Pinellas-Seminole Lake
Pinellas County, FloridaEutrophic
Pinellas-Seminole Lake is a productive, nutrient-rich eutrophic lake in Pinellas County, Florida. Water quality is graded D based on 2 sampling years through 2025. Compared to the 54 other monitored lakes in Pinellas County, Pinellas-Seminole Lake ranks #35 for water quality.
Source: EPA Water Quality Portal sampling records, Florida DNR, last sampled 2025-04-14. Grade methodology: LakeGrade methodology.
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Swimming Safety
Swimming not recommended, poor water quality with high algae risk
Water Quality Grade: D, Poor
Very murky, less than 1.5 ft of visibility. Phosphorus level: 63 µg/L. Trophic State Index: 68.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 1.5 ft | F |
| Phosphorus | 63 µg/L | D |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 68 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Location
County Ranking
Ranked #35 of 55 lakes in Pinellas County
Nearby Lakes in Pinellas County
More Florida Lake Rankings
Other Grade D Lakes in Florida
Eutrophic Lakes in Florida
Data Sources
Water quality data from the EPA Water Quality Portal
Grading methodology based on Metropolitan Council standards
Most recent sample: 2025-04-14
Monitoring stations: 3
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