Green Lake County Lake Quality

Green Lake County has 12 monitored 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. 5 of those lakes carry recent nutrient and algae readings. The county-level summary describes that subset, not every water body listed. For Green Lake County the spread behind the average matters more than the average itself: a few nutrient-rich lakes among many clear ones produce the same figure as the inverse.

Many of the county's lakes are deep glacial basins, over 50 feet at their deepest point, which gives them thermal stratification and a buffer against summer warming. Green Lake has the lowest nutrient and algae readings in the county.