Adopted rule
Administrative Order No.: DEQ-33-2025
Filed and Effective: Dec. 2, 2025
See Oregon Bulletin, January 2026
Rulemaking contact: Aron Borok, 503-887-1173
On Nov. 21, 2024, in response to a rulemaking petition from Marion County, the Oregon Environmental Quality Commission directed DEQ to start rulemaking proceedings to revise the Three Basin Rule.
The Three Basin Rule provides additional protections beyond those usually provided by the Clean Water Act in three watersheds that are major drinking water sources – the Clackamas, North Santiam and McKenzie basins. The current Three Basin Rule prohibits new or expanded wastewater discharges in these basins, with some specific exceptions. The adopted rule revisions allow DEQ to issue new water quality permits that allow facilities to discharge to these basins under limited circumstances consistent with the stated objectives of the Three Basin Rule.
The rulemaking process included convening a rule advisory committee to develop the rules, posting draft rules for public comment, holding a public hearing, and propose final rules to the EQC for adoption.
DEQ is convened an advisory committee to review the technical issues and fiscal impacts related to the proposed rules. In convening this committee, DEQ appointed members that reflect the range of entities that are both directly and indirectly affected by proposed changes to the rules.
Meeting 3: July 14, 2025
Previous meetings
Permitting Seminar: June 30, 2025
Meeting 2: May 22, 2025
Meeting 1: March 31, 2025