Georgia Code Title 12. Conservation and Natural Resources § 12-5-237

(b)(1) No permit shall be required for a structure, shoreline engineering activity, or land alteration which exists as of July 1, 1979, provided that a permit must be obtained for any modification which will have a greater adverse effect on the sand-sharing system or for any addition to or extension of such shoreline engineering activity, structure, or land alteration; provided, further, that, if any structure, shoreline engineering activity, or land alteration is more than 80 percent destroyed by wind, water, or erosion as determined by an appraisal of the fair market value by a real estate appraiser certified pursuant to Chapter 39A of Title 43, a permit is required for reconstruction.

(2) No permit shall be required for any activity conducted pursuant to a letter of permission. At least 15 days prior to the commencement of any activity authorized pursuant to a letter of permission, the department shall provide public notice describing such activity and the location thereof; provided, however, that public notice shall not be required for any such activity that is necessary for public safety or the delivery of public services.