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  2. NPDES Permits Around the Nation

NPDES Permit for Dworshak Dam in Idaho

Related Information
  • Enforcement and Compliance Online (ECHO) Detailed Facility Report
  • NPDES permits in Idaho

Below is EPA's National Pollutant Discharge Elimination System (NPDES) permit for the U.S. Army Corps of Engineers Dworshak Dam located on the Nez Perce Reservation near Ahsahka, Idaho.

  • Permit number: ID0028586
  • Effective date: April 1, 2024
  • Modified: June 13, 2024
  • Permit expires: March 31, 2029

  • NPDES Permit, Dworshak Dam, Idaho, #ID0028586 (pdf) (437.5 KB, June 13, 2024)
    Final discharge permit including 2024 minor modification.
  • Water Quality Certification for NPDES Permit, Dworshak Dam, Idaho, #ID0028586 (pdf) (71.05 KB, September 20, 2023)
    EPA's certification that the NPDES permit complies with section 401 of the Clean Water Act and Nez Perce Tribal law.
  • Response to Comments on Draft NPDES Permit, Dworshak Dam, Idaho, #ID0028586​ (pdf) (196.49 KB, September 2023)
    EPA's responses to public comments received on its September 2022 draft permit.
  • NPDES Permit Fact Sheet, Dworshak Dam, Idaho, #ID0028586 (pdf) (1.18 MB, September 2022)
    Technical basis for the September 2022 draft permit.
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Last updated on June 13, 2025
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