DEQ: Nitrate found in 65 of 100 domestic wells in southern Deschutes County; county considers targeted sewer and treatment investments

The Oregon Department of Environmental Quality reported Thursday that its 2023–24 sampling of 100 domestic wells in southern Deschutes County detected nitrate in 65 wells; three samples exceeded the Oregon state action level of 7 milligrams per liter, and two exceeded the U.S. Environmental Protection Agency's maximum contaminant level of 10 milligrams per liter, with the highest reading at 23 milligrams per liter.

Those findings, presented at the Deschutes County Board of Commissioners meeting in the Allen Room, are based on raw lab results that DEQ said are still undergoing full quality assurance and analysis before a formal report is published later this year. "Results detected nitrate in 65 of those wells and 3 were above the state action level of 7 milligrams per liter," said Greg Sweeland, who works in DEQ's Bend office and helped lead the sampling project. He said DEQ provides results to well owners and refers exceedances to public health…