DEQ is in the process of revising multiple temperature TMDLs that were issued by DEQ and approved by EPA between 2004 and 2010, including the Umpqua River Basin Temperature TMDL. EPA and the State of Oregon are working collaboratively under a federal court order to reissue these temperature TMDLs to make them consistent with current temperature standards. These TMDLs must be updated because they were based, in part, on the Natural Conditions Criterion, a section of the temperature standard that was subject to litigation and that the EPA determined should not be used to establish TMDLs.
EPA issued the Umpqua River Basin Temperature TMDL replacement on June 27, 2025. Find the TMDL replacement at EPA's Umpqua River Basin Temperature TMDLs web page.
DEQ will initiate the public process to replace the Umpqua temperature Water Quality Management Plan in 2025. Find out more at the Umpqua River Basin Temperature TMDL replacement web page.