Leon County, FL Environmental Rules: Grading & Drainage (2026)

Leon County treats topographic grade changes as development requiring a permit from Development Support & Environmental Management unless specifically exempt. The Land Development Code's environmental management provisions (Chapter 10, Article IV) classify slopes as natural features to be delineated and protected — significant grades are greater than 10% and less than 20%, and severe grades are greater than 20% — and these are addressed under the Table of Standards for the Protection of Natural Features (see § 10-4.202(a)(2)). If flood-zone grade changes are proposed, the applicant must show compliance with the restrictions in § 10-4.327(3); a drainage or conservation easement is required for the limits of the 100-year floodplain and any floodway as determined during the Natural Features Inventory. Drainage design is reviewed against the stormwater standards in § 10-4.303 and must demonstrate, through calculations and topographic maps, that anticipated rates of flow and volume increases can be handled downstream without causing adverse impacts to wetlands, watercourses, waterbodies, and stormwater conveyances. Applicants must provide a 2-foot contour map tracing the stormwater discharge path to a downstream receiving water body or watercourse with at least 40 times the site's storage volume or discharge rate.