When rain (and other types of precipitation like snow, sleet, or hail) falls to the ground, the surface it lands on plays a big part in what happens next. 

On natural surfaces like dirt or rocks, water will steadily soak into the ground, with native plants helping filter out debris and harmful substances. However, in instances where the surface does not allow water to soak through—such as brick, stone, or other paved surfaces—it will collect and move across the land toward the nearest waterway, picking up all sorts of pollutants along the way. This is called stormwater runoff.

In this case, pollution doesn’t just mean oil or trash. Excess fertilizer and pesticides from lawns, loose soil, or even dog poop can all end up in a nearby waterway.

With this activity guide, you can learn more about stormwater and how to reduce its impact on the environment. The guide also has instructions for building your own rain gauge and rain garden!

Download the What is Stormwater? Activity Guide using the link below.