Malheur County Lake Quality

There are 39 monitored lakes in Malheur County. The mix is varied enough that the county-level average tells you the broad strokes, not the choose-this-cabin specifics. 2 of those lakes carry an A–F grade. The county-level summary describes that subset, not every water body listed. On average, Malheur County lakes grade D, with phosphorus loading and reduced clarity showing up across most of the dataset.

Most of the county's monitored lakes are shallow — under 50 feet — which means wind keeps the water column mixed all summer and sediment-bound phosphorus releases back into the surface layer whenever the bottom is disturbed. Bully Creek Lake (D) is the cleanest in the county.