During this time of year, it is beautiful to look from the valley up and out to the mountains and see them covered in white. As desert dwellers, we find comfort knowing that the snow in the mountains is the source of our water. The snow that melts off each spring provides essential runoff to streams and reservoirs, while snow in the valley melts and recharges ground-water aquifers.
Did you know that the snowpack is carefully monitored and used for water predictions by the U.S. Department of Agriculture’s Natural Resources Conservation Service? The NRCS provides snowpack data and streamflow forecasts to help with water supply management, flood control, recreation, climate modeling, and conservation planning.
River forecasting methods use “snow water equivalent,” temperature, and sunshine information to estimate how snow melt will flow into rivers. Snow water equivalent is the depth of water that would cover the ground if the snow cover was in a liquid state. It is also sometimes referred to as the water content.
The water content of snow can vary greatly. Heavy, wet snow has a very high water content. Four to five inches of wet snow may contain about one inch of water. Dry, powdery snow has a low water content, and it may take upwards of 20 inches of dry snow to equal one inch of water.
The snowpack that accumulates each year in the mountains is a significant and vital part of the hydrologic (water) cycle. How much water does snow contribute? It is hard to say exactly, because there are many variables to consider, but the general rule is that 1 inch of snow, on 1 acre of ground (660 feet by 66 feet), about a football field minus the end zones, is equivalent to 2,715 gallons of water.
To help put this into perspective, if the Ruby Mountain Wilderness is about 90,000 acres, with only one inch of snow covering the surface, there would be about 2.4 million gallons of water when melted!
The water cycle consists of precipitation, evaporation, condensation, and collection. Therefore, not all of the snowpack melts into flowing water. Some is lost to evaporation.
Snowpack impacts humans, animals, and plants. Plant growth is slowed during years of drought, due to the impact on soil moisture. To overcome this consistent environmental hardship, typically, plants native to Nevada have long, deep tap roots and shallow lateral roots so that growth cycles can be completed, regardless of the annual snowpack. Animals also have adaptations to overcome low snowpack years. From hunting and foraging at night to avoid the desiccation (drying) due to the sunrays, to obtaining enough water from food, desert animals are naturally prepared to survive.
According to the NRCS, the storms of February built up the snowpack in eastern Nevada quite nice and the snowpack ranges between 80 and 106%. Get outside and enjoy the warming temperatures, while appreciating the water held in your local snowpack, it is good for humans everywhere.