Are snow cannons environmentally friendly?

European resorts have experienced a decrease in precipitation (rainfall) over the past five years which in turn has led to some resorts having to stringently control their water supply in order to conserve supplies. After the unseasonably warm temperatures and lack of early season snow during the winter of 2007, global warming has been at the forefront of winter sports enthusiasts’ minds. To counter this very real climate change, (a 4 degree temperature rise is anticipated by the end of the century) ski resorts are turning to artificial snow manufacture.

Snow canons are becoming increasingly commonplace in France, today 15% of French ski areas are covered by the machines and they are no longer confined to low lying areas. Tignes has equipped the bottom of the runs on the Grande Motte glacier with snow making equipment at 3000 meters and Val d’Isere will do the same next year on the Glacier du Pisaillas to preserve summer skiing. Millions of euros are invested in artificial snow manufacture every year, but the investment comes at a high cost to the environment.

It seems illogical to combat global warning, widely agreed to be created by the burning of fossil fuels with yet more energy outlay. In some resorts, such as l'Alpe d'Huez, snow making now consumes more power over an average season than the entire lift system. Furthermore, the machines constitute a visual blot on the landscape and contribute hugely to noise pollution. A single snow canon emits between 60 to 80 decibels, the equivalent of heavy traffic, which disturbs mountain wildlife.

Snow cannons spray water at great pressure into sufficiently cold air which then falls as snow on the ground and any long-term environmental impact of this at present is uncertain. We do know that artificial snow is much denser than natural snow and it takes a meter cubed of water to make two meters cubed of snow. This artifically created snow has an effect on the vegetation and melts much later than natural snow.

We do however understand that the manufacture of artificial snow is costly in terms of energy and quantities of water required. It is estimated that snowmaking in France uses as much water as a town with 170,000 inhabitants. Everyone knows that water freezes at 0C but the rainwater found in reservoirs for snow making has to be cooled to around -7 to -9C before it will freeze and make snow. If it is necessary to make snow at warmer temperatures, agents such as Snomax™ are added. Snomax is a protein which provides a nucleate for ice crystals enabling freezing at temperatures around -3C. York International says that Snomax is completely safe but extensive studies have not been carried out to determine the overall effects of such additives on the environment. Despite the construction of reservoirs, snow-making uses vast quantities of water with consequences on a region’s water courses and aquatic wildlife.

More worrying is the natural erosion caused by the increase in melt water which runs back down the mountain in the Spring. There is also a suggestion that chemical additives used in its production affect the natural vegetation. As melt water comes off the slopes, chemicals used in the production of snow potentially find their way into rivers that supply drinking water for the resort.

Ski Press World in 2005 reported that low lying resorts such as Les Gets (1172m) were spending up to €300,000 searching for additional water supplies in an effort to meet an increase in resort demands as resort expansion continues. In response to their use of snow cannons, Les Gets stressed: 'the manufacture of artificial snow did not have any impact on the water supplies', further commenting that their '...snow cannons principally use water supplies which are unsuitable for drinking water.' Whether the same can be said for all other resorts is a different matter! In Val d’Isere a 36,000 square metre reservoir has been built on the Iseran sector to supply water for the snow cannons that will boost the summer skiing available on the Pissaillas Glacier. The STVI Lift company in Val d’Isere are committed to employing summer skiing possibilities with a minimum of consequences for the surrounding environment and its ecology.

Finally, artificial snow is currently seen as the saviour of some European ski resorts however given that the vast majority of canons require low temperatures to operate, reliance on them in the warmer winters of the future seems misguided. Since the long-term answer to the snow question has yet to be found, the debate between environmentalists and the ski industry looks set to continue well into the future.