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Pollution reduction plan to improve health of Klamath and Lost rivers
Klamath Falls, OR—The Oregon Department of Environmental Quality issued a plan for reducing water temperature in the Upper Klamath and Lost River watersheds—a step crucial for improving the health of these rivers.

Too much heat in rivers and streams—caused by removal of streamside vegetation, warm wastewater discharges and some irrigation activities—is harmful to fish and aquatic life. Excessive heat reduces oxygen, increases effects of toxins and alters the natural environment native species need to survive.

“This much-needed plan puts Oregon on a path toward restoring water quality and protecting our precious natural resources in the Klamath Basin,” said DEQ Director Richard Whitman. “It’s a complex task, and we’re grateful for the ongoing collaboration with our Klamath-area partners whose efforts will ultimately make this goal a reality.”

The plan is called a Total Maximum Daily Load, or TMDL. A TMDL is the maximum amount of pollution—in this case heat—that can be present in a waterbody without exceeding water quality standards set to protect people and aquatic life. It determines the amount and source of pollutants entering the river system, and allocates “pollutant loads” to each source at levels that will ultimately restore water quality to clean water standards.

The Upper Klamath and Lost River Subbasin Temperature TMDL addresses water quality in areas south of Upper Klamath Lake. The TMDL identifies the cities, counties, federal and state agencies, irrigation districts and industrial facilities that must work together to reduce warming of the Klamath and Lost Rivers and their tributaries. DEQ will work with these entities to develop and implement management plans to improve water quality.

DEQ accepted public comments on the draft plan May 15 to July 15, receiving 14 sets of comments. DEQ made revisions to pollutant load allocations and other aspects of the plan in response to the comments.

The temperature TMDL must be approved by the U.S. Environmental Protection Agency. The EPA must approve the TMDL by Sept. 30, 2019 to comply with a court order.

DEQ issued and EPA approved a separate TMDL earlier this year for managing nutrient pollution—dissolved oxygen, pH, ammonia and nuisance algae—in the same areas of the Upper Klamath and Lost River Subbasins.

Find more information about the TMDLs at

Media contact: Laura Gleim, DEQ public affairs specialist, 541-633-2030,



Environment & Energy