EPA Supports NWEA’s On Dumping Hot Water Into Hyporheic Zones

In July 2013, NWEA sent a letter to EPA Region 10 in Seattle asking the agency to weigh in on the Oregon practice of letting – even encouraging – municipal dischargers to dump their wastes into hyporheic zones of rivers.  These hyporheic zones are where cold groundwater mixes with surface water, providing thermal refuges to cold-water fish and to a range of other species.  On March 20, 2014, EPA wrote Oregon DEQ to express its concern and opposition to this practice of “indirect discharges to environmentally important and sensitive areas.”  EPA went on to explain that it viewed “the permitting of discharges to the hyporheic zone as inconsistent with the intent of the State’s water quality standards,” and that the Clean Water Act “did not contemplating shifting pollution to groundwater as a means of avoiding direct discharges to surface water.”