Stormwater Management

Last modified Thursday, June 19, 2008 15:55

The Stormwater Runoff Problem

After it rains, some of the water runs off the land and is called stormwater runoff.  This stormwater flows downhill to the nearest storm drain, stream, river or lake.

In an undeveloped watershed, most of the rain is absorbed into the soil and taken up by vegetation, with only a small amount of runoff occurring.  As a watershed is developed, impervious surfaces such as buildings, parking lots and roadways prevent rainfall from infiltrating the ground.  This results in increased stormwater runoff which can cause flooding and streambank erosion. 

In addition, stormwater runoff picks up a number of pollutants as it flows off of rooftops, lawns, streets and parking lots.  These contaminants include sediment (dirt), leaves, grass clippings, fertilizers and pesticides, oil and grease, litter, heavy metals and animal waste.  All of these can cause water quality problems in the receiving water body.

Addressing Stormwater Problems

Communities in the Atlanta region are addressing these issues through watershed and stormwater management. This involves a number of programmatic activities designed to mitigate the impact of stormwater runoff problems including requirements for new development projects, effective erosion and sedimentation control, floodplain management, pollution prevention, illicit discharge elimination and stormwater system inspection and maintenance.

Stormwater management also includes strategies to protect drinking water supplies, address water quality violations [link to Cleaner Streams], and improve conditions in impaired watersheds. The Metropolitan North Georgia Water Planning District has prepared a District-wide Watershed Management Plan which outlines the requirements for local governments in the Atlanta region for watershed management.