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Water Quality Programs

Knox County is a Phase II MS4

The Environmental Protection Agency's (EPA) National Pollutant Discharge Elimination System (NPDES), Phase II Stormwater Program for Municipal Separate Storm Sewer Systems (MS4s) is the second part of a program designed improve the quality of the nation's streams, rivers, lakes, and estuaries by managing stormwater runoff from urban and suburban areas, construction projects, and industrial sites.

Knox County’s NPDES Requirements:

As a Phase II MS4 community, Knox County is charged with reducing the discharge of stormwater pollutants to the maximum extent practicable, to protect water quality, and to satisfy the appropriate water quality requirements of the Clean Water Act. In order to meet these aims, EPA has defined the following six “minimum control measures” that are to be addressed:

  • Public Education & Outreach
  • Public Participation & Involvement
  • Illicit Discharge Detection & Elimination
  • Pollution Prevention/Good Housekeeping
  • Construction Site Stormwater Runoff Control
  • Permanent Stormwater Management

The Tennessee Department of Environment and Conservation, Division of Water Pollution Control (TDEC WPC) implements the EPA Phase II regulations in Tennessee. Knox County applied for permit coverage by submitting a Notice of Intent (NOI) in 2003. This NOI identifies the applicable requirements of the general permit and lists the BMPs and stormwater programs that the MS4 will use to meet the six minimum control measures. It is required that all the BMPs and stormwater programs proposed in the NOI be developed and implemented by 2008, at which time a new five-year permit will be issued.

Currently, 85 cities and counties are now covered under the Stormwater Phase II NPDES program. For a complete list of the designated Stormwater Phase II communities, visit the following website:

Where Are We Now?

TDEC has issued a draft of the new NPDES permit to Phase II MS4 communities. The public can comment on the draft until May 10, 2010. Please see our “News and Events” on our home page for links to the proposed permit and info on how you can comment. TDEC expects the new permit to be issued in June of 2010. Until then, Knox County will continue to work under the old permit and improve upon the programs related to the six minimum measures until the next permit is issued.

The Tennessee Department of Environment and Conservation (TDEC) issued a new NPDES General Permit for Discharges from Small Municipal Separate Storm Sewer Systems on August 31, 2010. The permit became effective on October 1, 2010 and is set to expire on September 1, 2015. All previously permitted Phase II MS4 communities must submit a new Notice of Intent (NOI) within 90 days of the effective date of the NPDES permit to TDEC. Knox County is working on the NOI application and will submit it prior to the required date. More information about TDEC’s Phase II program can be found at their Stormwater Permitting Phase II MS4 website.

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205 West Baxter Avenue
Knoxville, TN 37917

Phone: 865-215-5540
Fax: 865-215-5831

Monday - Friday
8:00 am - 4:30 pm
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