Since I am often asked about stream buffers and how they relate to land development and real estate valuations I thought I would take a few minutes to write a story about this subject. The first thing one needs to know when addressing a stream buffer is what is the definition of a “stream”. As far as most stream protection ordinances go it is defined just like you would think it would be…a stream is a stream… Right? well in an effort to be accurate in this story even I am having second thoughts on my own definition as it relates to Fulton Counties Stream Buffer ordinance. The important thing is if it is a USGS Blueline Stream then it is definitely going to be considered a “stream” (or at least in Cobb, Fulton, Dekalb and Gwinnett counties).
Here is Fulton Counties Definition:
Stream - means beginning at 1) the location of a spring, seep, or groundwater outflow that sustains flow; or 2) a point in the channel with a drainage area of 25 acres or more; or 3) where evidence indicates the presence of a stream in a drainage area of other than 25 acres, the Fulton County Department of Environment and Community Development may require field studies to verify the existence of a stream.
USGS Blueline Stream – means a perennial stream that is depicted on a United States Geological Survey (USGS) 7.5-minute quadrangle map (scale 1:24,000) with a solid blue line.
Here is a quick and dirty stream buffer analysis I just did the other day:

Using Fulton Counties GIS map I have taken a property that on the surface looks like it could be developed, but after overlaying 75 foot radius rings it becomes clear just how much of the land is unusable. It is possible to get a variance, but this of course should be obtained before closing on a piece of property such as this for development because of the risks of not being granted the variance.
So the key being able to identify a “stream” and also being able to identify the correct buffer based on the county or city jurisdiction the subject property is in.
While I always recommend reading the full text of any ordinance I might be having to comply with, here is a brief overview of a few counties here in Atlanta:
Cobb County: Minimum fifty-foot wide buffers are now required for all streams, increasing to as much as 200 feet depending on the contributing drainage area. Click Here for Cobb County Ordinance
Fulton County: North Fulton County shall require a minimum 50-foot undisturbed buffer on each side of the stream as measured from the top of bank. Streams in all watersheds within unincorporated South Fulton County shall require a minimum 75-foot undisturbed buffer on each side of the stream as measured from the top of bank. An additional 25-foot setback shall be maintained adjacent to the undisturbed buffer in which all impervious surfaces shall be prohibited.
Click Here for the Full ARTICLE VII FULTON COUNTY STREAM BUFFER PROTECTION ORDINANCE
Fulton_County_Stream_Buffer_Variance_Procedures.html
Gwinnett County: The ordinance creates a 75’ buffer along both sides of a stream. There is a 50’ undisturbed area with an additional 25’ setback on impervious surfaces measured from the top of each stream bank. However Gwinnett’s has a few different rules so check them out by clicking here
Dekalb County: 50-foot undisturbed buffer and an additional 25-foot setback shall be maintained adjacent to the undisturbed buffer

