Stormwater Basics

What is stormwater runoff?

When it rains, some of the rainwater soaks into the soil, and part of it flows over the ground and directly into creeks, streams or rivers. This water that runs off land surfaces is called runoff, or stormwater runoff.

What is a watershed?

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 happens to a watershed can affect what happens to our streams, rivers and lakes. 

Why be concerned about stormwater?

Stormwater runoff occurs naturally, but as development and imperviousness 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 picks up pollutants such as 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 leading to water quality violations.

Because metro north Georgia region uses its rivers and lakes for recreation and as its primary source of drinking water, stormwater and watershed protection is something that everyone needs to be aware of.  

How do we address the negative impacts of stormwater runoff?

There are a number of ways to address the impacts of stormwater runoff.  These include requiring post-construction structural stormwater controls for both runoff quantity and quality on all new development and redevelopment projects; encouraging better site design to reduce imperviousness and leave more land as greenspace; promoting pollution prevention practices to help keep contaminants out of stormwater; addressing illicit discharge and illegal connections to storm sewer systems; and providing for stream buffer protection and effective floodplain management.