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Water Quality Standards Regulations: Ohio

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
Federally Proposed or Promulgated Standards

State Standards in Effect for CWA Purposes

[See Ohio Water Quality Standards 3475-1-01 through 3475-1-44 and 3475-1-50 through 3475-1-54 ]
(Effective August 28, 2018) This document establishes water quality requirements for all surface waters of the state.

Federally Proposed or Promulgated Standards

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Ohio Water Quality Standards 3475-1-01 through 3475-1-44 and 3475-1-50 through 3475-1-54 (PDF)(541 pp, 7 MB)