It is the middle of winter and most likely water pollution, droughts, and groundwater levels are not things that you are thinking about right now. For most people these things tend to be more “warm weather” topics…but should they be?

Chances are there is some snow piled up somewhere in your yard or on your street right now, but it will not be there forever. As the snow melts it is going to end up in local rivers and streams, and also seep into the ground to become part of the groundwater supply. 

Just as rain runs off to other locations, so does snow, although because of the form that it is in, it may not be as obvious. For example, ten inches of snow when melted is equal to one inch of rain. So while the initial quantity of water during a snowfall is not as great as in a rain event, it can definitely add up.

This period of water recharge is important to assure adequate ground and surface water supplies not only now, but also in the coming summer months. Because it is cold in winter and there is less heat from the sun, there is less natural evaporation of water in wintertime, so more stays in ground and surface reservoirs.

Often when there is a milder winter with less snowfall, there is also a greater chance of drought conditions the following summer, as there is less snowmelt to be a source of water recharge. 

Looking at another angle in contrast to drought, many times late winter and spring brings episodes of flooding. Snow is melting and rain is falling at the same time causing ground and surface water to become overloaded with moisture.

The water is not able to sink into the ground because it is already saturated with water from snowmelt, and ends up running off into rivers and streams causing flash flooding.

A final consideration from a water quality standpoint, is that just like runoff from a rain storm, snowmelt can also carry pollutants to ground and surface water.  Anything that is put on the ground – oil, paint, chemicals, garbage – are termed non-point source pollutants and can be carried to rivers, streams or groundwater when the snow melts.

Just because something is buried under the snow, doesn’t mean that it disappears.

So the next time you have to shovel several inches of snow…think of it as a fluffy, white way of recharging our groundwater resources!

(Written By: Susan Boser, Water Resources Educator, Penn State Extension, Beaver County and reprinted from Penn State Extension's Watershed Wind newsletter.)

1/28/2013