1
ALacey Keosauqua Lake
Van Buren County, Iowa · 2.1 mi from Lake Sugema
- +Two grade letters higher (F → A)
- ++4.8 ft water clarity
- +Lower phosphorus (21.5 vs 57 µg/L)
Cleaner Lakes Than Lake Sugema
2 higher-graded lakes within 30 miles, ranked by grade improvement and proximity.
Lake Sugema carries a Grade F (Algae-prone) water quality score. Within 30 miles, 2 lakes hold a higher grade. Lacey Keosauqua Lake (Van Buren County, Grade A, 2.1 mi away) is the closest meaningful upgrade.
Reviewed by LakeQuality Editorial Team · Updated
2
BPoll Miller Park Lake
Lee County, Iowa · 29 mi from Lake Sugema
- +Two grade letters higher (F → B)
- ++3.6 ft water clarity
- +Lower phosphorus (28 vs 57 µg/L)
Reading the cohort
Only 2 lakes within a 30-mile radius score better than Lake Sugema's Grade F. The narrow set of options reflects either a fairly clean lake to begin with or a region without a wide range of cleaner alternatives — the trip-planning decision is more constrained than the headline "cleaner lakes nearby" suggests.
The closest cleaner alternative — Lacey Keosauqua Lake in Van Buren County, Grade A — sits 2.1 miles from Lake Sugema. At that distance, the substitution cost is essentially zero: same drive time, same regional access, demonstrably cleaner water on the EPA indicators. For repeat visitors who care about clarity or phosphorus levels, swapping the routine to Lacey Keosauqua Lake is mostly a habit change rather than a logistics change.
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.