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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.

The 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", the EPA has made a reasonable effort to identify parts of the standards that are disapproved or are otherwise not in effect for CWA purposes.

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State Standards in Effect for CWA Purposes

  • [See Article 2. Water Quality Standards ]
    (Effective May 20, 2015) This document contains water quality standards for all State waters.
    Note: EPA disapproved variance provisions contained at 327 IAC 2-1.5-17(b), 327 IAC 5-3-4.1(b)(1), and provisions for determining reasonable potential for whole effluent toxicity at 327 IAC 5-2-11.5(c)(1).  These provisions are replaced by federal Great Lakes Guidance provisions contained at 40 CFR 132, Appendix F, Procedure II, Section C, paragraph 1; 40 CFR 132, Appendix F, Procedure 5, Section F, paragraph 2; and 40 CFR 132, Appendix F, Procedure 6, Section C, paragraph 1 and Section D, respectively.
  • [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

Federal Clean Water Act Determinations that New or Revised Standards Are Necessary

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