Understanding Tennessee’s New Industrial Stormwater Permit Requirements
As environmental regulations evolve, staying ahead of compliance requirements is critical for industrial operators. On July 1, 2025, the Tennessee Department of Environment and Conservation (TDEC) implemented a new version of its Multi-Sector General Permit (TMSP), which governs stormwater discharges from industrial activities. This update brings changes that will affect existing and new facilities alike, and now is the time to prepare.
Tennessee Launches New Stormwater Permit for Industrial Facilities
Effective July 1, 2025, the Tennessee Department of Environment and Conservation (TDEC) has issued the updated Tennessee Multi-Sector General Permit (TMSP), which governs stormwater discharges from industrial activities across the state. The permit will remain in effect through June 30, 2030.
Under federal regulations, stormwater discharges from certain industrial sectors must be covered by a National Pollutant Discharge Elimination System (NPDES) permit. The TMSP fulfills this requirement by mandating that facilities implement stormwater control measures (SCMs) and develop site-specific Stormwater Pollution Prevention Plans (SWPPPs). Facilities are urged to review the permit requirements carefully and ensure timely compliance.
Key Deadlines:
Existing facilities must submit a Notice of Intent (NOI) permit application by September 30, 2025.
New facilities must file an NOI at least 30 days before discharging stormwater.
TDEC encourages facilities to submit their SWPPP alongside the NOI. The SWPPP must outline how the facility will minimize pollutants in stormwater runoff through the design and implementation of SCMs.
Monitoring & Compliance Requirements:
Quarterly visual inspections of all outfalls
Annual comprehensive facility inspections
Annual stormwater sampling and analysis, if required by industry sector
Annual submission of Discharge Monitoring Reports (DMRs), if required by industry sector
What This Means for Your Facility
With the September deadline approaching, industrial facilities across Tennessee should take proactive steps to assess their compliance needs. Reviewing your current SWPPP, updating stormwater controls, and preparing the necessary documentation will not only ensure regulatory compliance but also help reduce environmental risks.
If you're unsure where to start, we’re here to help you interpret the new permit language and guide your next steps.