Septic services in Tennessee
In Tennessee, on-site wastewater is regulated by the Tennessee Department of Environment and Conservation (TDEC) through its Division of Water Resources under the Subsurface Sewage Disposal System (SSDS) Program. The governing rules live in TDEC Chapter 0400-48-01, which sets standards for soil evaluation, drainfield design, setbacks, and installer licensing, with statutory backing in Title 68, Chapter 221 of the Tennessee Code. Local TDEC environmental field offices (and a handful of delegated county health departments such as Knox, Hamilton, Davidson, Shelby, and Madison) handle day-to-day site evaluations, construction permits, and final inspections. Before any new system or major repair, a property owner must obtain a Septic System Construction Permit; once a licensed installer finishes the work, an Environmental Scientist inspects and issues a Certificate of Completion. Tennessee licenses both Conventional and Alternative SSDS installers plus septage pumpers, all renewable annually, and publishes a searchable Installers and Pumpers DataViewer the public can use to verify credentials by county. Roughly a third of Tennessee homes, about one million systems, rely on septic. The state's defining challenge is karst limestone across Middle and East Tennessee, where shallow bedrock and sinkholes can pipe untreated effluent straight into groundwater.