When it rains, water washes over roofs, streets, driveways, sidewalks, parking lots, and other land surfaces. Along the way, it can pick up a variety of pollutants, such as oil, pesticides, metals, chemicals, and soil. This polluted stormwater drains into subdivision storm systems and local ditches, which all eventually discharge into our rivers and streams. The pollutants can endanger the quality of our waterways, making them unhealthy for people, fish, and wildlife.

To help prevent these pollutants from reaching our streams we can work to keep rain where it falls and reduce new and existing impervious surface.  There are methods that encourage water to soak into the ground instead of installing pipes in the ground to quickly move all the water away. This will likely become more and more important as the region will start to face water shortages due to more consumption than supply (since we are not using practices to soak the water back into the ground to recharge our aquifers).  Click here for more information on a groundwater supply study in northeastern Illinois. 

We also need to stop pollution at its source and to keep stormwater clean, and thus our streams and rivers. There are a variety of land management activities that can help us achieve both of these things, they are referred to as stormwater Best Management Practices or BMPs.  BMPs can range from education programs like encouraging people to reduce their fertilizer or road salt use to the use of rain gardens or bioswales to filter stormwater coming off a parking lot to an oil and grit separator in a manhole at a gas station or a parking lot.  Everyone has a role in helping to keep stormwater clean.  Follow the links below to learn more about local programs dealing with stormwater issues.

 

 

DEFINITION

Impervious surface - Impervious surfaces are mainly constructed surfaces - rooftops, sidewalks, roads, and parking lots - covered by impenetrable materials such as asphalt, concrete, brick, and stone. These materials seal surfaces, repel water and prevent precipitation and meltwater from infiltrating soils. Soils compacted by urban development are also highly impervious.