Cleaner Lakes Than Summit Lake

Reading the cohort

Within 30 miles of Summit Lake, 3 lakes score higher on EPA water-quality metrics than its Grade F. The short list means the alternatives are real upgrades but not interchangeable — each carries its own access, size, and species mix worth checking before substituting it into a weekend plan.

Three Mile Lake (Union County, Grade D) is the closest cleaner option at 9.6 miles from Summit Lake — close enough to be a genuine substitute for most users, far enough that it isn't the same neighborhood lake. Worth the trip if water quality is the primary driver; less obvious if Summit Lake is on the way to other plans.

Lakes are graded A to F on nutrients and algae — total phosphorus, total nitrogen, chlorophyll-a, and turbidity — measured against the EPA National Lakes Assessment 2022 condition classes for that lake's own ecoregion, so a lake is judged against the lakes it would naturally resemble. A higher letter reflects measurably lower nutrient and algae levels, not subjective beauty or access quality — a Grade A lake might have worse boat-launch facilities or shoreline access than a Grade C neighbor, so the ranking is one input alongside the rest of trip planning. The full grading formula is on our methodology page.

How this list is built

Rated lakes on LakeQuality have a letter from EPA Water Quality Portal samples — nutrients and algae measured against EPA National Lakes Assessment ecoregion classes. Secchi is shown, not scored. To suggest cleaner alternatives, we filter lakes within 30 miles to those with a strictly higher numeric score, then rank by grade improvement with a small proximity tiebreak. Cross-state and limited-data lakes are excluded so the list stays locally relevant.