Drought conditions have affected much of the country this summer, leading to low water levels and water restrictions. The drought has had a serious effect on farmers, but is also threatening ski resorts dependent on high water levels for snowmaking. A few soaking rains this fall will help Mid-Atlantic resorts reclaim water supplies, but in Colorado, where skiing is one of the main industries, more drastic measures are being taken.

Mid-Atlantic resorts live and die by snowmaking alone, but resorts in Colorado have historically relied on Mother Nature to blanket the slopes with snow. During the winter of 1977-78, Mother Nature decided to take the year off. A dearth of snow obliterated the ski season; many resorts were unable to open. After that season, Colorado resorts began investing in snowmaking systems.

Snowmaking is generally used early in the season at Colorado resorts, allowing the resorts to claim early opening dates and to lay a base on popular trails. Most resorts in Colorado only cover a small number of trails with snowmaking, but given the size of these resorts, that equates to many acres of terrain. This snowmaking requires water -; lots of water. In fact, the National Ski Areas Association estimates that snowmaking consumes over 100 gallons of water for every skier visit.

Covering a 10-by-10 foot area of ground with 6 inches of snow requires over 30,000 gallons of water. That water has to come from somewhere, and the drought of 2002 has decreased water supplies.

Without snow, the ski tourism industry in Colorado crumbles. Even if Mother Nature cooperates and delivers plenty of natural snow, snowmaking helps expand the season, contributing to each resort’s bottom line. For this reason, resorts have taken step over the years to ensure an adequate water supply, even during times of drought.

Colorado ski areas have aggressively obtained senior water rights over the years. This means that a resort is first in line to draw water from water sources -; often with a higher priority than other industries such as agriculture.

But water sources are low, so being first in line might not mean much.

Resorts are resorting to other measures, such as cloud seeding, to try and increase water supplies. Cloud seeding, although controversial, has been in practice for many years. During this fall and next spring, Colorado plans to double its cloud seeding efforts in order to boost snowpack levels and reduce drought conditions.

The concept behind cloud seeding is to “shake” the precipitation out of clouds as they pass by.

Every cloud has moisture in it, but the tiny, supercooled droplets in winter clouds won’t fall to earth unless they have something to bind to. Cloud seeding provides that binding agent in the form of silver iodide particles. Silver iodide particles are emitted into the clouds, either through airplanes or ground-based generators, and the water freezes onto the silver iodide particles, snowballing until it’s heavy enough to fall to the ground. Depending on the cloud type, liquid nitrogen, dry ice, or sodium chloride is sometimes used during seeding.

Thirty-four generators are already in operation near Vail, pumping silver iodide crystals into passing clouds.

Not everyone is a believer in cloud seeding. The effectiveness of seeding is often questioned; at best, seeding can only squeeze up to 20 percent additional precipitation from storm clouds. Some have questioned the environmental impact of the silver iodide crystals, although experts believe the amount used is too small to damage the environment.

Despite the debate, ski areas, towns, and counties in Colorado are contributing to an increase in seeding, as they look with concern to the low water levels and the approaching ski season. Careful planning and some high-tech countermeasures should ensure that the winter of 1977-78 isn’t repeated.