04/18/2013 15:08

            It rained. Then it rained some more. Water ran from watersheds, ran off over the surface into streams and rivers, more than the waterways could drain, and the water spilled onto floodplains. In the city it ran down gutters into storm drains and into the river. In the country it followed roadside ditches into nearby waterways. When the gutters and ditches had more than they could drain, it covered roadways.  What infiltrated the ground raised the water table allowing the water to find new ways into our basements.

            We see the water vapor in the air when it forms droplets and gathers into clouds. We can see each raindrop as it drops onto a wet surface, into a puddle, or onto our windows. We can feel raindrops on our faces and hear it on our jackets, umbrellas, and raincoats and on the roof.

            “A nice approximation of a 1 inch rain in 4 hours is one raindrop per square inch per second for the entire 4 hours,” according to Joe Spence of the Galesburg USDA-NRCS Field Office. Spence used cubic inches based on 3 millimeters as an average size raindrop to conclude there would be 2,002,907 drops per 1 inch rain per square foot.

            Spence suggests that we use drops of water to help us understand how much water we can conserve by fixing a leaky sink faucet. If a faucet drips 1 drop every second, then in a 24 hour period, the wasted water is the equivalent of a 6 inch rain.

            Conservation practices protect acres of soil from all these raindrops.  On bare soil, each raindrop makes a mini-explosion.  (To see the effect of a raindrop on bare soil, place a small amount of soil on white paper and observe as you drop water on the soil one drop at a time.) The impact of each raindrop loosens the finest topsoil particles. When soil is loosened, the topsoil and its nutrients get moved by the water and carried away in runoff to streams, rivers, and water bodies. These soil particles and nutrients, which are commonly referred to as sediment, can clog our waterways and damage water quality harming the aquatic life of waterways.

            While you watch the rain drops fall, consider that water molecules are not being created or destroyed, just recycled in the global system we know as the water (hydrologic) cycle. All the water molecules we have were here when earth began. Evaporation purifies the water to provide us with freshwater on which all land and freshwater life depends – 97 percent of earth’s water is salt water. It is up to us to keep our freshwater supply pure as it falls through the air, and over the surface and under the surface of the watersheds around us.


Della Moen, Earth Team Volunteer, NRCS/Stephenson Soil and Water Conservation District, an equal opportunity provider and employer, 04/17/13 (for publication on 04/20/13 in the Journal-Standard, Freeport, Illinois). Della can be reached at info@stephensonswcd.org