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Water Quality Standards Regulations: Indiana

Presented below are water quality standards in effect for Clean Water Act (CWA) purposes for this state.

EPA is posting these standards as a convenience to users and has made a reasonable effort to assure their accuracy. Also, for each document listed under "State Standards in Effect for CWA Purposes", EPA has made a reasonable effort to identify parts of the standards that are disapproved or are otherwise not in effect for CWA purposes.

On this page:

State Standards in Effect for CWA Purposes

  • [See Article 2. Water Quality Standards ]
    (Effective July 29, 2020) This document contains water quality standards for all State waters. Please note that not all provisions are effective for Clean Water Act purposes (refer to cover page for more information).
  • [See Article 5. 327 IAC 5-3.5. Streamlined Mercury Variance Requirements and Application Process ]
    (Effective December 20, 2005) Section 327 IAC 5-3.5 was added to establish a process and application requirements for obtaining a variance from the existing water quality criterion used to establish a water quality-based effluent limitation for mercury in wastewater discharges permitted under the National Pollutant Discharge Elimination System (NPDES) program.

Federally Proposed or Promulgated Standards

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