St Lucie-Margaret Lake
- +Higher grade (C → B)
- ++1.1 ft water clarity
- +Lower phosphorus (22 vs 46 µg/L)
4 higher-graded lakes within 30 miles, ranked by grade improvement and proximity.
St Lucie-de Witt Lake carries a Grade C (Fair) water quality score. Within 30 miles, 4 lakes hold a higher grade. St Lucie-Margaret Lake (St. Lucie County, Grade B, 0.4 mi away) is the closest meaningful upgrade.
4 cleaner lakes sit within 30 miles of St Lucie-de Witt Lake in the EPA water-quality dataset. With that many higher-grade neighbors close by, St Lucie-de Witt Lake's Grade C reflects something specific to the lake itself — not a regional water-quality ceiling. The neighbor list below isn't a small set of marginal upgrades; it's a real cohort of meaningfully cleaner choices for the same Florida weekend.
The closest cleaner alternative — St Lucie-Margaret Lake in St. Lucie County, Grade B — sits 0.4 miles from St Lucie-de Witt Lake. 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 St Lucie-Margaret Lake is mostly a habit change rather than a logistics change.
The EPA water-quality grading combines clarity (Secchi depth), phosphorus, and chlorophyll-a measurements from state environmental sampling. A higher letter grade reflects measurably cleaner water on those indicators, 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. See the methodology page for the full grading formula.
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.