Rainfall that does not soak into the ground, but instead flows over the land into creeks, streams, rivers or lakes is called runoff, stormwater runoff, or just stormwater.
A watershed is all the land area that drains to a given body of water. Every stream, river and lake has a watershed. Everything that takes place within a watershed can affect what happens to our streams, rivers and lakes.
Stormwater runoff occurs naturally, but as development and the amount of impervious surfaces such as rooftops, roads and parking lots increase in a watershed, the natural capacity of the soil and vegetation to infiltrate and take up rainfall decreases, and more rainfall becomes stormwater runoff. This can produce negative impacts such as streambank erosion and flooding.
In addition, stormwater runoff can easily pick up pollutants such as dirt, oil and grease, chemicals, nutrients, metals, and bacteria as it runs off the land and carries them to the nearest river or stream. This can result in water quality impairments which can affect human uses as well as aquatic life.
Because rivers and lakes are the primary source of drinking water in north Georgia, stormwater and watershed protection is something that everyone needs to be aware of.
There are a number of ways to address the impacts of stormwater runoff. These include: