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Idaho NPDES Program Authorization

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On June 5, 2018, the EPA Administrator approved the application by the State of Idaho to administer and enforce the Idaho Pollutant Discharge Elimination System (IPDES) Program. Concurrent with this approval, EPA also approved IPDES program for electronic reporting.

The Idaho Department of Environmental Quality (IDEQ) will administer the approved IPDES program regulating discharges of pollutants into waters of the United States under its jurisdiction. For more information, visit Idaho Department of Environmental Quality Permit OptionsExit.

EPA has approved the State's implementation plan that transfers the administration of specific program components from EPA to the State over a four-year period in accordance with the Memorandum of Agreement (MOA) between IDEQ and EPA Region 10, and subject to EPA oversight and enforcement. EPA will suspend issuance of NPDES permits in Idaho in accordance with the schedule.

EPA will retain the authority to issue NPDES permits for facilities located on tribal lands and/or discharging to tribal waters.

For more information:

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Schedule for the Transfer of Permitting Authority to Idaho

  • Phase I – Individual Municipal Permits and Pretreatment on July 1, 2018.
  • Phase II – Individual Industrial Permits on July 1, 2019.
  • Phase III – General Permits (Aquaculture, Pesticide, CAFO, Suction Dredge, Remediation) on July 1, 2020.
  • Phase IV – Federal Facilities, General and Individual Stormwater Permits and Biosolids on July 1, 2021.

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Public Outreach

EPA accepted public comments and testimony on Idaho's IPDES application from August 11 through October 10, 2017. Documents related to the public comment period, including EPA's responses to comments, are available at the link below.

Related information:

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Application Documents

Idaho submitted the following documents to EPA on August 31, 2016 (and updated on August 1, 2017) as part of its program submission.

The following links exit the site Exit
  1. Letter from Idaho governor to EPA requesting approval of State's application (PDF)(2 pp, 488 K, About PDF) - August 9, 2016
  2. IPDES Program Description (PDF)(443 pp, 26 MB) - Revised July 2017. Document describes how the state will issue IPDES permits, ensure compliance with permit conditions, conduct enforcement, as well as fund and manage the program including programmatic information and data.
  3. Statement from Idaho Attorney General's Office (PDF)(92 pp, 1 MB) - August 1, 2017. Letter and supporting information confirming that the state’s laws and regulations provide sufficient authority to the state to implement the discharge, pretreatment, and biosolids components of the NPDES program.
  4. Memorandum of Agreement (MOA) Between Idaho and EPA Region 10 (PDF)(76 pp, 2.8 MB) - Document establishes, in part, timeframes for a phased approach for the state to assume authority.
    • Note: On August 29, 2017, EPA provided a correction to Appendix F of the MOA (see "Additional Correspondence" below).
  5. Water Quality Planning in Idaho: Continuing Planning Process (PDF)(4 pp, 261 K)
  6. Applicable State statutes and regulations:

To review supplemental documents, visit Idaho Pollutant Discharge Elimination System Primacy Application.Exit

Additional Correspondence

You may need a PDF reader to view some of the files on this page. See EPA’s About PDF page to learn more.