Big Stone County Lake Quality

There are 36 monitored lakes in Big Stone 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 recent nutrient and algae readings. The county-level summary describes that subset, not every water body listed. The monitored lakes here are mostly shallow, productive basins where summer algae is common; each lake page shows its own readings beside the EPA condition class.

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. Big Stone Lake has the lowest nutrient and algae readings in the county.