This rulemaking seeks to adopt the Water Quality Management Plan that implements the
Umpqua River Basin Temperature TMDL that EPA issued June 27, 2025.
In 2013, the U.S. Environmental Protection Agency disapproved the Natural Conditions Criterion contained in Oregon's water quality standard for temperature due to the 2012 U.S. District Court decision for NWEA v. EPA, 855 F. Supp. 2d 1199 (D. Or., 2012). This portion of the temperature water quality standard was used in most temperature TMDLs issued from 2003 through 2012. On Oct. 4, 2019, the U.S. District Court issued a judgment for NWEA v. EPA, No. 3:12-cv-01751-HZ (D. Or., Oct. 4, 2019) and required DEQ and EPA to replace 15 Oregon temperature TMDLs that were based on the Natural Conditions Criterion and to reissue the temperature TMDLs based on the remaining elements of the temperature water quality standard.
The updated
Umpqua
River Basin Temperature TMDL fulfills this requirement.
DEQ will now develop a revised WQMP to describe the implementation responsibilities and strategies for meeting temperature targets established in the TMDL.
For information more information visit Umpqua Temperature TMDL Replacement Project web page.
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Advisory committee
DEQ is convening an advisory committee to review the technical issues and fiscal impacts related to the proposed rules. In convening this committee, DEQ has appointed members that reflect the range of entities that are both directly and indirectly affected by proposed changes to the rules.
Meeting 1: Feb. 18, 2026, 10 a.m. to 11:30 a.m. Pacific TimeMeeting ID: 827 8099 6858
Meeting 2: Apr. 29, 2026, 10 a.m. to 11:30 a.m. Pacific Time