Beaverhead County Lake Quality

There are 28 monitored lakes in Beaverhead County. The mix is varied enough that the county-level average tells you the broad strokes, not the choose-this-cabin specifics. 1 of those lake carry recent nutrient and algae readings. The county-level summary describes that subset, not every water body listed. The county's readings sit in the middle of the Montana range, with one or two lakes pulling the average up or down depending on year.

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. Clark Canyon Reservoir has the lowest nutrient and algae readings in the county.