Snow-Fence Experiments in Alpine Areas

Abstract

Snow fences built up-wind of natural snowdrifts at four alpine sites in the Colorado Rocky Mountains changed snow accumulation appreciably. The 3 m tall fences increased the amount of snow at three sites but decreased it at the fourth. At two of the three sites where snow was increased, there was no change in melt rate, so the additional snow prolonged the melt period 1–3 weeks. Fences most successfully augmented natural snow accumulation at sites with level or gently sloping terrain down-wind from the accumulation site. Between 15 and 30 m of fence was needed to produce an extra 1000 m³ of water equivalent in the snowfields at the beginning of the melt season. Fences of the type described here, if properly located, are a means of increasing summer stream flow from alpine areas.