the temperature and humidity drop.

When temperatures are 32 degrees or warmer, the snow they make is like solid cement. It’s excellent base-building snow, but it takes several days to get a run open.

New Snow making Machine - Mammoth Mountain Snowmaking System
Wet Bulb Chart for Snowmaking on Mammoth Mountain

The Simple Process

Multiple Compressors create the compressed air, which is then pushed through miles of snowmaking pipes that line the ski area runs. Parallel snowmaking pipes pump air and water up the mountain to the snowmaking guns.

The Snowmaking Guns and Cannons serve as the mixing chamber for the water and air that blow snow, helping to start and build a base for a long season.

Why Manmade Snow?

Machine-made snow is more durable than natural snow and is essential for ensuring a good base on the main groomed outruns, which give access to five Lodges and Outposts.

Snowmaking is also essential for hosting world-class events in the Mammoth Mountain Unbound. Without snowmaking, the parks that get built would only be possible in the bigger winter seasons.

Natural vs Manmade Snow

Natural snowflakes have six arms, or dendrites, that spread away from the flake’s core. These arms create the symmetrical crystals that make them so pretty—but also make them so fragile!

Machine-made snow, on the other hand, is a simple ball of snow—there are no arms to break off and get compacted down. Thus, it is more durable for creating and maintaining a base and building a World-Class Snow Park. 

Natural vs Manmade Snow
Natural vs Snowmaking Snow

The Snowmaking and Grooming Crew

The final touch in the snowmaking process is the Mammoth Mountain Snowmaking Crew!

They start the season in late Summer, replacing underground snowmaking lines that need repair and laying new pipes in some years to expand the system.

Once the right weather conditions arrive, the snowmaking crew is on call 24 hours a day, seven days a week, taking advantage of ideal conditions the moment they hit the hill.

Snowmaking Crews Work All Night Long

They work all night to prepare the mountain for you to enjoy skiing, riding, and tubing.

Even when we don’t get to make snow on a particular night, the grooming staff will be hard at work all night to get the slopes looking and feeling like they have a nice fresh coat of snow—look at that corduroy!

In conclusion

Snowmaking at Mammoth Mountain involves several departments and millions of dollars in equipment. It all starts with the blessing of ideal snowmaking conditions.

Mammoth Snowmaking History

Back in the so-called good old days, Dave Mc Coy always counted on natural snowfall. When the snow did not come, the Mountain and town somehow always made it through. 

During the 1990/91 season, when the worst of the drought years hit and there was barely any snow to ski on… That’s when Dave decided it was time to pull the plug and build a 200-acre snowmaking system.

Over the course of one fantastic Summer into early Fall, construction crews built a snowmaking plant and a massive reservoir at McCoy Station. They dug and laid out miles of pile lines to run air and water through. 

The price tag for the project that Summer was $5 million; Dave called it everyone’s insurance Policy. With the money they invested, crews could set up and run 50 guns simultaneously. 

That first snowmaking fall, Dave was blessed with some natural snowfall. That allowed the new snowmaking team to learn how to run the new system properly.

The Ski Areas’ New Snowmaking Team quickly dialed in the snowmaking system in the fall of 1991 and used those guns to add base to the low coverage areas.

I found a quote from Dave in a 1991 LA Times write-up on the snowmaking system. 

“If it were to snow 10 feet tonight, I would still say it’s the best investment we could make because it has boosted the morale of our employees. It has brought us closer to the town and the industry. It’s just worth having it. If we never use it again, it’s everyone’s insurance.

“We’ll have about 50 guns going all day. It really helps. We can make the snow just a little wetter now and set a firm base.”

Dave Mc Coy on Snowmaking at Mammoth Mountain
Dave Mc Coy

After that first construction season, the Mountain expanded the snowmaking system a bit each Summer, eventually reaching the Chair 9 and 12 base areas and down to the Little Eagle Lodge.

I always thought it was a fantastic feat they pulled off, laying snowmaking lines from the Top of the Mountain down through the Cornice Bowl and into Saddle Bowl. During a low snowfall in November, you could still be skiing top to bottom on only artificial snow by Thanksgiving; what a concept.

Snowmaking on Cornice Bowl at the Mammoth Mountain Ski Area
Snowmaking on Cornice Bowl at the Mammoth Mountain Ski Area

Snowmaking also became a key factor in building the impressive Unbound Parks, for which Mammoth Mountain Ski Area has been renowned.

If we fast-forward to 2024, over the last several years, Alterra, the current ski area owner, has invested over 10+ million in snowmaking upgrades at the Mountain.

They have laid miles and miles of new line, added dozens of Snow Cannons, and fixed Snowmaking Guns. Now, Broadway, Stump Alley, and Roller Coaster all have those large cannons in place, complete with all-new piping, to ensure a plentiful water flow, allowing them to produce large amounts of early-season base.

During the Summer of 2022, they expanded and installed a brand-new liner in the McCoy Station Snowmaking Reservoir. The new version now holds millions of gallons of water for snowmaking. Along with the rebuilt lake and liner, they also upgraded the pump station located alongside the reservoir.

Updating the Snowmaking Pond

At Canyon Lodge, crews are installing new snowmaking lines and a fixed-in-place system. All these news guns are strategically placed, so the Mountain Loges and Parking areas can run much earlier during the drier Fall Seasons.

New Snowmaking lines at Canyon Lodge
New Snowmaking lines at Canyon Lodge

Having Stump Alley with large canons from top to bottom means the Mill will open much faster and with much better surface conditions than we have seen over the past years.

The other benefit of these snowmaking upgrades is that the system operates at a significantly more energy-efficient capacity, thereby saving a substantial amount on energy usage and overall ski area costs.

The bottom line, IMHO, is that Mammoth Mountain Ski Area has one of the best snowmaking systems in the country. The snowmaking system is the main reason the Mountain has been able to open in early November every year since the Summer of 1991.

Steve Taylor – the Mammoth Snowman

Snowmaking Photos at Mammoth Mountain