Lake Thomas
Pasco County, FloridaView mapDirections
Florida DEP publishes the water-quality measurements for Lake Thomas. Here is what has been measured.
- Impaired · Algal growth
- Limited data
Lake Thomas in Pasco County, Florida has water-quality measurements published by Florida DEP, shown here as reported. Water clarity: 7.5 ft visibility. Phosphorus: 14 µg/L.
Lake Thomas is a lake in Pasco County, Florida. Overall water quality is declining over recent sampling years.
Source: EPA Water Quality Portal sampling records, FDEP, last sampled 2023-08-09. Methodology: how these readings are compared.
For a place on the water, look through cabin and lake-house rentals near Lake Thomas on Vrbo. For a hotel or motel room, Booking.com and Expedia both search around the lake.
Swimming conditions
No readingRecreation use not supported
Nutrient and algae readings are not a swimming clearance. Lake Thomas is listed impaired under Clean Water Act §303(d) (IR 5) for algal growth, nutrients (phosphorus, nitrogen). Check local advisories before you swim.
Whether Lake Thomas is safe to swim in today is a call for the Florida Department of Environmental Protection and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Lake Thomas
These are the measurements Florida DEP publishes for Lake Thomas, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Moderate clarity, visible to about 7.5 ft. Phosphorus 14 µg/L. TSI 45.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 7.5ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 14µg/L | Measured, not scored The nutrient that most limits algae growth in freshwater. More phosphorus, more algae potential. |
| Chlorophyll-a (algae) | No reading The green pigment in algae — a direct measure of how much algae is in the water. | |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 45 | Mesotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Moderate nutrients, good water quality
Ask about Lake Thomas
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Lake Thomas typically sits around 83°F at the surface in September. Summer average is about 90°F. Usually warmest in Aug (about 91°F) and coldest in Jan (about 59°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (59°F) to its warmest (91°F).
Typical surface water temperature by month, from 12 field readings (2010–2023) via the EPA Water Quality Portal. See the full Lake Thomas water temperature breakdown →
Stays via Stay22
Stays near Lake Thomas
Compare lakeside cabins, hotels, and vacation rentals near Lake Thomas in Pasco 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 Lake Thomas
Prices for Oct 16–18, 4 adults. Change dates on the map below.
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.
Planning a whole trip? See where to stay at Florida’s top lakes →
Follow Lake Thomas’s readings
Email me when new measurements post for this lake. Updates stay free.
Or email
Fishing Lake Thomas
Water quality readings over time
3 seasons of samples on record (2023–2025). Calling a direction takes at least 4 years of the same measurement.
Water clarity
Worsening3 years
Phosphorus
Worsening+0.5 µg/L/yr3 years
EPA Impairment Status
Lake Thomas is officially listed as impaired under Clean Water Act §303(d) in the 2022 EPA reporting cycle (IR category 5).
Causes of impairment
Designated uses not supporting: Aquatic life, Recreation.
Source: EPA ATTAINS assessment unit FL1456A · Official waterbody report
Nearby Lakes in Pasco County
Frequently asked questions about Lake Thomas
Where is Lake Thomas?
- Lake Thomas is a lake in Pasco County, Florida. Its water-quality measurements are published by Florida DEP and shown on this page as reported.
What is the water quality of Lake Thomas?
- Lake Thomas in Pasco County, Florida has water-quality measurements published by Florida DEP, shown here as reported. Water clarity: 7.5 ft visibility. Phosphorus: 14 µg/L.
Is Lake Thomas safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Lake Thomas is listed impaired under Clean Water Act §303(d) (IR 5) for algal growth, nutrients (phosphorus, nitrogen). Check local advisories before you swim.
What is the water temperature of Lake Thomas?
- Lake Thomas typically sits around 83°F at the surface in September, from 12 EPA Water Quality Portal field readings (2010–2023). That is a typical value for the month, not a live reading.
Explore Lake Thomas across LakeQuality
More lakes in Florida
Other Lakes in Florida
Mesotrophic Lakes in Florida
Where this data comes from
2 measurements from 1 monitoring station, 2023. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Submitting organization not recorded for these samples2 samples · 2023
Monitoring station identifiers (1)
EPA condition classes from the National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See where the data comes from and data sources.
Other records on this page
Impairment status from EPA ATTAINS 303(d) database