Franklin, TN Environmental Rules: Stormwater Management (2026)

Franklin's stormwater program is built on three layers: federal (the EPA NPDES Phase II MS4 framework under 40 CFR 122.34), state (TDEC's NPDES MS4 General Permit TNS075523 administered under the Tennessee Water Quality Control Act, T.C.A. 69-3-101 et seq., and Rule 0400-40-10), and local (Title 23 of the Franklin Municipal Code, most recently amended by Ordinance 2025-24 and originally restructured by Ordinance 2017-41). Franklin received its TDEC Qualified Local Program designation effective August 1, 2017, which authorizes the City to issue Notices of Coverage under the TDEC Construction General Permit (CGP) TNR100000 directly to operators of land-disturbing activities inside the corporate limits, in lieu of TDEC processing every NOI. Franklin's MS4 program addresses the six federally required Minimum Control Measures: public education and outreach, public involvement, illicit discharge detection and elimination (IDDE), construction site runoff control, post-construction stormwater management for new and redeveloped sites, and pollution prevention and good housekeeping for municipal operations. The MS4 program is unusually consequential because the entire city drains to the Harpeth River, a watershed that has been listed by American Rivers as one of the most endangered rivers in the U.S. and that is designated under the Tennessee Scenic Rivers Act (T.C.A. 11-13-101 et seq.) on its lower segment in Davidson County. Title 23 prohibits non-stormwater discharges to the MS4 (except for permitted discharges and firefighting flows), requires riparian buffers along regulated waterways, requires green infrastructure for development and redevelopment of one acre or more under Section 23-101 (effective January 1, 2014), and authorizes the Stormwater Coordinator to inspect, sample, and require corrective action. Report illicit discharges, oil sheens, sediment, or sewage in the storm drain system to stormwater@franklintn.gov or (615) 791-3218.