North Carolina Lake Water Quality

{{stateName}} has 151 graded lakes in our dataset, sampled across 57 counties, drawing on monitoring by {{agency}} plus federal and volunteer measurements. Only about 8% of {{stateName}}'s lakes pull an A grade — the smaller, agricultural-watershed lakes that dominate the dataset tend to carry persistent nutrient loads. 42% of lakes fall in the D or F brackets.

Eutrophic conditions dominate — nutrient-loaded, productive, with algal pressure that shows up most years in late summer. These lakes tend to be shallow, agricultural-watershed, and over-warmed by the time July ends. The cleanest county on average is Graham (grade A); the most-stressed is Union. The gap between the top and bottom counties is large enough that "{{stateName}} lake water quality" hides real local variation.