Linn County Lake Quality

There are 22 monitored lakes in Linn 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. With an average grade of B, Linn County sits comfortably above the Oregon median.

The county's lakes lean shallow, which makes the grades sensitive to wind, sediment-resuspension, and any nutrient inputs from the watershed. The cleanest lake on the books is Green Peter Lake (A); the most-stressed is Foster Lake (C).