Lake Kathryn
Seminole County, FloridaView mapDirections
Florida DEP publishes the water-quality measurements for Lake Kathryn. Here is what has been measured.
- Eutrophic
- 47 ft max depth
Lake Kathryn in Seminole County, Florida has water-quality measurements published by Florida DEP, shown here as reported. Water clarity: 3 ft visibility. Phosphorus: 25 µg/L.
Lake Kathryn is a productive, nutrient-rich eutrophic lake in Seminole County, Florida with an estimated average depth of about 47 feet. Overall water quality is improving over recent sampling years. Compared to the 121 other monitored lakes in Seminole County, Lake Kathryn ranks #38 for water quality.
Source: EPA Water Quality Portal sampling records, FDEP, last sampled 2025-03-31. Methodology: how these readings are compared.
Swimming conditions
Readings onlyBacteria tested: low
Based on clarity and algae readings from past sampling — there is no live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Based on E. coli testing, Lake Kathryn never exceeded the EPA safe-swimming threshold (235 MPN/100mL) — on 0% of 19 samples across 6 seasons.
This is a historical summary of past testing, not a current condition — bacteria levels change quickly, especially after rain. Always check Florida’s current beach and health-department advisories before swimming.
Whether Lake Kathryn 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 Kathryn
These are the measurements Florida DEP publishes for Lake Kathryn, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Very murky, less than 3 ft of visibility. Phosphorus 25 µg/L. TSI 56.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 3ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 25µg/L | Good GoodFairPoor |
| 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. | 56 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Lake Kathryn
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Lake Kathryn typically sits around 84°F at the surface in October. Summer average is about 87°F. Usually warmest in Aug (about 88°F) and coldest in Jan (about 65°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (65°F) to its warmest (88°F).
Typical surface water temperature by month, from 50 field readings (2019–2025) via the EPA Water Quality Portal. See the full Lake Kathryn water temperature breakdown →
Lake Details
Max depth
~47 ft est.
Depth marked “est.” is a modeled maximum from GLOBathy (Khazaei et al. 2022, CC0), not a measured survey. Florida has not published bathymetry for Lake Kathryn.
Lake Size & Watershed
Watershed (drainage) area
2 sq mi
HydroLAKES / HydroSHEDS
Surface area
64 acres
HydroLAKES / HydroSHEDS
Shoreline
1.2 mi
HydroLAKES / HydroSHEDS
Elevation
39 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS). Mean depth here is modelled, not surveyed — HydroLAKES v1.0 estimates lake depth from surrounding terrain rather than from soundings. Treat it as an approximation, and prefer a state bathymetric survey where one exists.
Stays via Stay22
Stays near Lake Kathryn
Compare lakeside cabins, hotels, and vacation rentals near Lake Kathryn in Seminole 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 Kathryn
Prices for Oct 16–18, 4 adults. Change dates on the map below.
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Planning a whole trip? See where to stay at Florida’s top lakes →
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Fishing Lake Kathryn
Water Quality Trend: Improving
Based on 5 years of monitoring (2020–2024).
Water clarity
Improving5 years
Phosphorus
Improving-1.45 µg/L/yr5 years
Nearby Lakes in Seminole County
Frequently asked questions about Lake Kathryn
Where is Lake Kathryn?
- Lake Kathryn is a lake in Seminole 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 Kathryn?
- Lake Kathryn in Seminole County, Florida has water-quality measurements published by Florida DEP, shown here as reported. Water clarity: 3 ft visibility. Phosphorus: 25 µg/L.
Is Lake Kathryn safe to swim in?
- Based on E. coli testing, Lake Kathryn never exceeded the EPA safe-swimming threshold (235 MPN/100mL) — on 0% of 19 samples across 6 seasons. That is a historical summary of past bacteria testing, not a current reading and not a swimming clearance. Bacteria levels can spike quickly after heavy rain, so whether Lake Kathryn is safe to swim in today is a call for Florida's water agency and the county health department; check their current beach advisories before you swim.
What is the water temperature of Lake Kathryn?
- Lake Kathryn typically sits around 84°F at the surface in October, from 50 EPA Water Quality Portal field readings (2019–2025). That is a typical value for the month, not a live reading.
How deep is Lake Kathryn?
- No published bathymetric survey covers Lake Kathryn, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 47 feet, but that is a modelled estimate derived from surrounding terrain rather than a measurement on the water, so treat it as approximate.
Explore Lake Kathryn across LakeQuality
Planning a trip around Canaveral?
Lake Kathryn is about 36 miles from Canaveral National Seashore. Crowds there swing hard by season, so the month you pick changes both how busy the park is and what lodging costs.
Best time to visit Canaveral →More lakes in Florida
Other Lakes in Florida
Eutrophic Lakes in Florida
Where this data comes from
66 measurements from 3 monitoring stations, 2020–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Submitting organization not recorded for these samples38 samples · 2020–2025
- Submitting organization not recorded for these samples28 samples · 2022–2024
Monitoring station identifiers (3)
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
Lake size & watershed from HydroLAKES (HydroSHEDS)