Thonotosas Lake
Thonotosas Lake in Hillsborough County, Florida is not rated for water quality — its monitoring record does not meet the evidence bar.
- Typical in June
- 83°F
- Trend
- → Stable
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Why Thonotosas Lake has no grade
We grade a lake only when the monitoring record supports a letter: at least three phosphorus or chlorophyll-a samples in the last ten years, scored against EPA National Lakes Assessment thresholds for this lake’s ecoregion. For Thonotosas Lake, no nutrient or algae measurement meets the evidence bar (at least 3 samples within 10 years).
Not Rated is not an F. It is EPA Integrated Reporting Category 3 — insufficient information. The water here may be excellent or poor; nobody has measured enough of it to say. Everything below that has been measured is still reported on this page.
Sampling is run by FDEP and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Thonotosas Lake is a lake in Hillsborough County, Florida. Water clarity is improving over recent sampling years.
Source: EPA Water Quality Portal sampling records, FDEP, last sampled 2024-04-17. Grade methodology: LakeQuality methodology.
Watch Thonotosas Lake water quality
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Swimming Safety
Not ratedLimited data
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for Thonotosas Lake
These readings exist but are not enough for an A–F grade — see why.
No clarity data.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | No recent samples | |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples |
Where to stay near Thonotosas Lake
Compare lakeside cabins, hotels, and vacation rentals near Thonotosas Lake in Hillsborough 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 Thonotosas Lake
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Water Temperature
Thonotosas Lake typically sits around 83°F at the surface in June. Summer average is about 83°F. Usually warmest in Jun (about 83°F) and coldest in Apr (about 76°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 8 field readings (2012–2024) via the EPA Water Quality Portal. See the full Thonotosas Lake water temperature breakdown →
Fishing Thonotosas Lake
Water Quality Trend: → Stable
Based on 6 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↑ Improving | +0.029 m/yr | 6 |
| Phosphorus | ↓ Declining | +8.56 µg/L/yr | 6 |
EPA Impairment Status
Thonotosas Lake is officially listed as impaired under Clean Water Act §303(d) in the 2022 EPA reporting cycle (IR category 5).
Causes of impairment
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit FL1522B · Official waterbody report · Matched by proximity (0.09 km)
Graded lakes near Thonotosas Lake
Thonotosas Lake has no grade, but these lakes within a short drive do.
Nearby Lakes in Hillsborough County
Frequently asked questions about Thonotosas Lake
Where is Thonotosas Lake?
- Thonotosas Lake is a lake in Hillsborough County, Florida. LakeQuality has not rated this lake (UNRATED) — no nutrient or algae measurement meets the evidence bar (at least 3 samples within 10 years).
What is the water quality grade for Thonotosas Lake?
- Thonotosas Lake in Hillsborough County, Florida is not rated for water quality — its monitoring record does not meet the evidence bar.
Is Thonotosas Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Thonotosas Lake is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
What is the water temperature of Thonotosas Lake?
- Thonotosas Lake typically sits around 83°F at the surface in June, from 8 EPA Water Quality Portal field readings (2012–2024). That is a typical value for the month, not a live reading.
Explore Thonotosas Lake across LakeQuality
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Where this data comes from
2 measurements from 1 monitoring station, 2024. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Submitting organization not recorded for these samples2 samples · 2024
Monitoring station identifiers (1)
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