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Snow Biz

Winter 2007 | Volume 22 |  Issue 3
A blizzard of artificial snow is blown onto a ski slope in Telluride, Colorado, in 1990.karl weatherly/corbis2007_3_32

How a handful of entrepreneurs found a way to make artificial snow and revolutionized the ski industry.

In 1949 if anyone knew about new england winters, Walter R. Schoenknecht did. He was a ski-industry pioneer, the founder of the Mohawk Mountain ski area in Cornwall, Connecticut. In previous years he had watched helplessly as snow melted away in a midwinter thaw or washed away in a rainstorm.

That January, facing another almost snowless winter, he decided to do something about it. Knowing that ski jumpers had on occasion used shaved or crushed ice to cover the takeoff hills, he spent $3,500 to have 500 tons of ice trucked in to Mohawk. Then, using an ice crusher, he and his staff spent three and a half days breaking up the blocks and spreading the chipped ice over a 1,600-foot slope. That weekend, while neighboring operators complained about the weather and hoped for a better season next year, Schoenknecht sold tickets. His solution to the problem was expensive and inelegant, and the chipped ice melted quickly, but whatever he lacked in practicality he made up for in industriousness and sheer audacity. (In 1963 he even petitioned, albeit unsuccessfully, the United States Atomic Energy Commission for a permit to conduct an underground nuclear explosion to create a Rocky Mountain–style ski bowl at Mount Snow, Vermont.) “The important thing,” he wrote in 1950 in The American Ski Annual and Skiing Journal , “was that there was good skiing, and that the skiers were happy.”

Actual snowmaking, the mixing of air and water to produce snow, got its start in late 1949. Three aeronautical engineers, Wayne Pierce, Dave Richey, and Art Hunt, of the Tey Manufacturing Company, in Milford, Connecticut, had gone into the ski-manufacturing business, developing, among other things, the first laminated aluminum skis. In December 1949, as New England ski areas suffered yet again, Pierce began wondering if he could make something resembling snow by throwing droplets of water through freezing air. Experimenting with a garden hose, a 10-horsepower compressor, and a spray-gun nozzle, he succeeded. After substantial testing, in which the team produced up to 18 inches of snow a night outside their plant, Pierce applied for a patent in December 1950. It was granted in 1954.

To prove that the invention could mass-produce snow, Pierce turned to Schoenknecht, at whose area he regularly skied, and Schoenknecht was more than happy to let him build a prototype layout at Mohawk. Pierce contacted Larchmont Farms (later Larchmont Engineering), of Lexington, Massachusetts, an agricultural irrigation company with expertise in moving large volumes of water, whose owners, two brothers named Joe and Phil Tropeano, were also avid skiers. Using Larchmont’s pipes and high-volume water pumps, Pierce hooked up a large diesel-powered air compressor and a series of nozzles. The system cost $25,000 to install, and he had it in place for the 1950–51 season. It could develop 3,000 cubic feet per minute of compressed air, pumped through “two miles of four-inch aluminum pipe and a mile of green plastic hose in varying diameters,” as a ski magazine put it, crisscrossing Schoenknecht’s nine-tow ski area. Similar systems were also installed at Split Rock Lodge, in White Haven, Pennsylvania, and the following winter at Grossinger’s, in Liberty, New York.

The setups were a publicity coup for the ski areas, but they were far from technically successful. “There were problems we had to resolve with the system design,” recalls Phil Tropeano, now 84. For one thing, irrigation systems weren’t designed to work in freezing temperatures, so water tended to back up and freeze in the pipes. Also, air from the compressors would cool as it expanded and freeze up the nozzles. The operators at Split Rock Lodge carried out “semi-desperate experimentation,” as they put it, before abandoning their system altogether. The operators at Bousquet Mountain in Pittsfield, Massachusetts, subsequently ordered a system, and when they turned it on for testing in 1956, “the above-ground network of aluminum pipes simply blew up, tossing a flock of pipes high in the sky,” in the words of a reporter. Later they were able to put it in working order.

Despite such setbacks, and despite well-justified skepticism among ski-area operators, snowmaking was not about to be abandoned. It was too badly needed. It took years of tinkering and trial and error, but ultimately it would revolutionize the sport, changing everything from the timing and length of the season to the design and layout of trails and the quality of surface skiers expected.

Real snow, the kind that falls from the sky, forms when water vapor in clouds cools to near the freezing point. Once it freezes, nascent snow crystals continue to blow around the cloud, allowing other water molecules to attach to them. When a crystal becomes heavy enough, it falls to earth in the form of a snowflake.

Snowmaking is a highly abbreviated version of this process. Water is mechanically atomized, generally by using compressed air, special nozzles, or a combination of the two. The droplets are then flung into the air, where, if it is cold enough, they freeze into tiny pellets of ice, forming something like, if not identical to, natural snow. If compressed air is used, its expansion helps cool the droplets.

Before snowmaking, the best that ski-area operators could do to generate an adequate base was either to shovel or bulldoze snow into large piles that could then be pushed around or to install fences behind which snow might pile. Some resorted to covering trail sections with straw or pine needles to shield them from the sun—or at least make bare spots less conspicuous. Most ski trails, especially in New England, were paths narrowly cut through tall trees, limiting exposure to the sun and wind.

Faster, higher-capacity ski lifts developed in the 1960s held the promise of accommodating legions of new skiers, but the unpredictability of the weather limited the sport’s growth. Snowmaking changed everything. It grew into a competitive, highly technical industry whose product is no longer considered optional. It’s such a necessity that today even areas blessed with copious natural snow install snowmaking systems to ensure consistency and consumer confidence. And the technology has made it possible for the sport to expand into regions Mother Nature never intended: Georgia, Alabama, Australia, Singapore, even the desert city of Dubai. Indeed, the powder that comes from clouds has been reduced to a bit player—at best a promotional tool, at worst a nuisance. “We love to have natural snow,” says Barry Tucker, vice president of mountain operations at Okemo Mountain, in Ludlow, Vermont, “but to have a major storm on a Friday night just kills your weekend business” because skiers can’t get to the resort.

Pierce’s invention earned him and his partners next to nothing. Not long after their initial collaboration with the Tropeanos, the trio sold out to the Emhart Manufacturing Company, a Farmington, Connecticut, hardware manufacturer. Emhart also failed to make the system work, and it in turn sold the rights to the Tropeanos, who had begun selling their own versions. They tweaked the Tey nozzle design while announcing to the world that they had accidentally discovered their process while experimenting with “cloud-forming equipment” to protect citrus crops. The story, admits Phil Tropeano, was a fiction created by his brother “to make it look like we didn’t steal the patent.” But he adds, “It was a simple thing that anyone could copy… . It was a process patent using compressed air and water, and it was a good patent for a while, but it was a simple thing. There was nothing that anyone couldn’t copy.”

Each year the brothers found some way to improve their system, from pre-cooling the compressed air to using different diameter pipes or designing a nozzle with an internal chamber in which air and water mixed before the frozen particles were shot out through a tube, the snow gun, which would become an industry mainstay. “As time went on, we got to makeit pretty simple to use, but itdid take time,” Tropeano says. Still, snowmaking was a tough sell at first, given the cost and the initial technical problems. Besides, Tropeano admits, “it didn’t make as good snow as natural.” Unlike the real thing, machine-made snow as often as not froze into a solid sheet of ice. At the end of the 1950s only 18 out of 104 ski areas in New England and New York had any snowmaking capacity at all.

But the Tropeanos persevered, and their aggressive salesmanship began to persuade ski-area operators, mostly in the Midwest and the southern Northeast, to install systems as insurance against fickle weather. At the same time, other inventors entered the game. In 1958 Alden W. Hanson of Michigan filed a patent for the fan snowmaker, a device that looked somewhat like a jet engine and used propeller blades instead of compressed air to disperse water droplets, thus saving on energy. A later variant, the Hedco snowmaker, used the spinning blades of the fan to atomize the water too.

The early systems were generally small and limited in their capacity, so they could cover only a few slopes at a time. They were also extremely labor-intensive, needing significant time and attention to get their water and air supplies “charged” and the guns in place, and then keep the air-and-water mixture right to obtain the consistency of snow desired. With many commercial systems complex and unreliable, operators did a lot of improvising, cutting pipe, installing valves, designing their own nozzles, and developing their own control systems.

In 1963 an avid skier named Ron Ratnik decided to give up a comfortable job as an engineer at General Motors to pursue a passion. With two partners, he raised $2.5 million and opened a resort at Bristol Mountain, in Canandaigua, New York. In just nine months the three cut trails, installed a chairlift, and put up a lodge. The next year Ratnik, realizing the advantages a reliable snowmaking system would give the area, designed and built his own system. “The early snowmaking systems were pretty primitive,” he explains. “The first snow I made was over the summer in a cold chamber.” To keep his water pipes from freezing, he buried his water lines five feet underground, with hydrants in galvanized culverts that he filled with cow manure as insulation against the cold. Soon he started manufacturing and selling his components and enlarging the capacities of his snow guns and hoses, and he now heads Ratnik Industries of Victor, New York, one of the world’s leading manufacturers of snowmaking systems and equipment.

The first top-to-bottom snowmaking system in New England was at Big Bromley, in Vermont, in the 1965–66 season. (Big Bromley needed it especially badly since its trails, unusually for the region, faced south.) Covering 70 percent of the mountain, Big Bromley’s system cost $750,000 and could pump 1,450 gallons of water and 9,140 cubic feet of air a minute, a huge increase over anything before it. (By contrast, today’s systems can pump as much as 12,000 gallons of water and 60,000 cubic feet or more of air a minute.) “Nobody thought you could cover a whole damn mountain with snowmaking,” the owner, Fred Pabst (a scion of the brewing family), boasted to a reporter. “Now they all want to come study how I do it. What they don’t know—in fact, what I don’t know—is whether this kind of expenditure can ever pay for itself.”

He soon got his answer. The season had typically started the day after Christmas or even late in January and run for as little as 30 days; now skiers could predictably enjoy the slopes from Thanksgiving to almost Easter. At Killington, Vermont, the owner, Preston Smith, committed to snowmaking after he and his staff spent Christmas Day in 1962 picking rocks off his slopes in hopes that the forecast snowstorm would materialize. After that his resort made it a point of pride (and savvy marketing) to be the first to open and the last to close in New England, making for a ski season that some years ran from late October to early May.

With snowmaking, New England areas could now cut long, wide runs like those found at Western ski resorts, which many skiers found preferable to the old narrow, tree-shaded trails that previously distinguished traditional New England areas. And skiers could now plan their vacations ahead of time, with little concern about conditions. This meant more resorts, which could book more lodging and add restaurants, shops, and other amenities. Skiing took off. The number of skiers rose from around 3 million in 1962 to nearly 10 million by the end of the 1970s.

“I remember visiting one resort when the phone rang,” Ratnik says. “The caller asked if the area had snowmaking. The guy said, ‘No, but—’ and the caller hung up. The guy didn’t even get a chance to say that the area had three feet of new snow.”

The pioneers—Pabst, Ratnik, the Tropeanos, Hanson, and others—figured out on their own the principles that would become the science of snowmaking. Under normal conditions, water freezes at 32 degrees Fahrenheit. But it’s not that simple. When the humidity is high, water may not freeze even at below 32. When it’s dry, water can freeze at temperatures above 32. This is because a droplet of water cools when part of it evaporates. The more humid and saturated the air, the slower the evaporation and cooling. Thus efficient snowmaking requires both low temperatures and dry air. Snowmakers learned to take the ambient air temperature (or “dry-bulb” temperature) and adjust it for humidity (“wet-bulb” temperature).

Another variable is how much exposure to the air the drop-lets from a snow gun have before reaching the ground. The greater the “hang time,” the better the chance they’ll have to freeze and so the greater the rate of crystallization. Thus, fixing snow guns to towers can increase a system’s efficiency. By the same token, using more compressed air makes for smaller droplets and greater hang time and thus drier, fluffier snow—but at steeper expense.

In snowmaking, as in nature, water vapor crystallizes around minute specks of dust or ice. If the water source doesn’t have enough naturally occurring impurities in it, snowmakers can add artificial “nucleators.” Snowmaking, Ratnik says, has always been a science, but “for a long time, if those who knew the science all got together, they could have fit inside a phone booth.”

It remains an art as well. A good snowmaker must consider numerous variables—temperature, humidity, wind, the type of snow required—in deciding exactly how to adjust a system. Few people understood this in 1981, when Scott Barthold, a former ski racer and Dartmouth engineering-school graduate, decided to specialize in snowmaking. He’s now the president of Sno.Matic Controls and Engineering, a New Hampshire firm that designs snowmaking systems and controls. “When I started,” he says, “a number of people had upgraded things to make it more into an industrial process, but there were a lot of older, just flung-together things.” Most snowmaking operators back then began by laying down a thick layer of ice to create a base that would withstand a thaw or a rainstorm. But it was hard to get anything else to stick to that icy base. New snow that fell on it, either natural or machine-made, simply got skied off or blew away, leaving just the base.

A handful of innovators, however, learned how to create a more congenial, softer base and preserve it too. Then, as more skiers went to the slopes, more wear and tear followed. Improved snowmaking and trail grooming kept pace. “Snowmaking is here to stay,” Preston Smith announced at Killington in 1974. He predicted that soon most ski-area operators would depend solely on machine-made snow and that skiers would demand it. He was right. Even in the West, ski areas began installing systems in the late seventies and early eighties. “The old model, where you could rely on a good year to let you ride out a bad one, no longer held,” Ratnik says. “The investments being put into resorts were too huge.” Today ski areas everywhere, from Utah to Switzerland, have large-scale snowmaking systems.

Trail-grooming technology makes sure that the money spent making snow isn’t lost when the snow is blown off by wind or skied off by crowds. High-tech grooming machines today can churn, grind, plow, and otherwise rehabilitate a snow surface that has been packed hard or scraped down by heavy traffic. Grooming, Barthold says, is “the other half of the equation.” As high-speed chairlifts have enabled ski areas to significantly reduce the time spent between runs, the increase in the number of skiers has made the challenge of maintaining decent snow cover that much more difficult. Newer equipment, including snowboards and shorter, tighter-turning skis, also tends to chew up trails more quickly than did that of the past.

Snowmaking does have its drawbacks. The most obvious is cost. New systems can run in the tens of millions of dollars to install and thousands of dollars a day to operate. At Sunday River, Maine, the electric bill to run the system costs $1,700 an hour. Newer technologies, including low-energy snow guns, and can reduce operating costs, but they have their own limitations in terms of production capacity and operating range. Snowmaking is generally the second-biggest expense at a ski area, after labor. As a result, the cost of skiing has risen considerably. The average cost of a daily lift ticket in 1962 was $3 (which would be about $20 today); nowadays you can expect to pay as much as $75 a day. Schoenknecht worried in 1969 that “a $15 lift ticket may not be out of line”; this would be equivalent to about $80 today.

By the late eighties the water needs of some ski areas (Killington, for example, uses as much as 470 million gallons a year) were drying up local streams, leading to direct confrontations with environmentalists and state conservation authorities. Many areas began building large reservoirs that could be filled during periods of high runoff and drawn on during the winter.

Today the big trend in snowmaking is automation. High-tech systems rely on computers to monitor conditions and control production, so as to maximize efficiency and uniformity. Manual systems, Richard Brown of York Snow explains, require too much time and labor. For a system with, say, 300 guns, 35 men might spend three or four hours a day trekking around the mountain, setting up the guns and adjusting each one for the particular conditions at its spot. Temperature, wind velocity, and trail conditions vary widely across a hill and can change quickly, requiring further adjustments. With an automatic system, a single operator at a computer can control the place, time, and quality of production, all of which can be preset to reduce guesswork and waste. He or she can monitor conditions such as water-flow rates, water temperature, airflow rates, and air pressure. Weather stations in each zone of a mountain relay information on the temperature, humidity, and wind direction, allowing for quick adjustments in changing conditions. Also, start-up and shutdown are faster, a critical advantage in places where the window of opportunity for making snow is narrow.

So far ski areas in Europe have led this transition. There 98 percent of installations are fully or partially automatic; in the United States, only 15 percent are. The reason, Brown says, is the economics of skiing in Europe. Labor laws prevent the use of seasonal labor in many countries, so automated systems eliminate year-round salaries. But as the reliability and versatility of such systems improve, American resorts will likely follow suit.

However, Ray Kennedy, the snowmaking systems manager at Okemo Mountain, in Vermont, isn’t so sure. “These guys are always coming around, trying to sell us something. My answer is always the same: I’ll take a decent snowmaker over a computer anytime.” Scooting up the mountain on a snowmobile, Kennedy zips through clouds of freshly made snow hissing from wands along the sides of trails. On occasion he stops and sticks out his arm, an age-old method for testing the quality of the snow. If the snow is too wet, it sticks to his sleeve. He makes sure it is blowing onto the trail. A sudden wind shift can leave most of the snow blowing into the trees. This, he says, is something a computer can’t tell you. He manages two crews of 10 to 12 people working 12-hour shifts. Most of them are from Australia or South Africa. At the end of the season they travel to the Southern Hemisphere, chasing winter.

Running at its peak, Okemo’s snowmaking system consumes 9,000 gallons of water and 37,000 cubic feet of compressed air per minute while burning 6,000 kilowatts of electricity. Allowing for the type of gun, the temperature, and the humidity, a typical trail takes 24 hours to be covered with enough snow to be skiable.

A number of indoor skiing facilities have opened around the world over the past decade, pushing the science of snowmaking into the realm of science fiction. The technology that surfaces these enclosed hills varies. In some cases the hill is simply a huge sloped ice rink that instead of being smoothed for skating is scraped to produce a soft, skiable surface. In others, giant air conditioners chill the building so that snow can be made in a more or less conventional manner. An Australian inventor has created a gel-like polymer that, when mixed with water, expands to 40 times its volume, making a “snowlike substance”—exactly how snowlike depends on your point of view. Its main intended use is in the film industry, but it can be mixed with regular snow for skiing, and the U.S. military is experimenting with it as a tool for “mobility denial.” Another company has created “cryogenic” snow, using water, compressed air, and liquid nitrogen to produce snow at temperatures of up to 120 degrees Fahrenheit. In some places, huge blocks of ice are ground, and then the flakes are blown through hoses onto the slope, a technique not unlike the one Schoenknecht used more than a half-century ago. This technique is favored when ambient temperatures are not cold enough to form snow.

Such processes, as Barthold says, are really novelties and are quite separate from the technologies used to manufacture snow across entire mountains. They are simply too expensive. In fact they are too expensive in some cases for the miniature hills they are expected to cover. As for the snow domes, the SSAWS skidome in a suburb of Tokyo opened in 1993 at a cost of $400 million to build and $40 million a year to run, and it closed in 2002, eight years before its operators projected that it would break even. Still, advocates of snow domes credit them with creating thousands of new skiers and snowboarders each year.

For do-it-yourselfers, there’s even now a home snowmaking system. Basically a variant of Tey’s original machine, the Backyard Blizzard consists of an air compressor and a water pump that hook up to a common garden hose. Made by HKD Snowmakers, of Natick, Massachusetts, it costs $2,400 and can make 50 cubic feet of snow an hour.

Everything, it seems, has come full circle. But despite all these advances, the one thing that man and snowmaking technology have not been able to duplicate is the true cloud-generated snowflake. For that, you’ll still have to rely on Mother Nature.

Tom LeCompte wrote “ Cinerama: Secret Weapon of the Cold War ” in the Fall 2005 issue.

We hope you enjoyed this essay.

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