University of Wisconsin - Extension

It seems like every year we get hit with a rainy season when the weather gives everyone a chance to sit and wait, while it rains, and rains and rains.

What happens to all that water? The swollen rivers and streams show us where much of it goes. But did you ever consider what happens to the water en-route?

"Stormwater starts its journey to our lakes and rivers when it washes across the surface of the land, picking up residue along the way," explains Suzanne Wade, University of Wisconsin-Extension Rock River Basin educator. "The most harmful kinds of material that gets picked up includes pesticides, oil, gasoline and heavy metals. Heavier rains can also destroy croplands, washing tons of soil into the nearest body of water."

Water washing off streets may enter a road ditch, or it may drain into a storm sewer. We know that ditches in front of our homes and in the farm fields funnel water toward waterways. But did you know that storm sewers, like road ditches, carry rain and melting snow to the nearest body of water? A common misconception about storm sewers is that they convey water directly to a wastewater treatment plant. But this is not the case.

"No matter if stormwater empties to a ditch, soaks into the ground or drains into a storm sewer, it's going to end up in our rivers, lakes and drinking water," adds Wade. "This is true whether its relatively clean rainwater or stormwater mixed with gasoline, oil, antifreeze or fertilizer."

Chemicals and nutrients eventually enter lakes, streams and groundwater, becoming pollutants that ruin natural aesthetics, kill fish and contaminate drinking water supplies, Wade adds. "Water that soaks into the ground may travel downward hundreds of feet before reaching the water table. Sometimes the soil can filter out or break down contaminants. Sometimes it cannot. Purified or not, this groundwater feeds our lakes and rivers."

The first step in keeping our water supplies clean is to stop and consider the land and what goes on it. Then ask yourself which lake or river is nearest you. Next take the following steps to help stem the flow of contaminants that could be washing into the nearest lake or river.

• Don't allow grass or soil to wash off your property to ditches or gutters.
• Sweep fertilizer, grass and soil off walks and driveways.
• Reduce winter salt on walks and drives.
• Don't dump gas, oil, antifreeze, etc., on the ground or in storm sewers.
• Clean up after your pets. Pet waste adds bacteria and unwanted nutrients to waterways.
• Redirect downspouts away from paved areas toward vegetated areas.