NPDES Stormwater Permit for Canyon Highway District #4 MS4 in Idaho

Transfer of permitting authority to Idaho. As of July 1, 2021, EPA has transferred authority to administer and enforce this permit to the Idaho Department of Environmental Quality. For more information, visit Idaho Pollutant Discharge Elimination System (IPDES) Program.

Below are EPA's National Pollutant Discharge Elimination System (NPDES) municipal separate storm sewer system (MS4) final permit and supporting documents for the Canyon Highway District (CHD) #4 in Idaho.

Permit number: IDS028134
Effective date: February 1, 2021
Permit expires: January 31, 2026

NPDES Permit, Canyon Highway District No. 4 MS4, Idaho, #IDS028134 (pdf) (633.71 KB, December 8, 2020)
Final stormwater permit.
Appendix B1: Stormwater Management Program Template, MS4 Permit #IDS028134 (pdf) (986.82 KB)
Optional template for creating or revising Stormwater Management Program (SWMP) document.
Appendix B2: Annual Report Form, MS4 Permit #IDS028134 (pdf) (866.61 KB)
Format for annual report. Due no later than December 1 of each year.
NPDES Permit Fact Sheet for Ada County Highway District MS4, Canyon Highway District No. 4 MS4, and Idaho Transportation Department District 3 MS4 (pdf) (1.74 MB, September 2020)
Technical basis for NPDES stormwater permits: #IDS028185, #IDS028134, #IDS028177.