OK...
I for one, have been looking at thousands of acers of land ALL over the state of Georgia, for about 6 years!! I can tell you this it is very very hard to find a tract that will hold 12 to 15 surface acres of water. This is what I have found...
For 1 to 2 acre pond, very easy, these sites are every where.
For 3 to 5 acre pond site, gets a littel tough but still some what do-able.
For 6 to 7 acre lake site, tough but can be found if you do some searching.
For 8 to 10 acre lake site, very tough! they are very rare, unless you start running into 'wetlands' and thats a different issue all together.
Lakes that are bigger than 10-12 acres are usually built by public for parks and recreation.
Lake bigger than 25 acres would be VERY VERY expensive!! and nearly impossible to do without destroying wetlands.
Now, this is the case for North Georgia, in other words, above the Fall Line.
If you go below the fall line, and you then multipy these acrages by a factor of 2.5, i.e, for a particular tract of land that can hold 4 acres of water in North GA, can hold around 10 acres in South GA.
Now the further south you go, the flatter the land gets, hence you can back up water eaiser for more surface acerage.
Steave,
Have you looked at or studied any topo maps? I would bet that unless you dammed up a major creek system, that you are going to back up nearly 80 to 100 feet of water!! This is as deep as some parts of Lake Lanier and deeper than Lake Oconee.
To build a 100 acre lake in north Georgia one would really need to own about 1000 acres. Then would need to have about 2500 acres of a water shed drainage, that flattens out into a flat wet bottom. This mind you, would have wetlands associated with it, which has its own legal matters in its self. The project cost would be around $6,000 to $8,000 per surface acre to build so you would be looking some where between $600,000 to $800,000 in cost.
I recently bought a timber tract here in North Georgia as well. Where is your tract located? What county and town? Maybe I could meet you on your tract of land to see what you have???