DEQ Releases 2026 Idaho Water Standards Review

The Idaho Department of Environmental Quality released the 2026 Triennial Review of Idaho Water Quality Standards on September 9, 2026. The review will guide water quality standards rulemaking and subprogram development for the next three years. It serves as the department’s planning framework for upcoming water quality standards work.

Section 303(c) of the Clean Water Act requires states to review, modify, and adopt water quality standards at least once every three years. As part of this triennial process, states consider public concerns, guidance from the U.S. Environmental Protection Agency, and new scientific and technical information. The review ensures that state water quality standards remain current and scientifically supported.

To facilitate public participation, the department published three water quality standards issue papers for public review. The agency also hosted two in-person meetings in Lewiston and Idaho Falls and a hybrid meeting in Boise. These meetings communicated triennial review requirements, presented proposed issues for prioritization, and solicited feedback from stakeholders.

Materials related to the 2026 Triennial Review are available on the department’s Water Quality Standards webpage under the Triennial Review drop-down. The agency lists India Southern, Water Quality Standards Analyst, as the contact for additional information at india.southern@deq.idaho.gov. The news post documenting the release carries the publication date of September 9, 2026.