Water Quality Standards Regulations: Delaware

Presented 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. 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. Additionally, please note the documents may also contain provisions that the EPA does not have the authority and duty to act on under the Clean Water Act because the provisions are not water quality standards.

• State Standards in Effect for CWA Purposes
• Federally Proposed or Promulgated Standards

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State Standards in Effect for CWA Purposes

• State of Delaware Surface Water Quality Standards (pdf) (565.46 KB)
  (Effective June 2, 2023) State regulation establishing water quality standards for surface waters of the state.
• Delaware River Basin Commission, Administrative Manual-Part III, Water Quality Regulations (pdf) (1018.9 KB)
  (Effective July 8, 2014) This document is incorporated into Delaware’s water quality standards by reference.

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Federally Proposed or Promulgated Standards

• Proposed Rule: Water Quality Standards to Protect Aquatic Life in the Delaware River