Pinellas-Autu Lake
Pinellas-Autu Lake in Pinellas County, Florida has a water quality grade of C (Fair). Water clarity: 2.8 ft visibility. Phosphorus: 49 µg/L.
- Clarity
- 2.8 ft
- Type
- Eutrophic
- Trend
- ↑ Improving
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Pinellas-Autu Lake is a productive, nutrient-rich eutrophic lake in Pinellas County, Florida. Water quality is graded C based on 1 sampling years through 2025. Overall water quality is improving over recent sampling years. Compared to the 33 other monitored lakes in Pinellas County, Pinellas-Autu Lake ranks #12 for water quality.
Source: EPA Water Quality Portal sampling records, FDEP, last sampled 2025-02-16. Grade methodology: LakeQuality methodology.
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Swimming Safety
Grade onlyBacteria advisory
Based on clarity and algae grades from past sampling — we do not hold live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Generally safe for swimming, moderate water quality
Water Quality Grade: C (Fair)
Very murky, less than 2.8 ft of visibility. Phosphorus level: 49 µg/L. Trophic State Index: 61.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 2.8 ft | Not graded |
| Phosphorus | 49 µg/L | Fair |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 61 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Where to stay near Pinellas-Autu Lake
Compare lakeside cabins, hotels, and vacation rentals near Pinellas-Autu Lake in Pinellas County, Florida — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water.
Top-rated places to stay near Pinellas-Autu Lake
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Fishing Pinellas-Autu Lake
Water Quality Trend: ↑ Improving
Based on 5 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↑ Improving | +0.85 m/yr | 5 |
| Phosphorus | ↑ Improving | -87.1 µg/L/yr | 5 |
EPA Impairment Status
Pinellas-Autu Lake is officially listed as impaired under Clean Water Act §303(d) in the 2022 EPA reporting cycle (IR category 5).
Causes of impairment
Source: EPA ATTAINS assessment unit FL1508A · Official waterbody report · Matched by proximity (0.82 km)
County Ranking
Ranked #12 of 34 lakes in Pinellas County
Nearby Lakes With Higher Grades
Pinellas-Autu Lake holds Grade C. 2 nearby lakes hold higher nutrient-and-algae grades — useful for a swim day, not a reason to skip lodging here.
See full comparison →Nearby Lakes in Pinellas County
Frequently asked questions about Pinellas-Autu Lake
Where is Pinellas-Autu Lake?
- Pinellas-Autu Lake is a lake in Pinellas County, Florida. LakeQuality grades it C for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for Pinellas-Autu Lake?
- Pinellas-Autu Lake in Pinellas County, Florida has a water quality grade of C (Fair). Water clarity: 2.8 ft visibility. Phosphorus: 49 µg/L.
Is Pinellas-Autu Lake safe to swim in?
- Generally safe for swimming, moderate water quality. Pinellas-Autu Lake has a water quality grade of C (Fair). Always check local health department advisories before swimming.
Explore Pinellas-Autu Lake across LakeQuality
More Florida Lake Rankings
Other Grade C Lakes in Florida
Eutrophic Lakes in Florida
Where this data comes from
76 measurements from 2 monitoring stations, 2023–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- FLORIDA LAKEWATCH
21FLKWAT_WQX76 samples · 2023–2025
Monitoring station identifiers (2)
Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See how grades are calculated and data sources.
Other records on this page
Impairment status from EPA ATTAINS 303(d) database