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Stormwater Permitting


Robert Karesh
Statewide Stormwater Coordinator
312 Rosa L. Parks Avenue, 11th Floor
Nashville, Tennessee 37243

Storm Water Permitting

Over the past 30 years, EPA and state water quality agencies have realized the great impact that rain water runoff has on surface waters - streams, rivers, lakes, estuary and ocean waters. Rain water falling on industries, urban areas and construction activities can become contaminated with sediments, suspended solids, nutrients phosphorous and nitrogen, metals, pesticides, organic material and floating trash. These pollutants are then carried into the surface waters. Unlike sanitary wastewater and industrial wastewater, most stormwater is not treated prior to entering streams. Pollution of stormwater runoff must be prevented at the source.

Federal, state and local governments have passed law and regulations to address the problem of polluted runoff. Phase I EPA stormwater regulations initiated a national stormwater permitting program in 1990, that applied to industrial activities, to construction sites of five acres or more and to urban runoff from larger cities. Phase II regulations in 1999 address additional urbanized areas, certain cities with population over 10,000, and construction activities of one to five acres.

The Tennessee Department of Environment and Conservation, Division of Water Resources implements the EPA Phase I and Phase II regulations in Tennessee.

Phase I MS4s

In response to the 1987 Amendments to the Clean Water Act (CWA), the U.S. Environmental Protection Agency (EPA) developed Phase I of the NPDES Stormwater Program in 1990. Under Phase I, EPA required NPDES permit coverage for stormwater discharges from:

"Medium" and "large" municipal separate storm sewer systems (MS4s) located in incorporated places or counties with populations of 100,000 or more

Eleven categories of industrial activity, one of which is construction activity that disturbs one or more acres of land.

This page contains information related to MS4s.

EPA's Stormwater Website

EPA's Phase I Web Page

Phase I MS4s in Tennessee:

Knoxville: TNS068055
City of Knoxville’s Stormwater Web Page

Nashville: TNS068047
City of Nashville’s Stormwater Web Page

Memphis: TNS068276
City of Memphis’s Stormwater Web Page

Chattanooga: TNS068063
City of Chattanooga’s Stormwater Web Page

Tennessee Department of Transportation (TDOT) Municipal Separate Storm Sewer System (MS4)
Permit Number TNS077585

Phase II MS4s

The EPA phase II final rule requires NPDES permit coverage for stormwater discharges from certain small municipal separate storm sewer systems (MS4s). In Tennessee, the Phase II program affect about 85 cities and counties by requiring them to obtain coverage under a stormwater discharge permit and to implement a set of programs to manage the quality of stormwater runoff from the storm sewer systems.

Note that as of March 10, 2003, construction activities of one acre or more must be permitted. This includes clearing, grading or excavation that results in an area of disturbance of one or more acres, and activities that result in the disturbance of less than one acre if it is part of a larger common plan of development or sale. This rule applies to construction activities begun before March 10, 2003, if one or more acres will be disturbed on or after March 10, 2003.

For approximately ten years, publicly owned sewage treatment works (POTWs) have been exempt from stormwater runoff permitting. That exemption expires on March 10, 2003. More information regarding this exemption.

The EPA rule also revised the "no exposure" exclusion for industrial facilities regulated under Phase I, and ends an exemption from stormwater permit requirement for municipally-owned or operated industries, such as wastewater treatment plants, landfills, transportation maintenance facilities.

Tennessee issued a small MS4 general permit on August 31, 2010, effective on October 1, 2010. If the division designates your municipality as a Phase II MS4, the MS4 is required to submit a NOI (below) to the division at the appropriate EFO within 180 days of notice. MS4s previously permitted must submit an NOI within 90 days of the effective date of this permit.

2010 Final Permit
Phase II MS4 Notice of Intent (CN-1295)
2010 Notice of Determination
2010 Rationale Sheet
Small MS4 Annual Report Form (CN-1291)

Tennessee-Specific Information

Current List of MS4s in Tennessee

To promote greater transparency, accountability and broader access to public information, the department makes a Water Resources Permits Data Viewer available to the public. This data viewer pulls information from the same consolidated database that TDEC regulatory staff uses to keep track of permit activity and status.

WPC Permits Data Viewer

Compliance Resources

University of Tennessee MTAS

Designed to provide permittees information on Best Management Practices for each of the six minimum controls required in the Phase II permit.

TN Water Resources Research Center

The Tennessee Water Resources Research Center (TN WRRC) is a federally designated state research institute supported in part by the U.S. Geological Survey. The Center serves as a primary link among water-resource experts in academia, government, and the private sector, and the diversity of its staff in terms of background and expertise enhances flexibility and positions the Center to establish productive partnerships. TN WRRC is housed within the Institute for a Secure and Sustainable Environment (ISSE) at the University of Tennessee Knoxville.

EPA’s National Menu of Best Management Practices for Phase II MS4s

Intended to provide guidance to regulated small MS4s as to the types of practices they could use to develop and implement their stormwater management programs

Stormwater Manager's Resource Center

Designed specifically for stormwater practitioners, local government officials; technical assistance on stormwater management issues; has fact sheets, slide shows, example ordinances; claims to be "everything you need to know about stormwater in a single site."

EPA Model Ordinances to Protect Local Resources

Various, example ordinances for Aquatic Buffers, Illicit Discharges, Erosion and Sediment Control, Post Construction Controls, etc.

STORMWATER - The Journal for Surface Water Quality Professionals

A magazine of interest to persons managing stormwater. Of ten engineers and scientists on the editorial board, two are local officials.

Center for Watershed Protection: Stormwater Management

The Center for Watershed Protection works to protect, restore, and enhance streams, rivers, lakes, wetlands, and bays. The Center creates viable solutions and partnerships for responsible land and water management and offers FREE downloads of Center resources on stormwater management.

Tennessee Stormwater Association (TNSA)

TNSA is a not-for-profit statewide Association developed by MS4s with the assistance of TDEC and UT-MTAS to assist local government entities in their efforts to comply with State and Federal clean water laws and Stormwater Regulations.

Nonpoint Source (NPS) Outreach Toolbox

The Nonpoint Source Outreach Toolbox is intended for use by state and local agencies and other organizations interested in educating the public on nonpoint source pollution or stormwater runoff. The toolbox contains a variety of resources to help develop an effective and targeted outreach campaign.


Stormwater Discharge Permit for Municipal Separate Storm Sewer Systems (MS4)
Large MS4s $10,380
Medium MS4s $6,920
Small MS4s $3,460

Discharges to Water Quality Impaired Waters
Using the GIS mapping tool ( along with the most current 303(d) list published on the division's publications web site, the MS4 must determine whether stormwater discharges from any part of the MS4 contribute pollutants of concern to an impaired waterbody.

Whom Do I Contact For Applications, Assistance And Other Sources of Information?

For more information please contact the local TDEC Environmental Field Office.