Delta County Lake Quality

Delta County has 1 graded lakes — a thin enough sample that one or two stressed lakes can move the county average noticeably. Use the per-lake pages below for what actually matters. On average, Delta County lakes grade an A. That puts it near the top of the Michigan county ranking.

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. Mi49b Lake (A) is the cleanest in the county.