Monday, September 22, 2008

Snowmaking and Water Use


Here is a question we received from someone after they read our blog asking for questions pertaining to the environmental impact associated with snowmaking.

Q: If you make snow in your backyard (or at a ski resort) is the water wasted?

A: This is a common question we get from people who have a concern with the environment. Contrary to popular belief, snowmaking doesn't waste large amounts of water. In fact a study that was conducted by a major snowmaking company (for ski resorts), indicates that more than 85% of the water used for snowmaking at ski resorts is returned safely. In home snowmaking the percentage of returned water is greater, around 95% or more.

When a ski resort makes snow they typically draw water from a retention pond or large reservoir situated at or near the base of the mountain. The purpose of this is too cool the water and to recollect the water in the spring and summer when the snow melts. As you can imagine snowmaking uses a lot of water, and if a ski resort has to buy water each year it could get very expensive. If they can reuse the water they made snow with the previous year, not only do they help the environment, but they save money on water. The water is recollected in the reservoir as the snow melts and the water runs either directly down the mountain into the reservoir or the water flows into a piping network which ultimately returns the water to the reservoir.

If not all the water returns to the reservoir, most of it seeps into the ground on the mountain and trickles down into the water table. Some of the water evaporates when snow is being made or as the snow is melting. The evaporated water is then returned to the atmosphere.

Although snowmaking returns most of the water, you will still find some resorts have limits on how much water they can consume for snowmaking, where they can draw water from, and how long they can make snow. If a ski area doesn't have a retention pond, they could very easily drain a creek or small river of all the water. This is why the Government steps in to prevent this from happening. A good example is out in Colorado. Most ski resorts are only able to make snow in the beginning of the season. They get permission from the US Forestry Service to use water from September to the end of the year for snowmaking. After the New Year, they cannot make snow until September. This is fine for Colorado because they typically get enough natural snow to cover the entire mountain with snow for the season.

The reason why snowmaking at home returns more water is because it almost all seeps into the ground when the snow melts and finds it's way to the water table. This of course doesn't take into consideration the amount that evaporated during snowmaking or that was evaporated into the atmosphere as the snow melted. When the spring comes, you will notice your grass is much greener where you made snow compared to the rest of your lawn. This is because the water seeped down to enter the water table after the snow melted.

We hope this helps you understand how making snow in your backyard and at ski resorts doesn't waste all the water that was used to make snow.


www.snowstormsnowmaking.com