Water Quality

Oregon's temperature standard

Oregon’s current temperature standard was adopted by the Oregon Environmental Quality Commission in December 2003. The Environmental Protection Agency approved much of the standard in March 2004, and approved additional provisions in March 2010. DEQ revised the standard in February 2007 in response to EPA’s disapproval of the 2003 narrative criteria for cool water species, natural lakes and oceans and bays. EPA approved the revised narratives in February 2011.

Additional resources

Lower Willamette Cold Water Refuge Study

DEQ completed a study of the availability and sufficiency of cold-water refuge (CWR) to support salmon and steelhead migration in the lower 50 miles of the Willamette River. The Lower Willamette CWR study assesses Oregon’s cold-water refuge narrative criteria to address the jeopardy decision and reasonable and prudent alternatives from the 2015 National Marine Fisheries Service (NMFS) Biological Opinion on the U.S. EPA approval of Oregon’s 2003 water temperature standards, with an emphasis on CWR to support migration of threatened and endangered salmon and steelhead populations. 

DEQ’s study identifies the location, source, and levels of use of CWR habitat available to adult and juvenile Upper Willamette River spring chinook, Upper Willamette River winter steelhead, Lower Columbia River Chinook, and Lower Columbia River winter steelhead populations that migrate through the designated migration corridor.

DEQ submitted the study to NMFS on March 18, 2020.

Additional resources

On Aug. 8, 2013, EPA disapproved the natural conditions criterion contained in Oregon’s water quality standard for temperature. EPA also disapproved the general natural conditions criterion contained in Oregon’s statewide narrative criteria, which applied to other naturally occurring substances and conditions of water. See the “Questions and Answers” and the EPA action letter below for additional information.



Debra Sturdevant
Water Quality Standards Coordinator

James McConaghie
Water Quality Standards Program