Weld County Lake Quality

Weld County has 55 monitored lakes, enough that within-county variation matters as much as the county average. Some are deep glacial basins, others are shallow agricultural-watershed waters, and the measurements reflect that mix. 4 of those lakes carry an A–F grade. The county-level summary describes that subset, not every water body listed. On average, Weld County lakes grade D, with phosphorus loading and reduced clarity showing up across most of the dataset.

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. Windsor Lake (D) is the cleanest in the county.