Willis Lake
Orange County, FloridaView mapDirections
Florida DEP publishes the water-quality measurements for Willis Lake. Here is what has been measured.
- Oligotrophic
- 39 ft max depth
Willis Lake in Orange County, Florida has water-quality measurements published by Florida DEP, shown here as reported. Water clarity: 7.2 ft visibility. Phosphorus: 6 µg/L.
Willis Lake is a cold, clear oligotrophic lake in Orange County, Florida with an estimated average depth of about 39 feet. Water clarity is improving over recent sampling years. Compared to the 319 other monitored lakes in Orange County, Willis Lake ranks #121 for water quality.
Source: EPA Water Quality Portal sampling records, FDEP, last sampled 2025-02-17. 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, Willis Lake never exceeded the EPA safe-swimming threshold (235 MPN/100mL) — on 0% of 29 samples across 8 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 Willis Lake 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 Willis Lake
These are the measurements Florida DEP publishes for Willis Lake, 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 7.2 ft. Phosphorus 6 µg/L. TSI 39.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 7.2ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 6µg/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. | 39 | Oligotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Low nutrients, clear water. No reading is a swimming clearance.
Ask about Willis Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Willis Lake typically sits around 80°F at the surface in October. Summer average is about 88°F. Usually warmest in Jun (about 88°F) and coldest in Feb (about 69°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (69°F) to its warmest (88°F).
Typical surface water temperature by month, from 54 field readings (2010–2025) via the EPA Water Quality Portal. See the full Willis Lake water temperature breakdown →
Lake Details
Max depth
~39 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 Willis Lake.
Lake Size & Watershed
Watershed (drainage) area
1 sq mi
HydroLAKES / HydroSHEDS
Surface area
111 acres
HydroLAKES / HydroSHEDS
Shoreline
1.6 mi
HydroLAKES / HydroSHEDS
Elevation
102 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 Willis Lake
Compare lakeside cabins, hotels, and vacation rentals near Willis Lake in Orange 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 Willis Lake
Prices for Oct 16–18, 4 adults. Change dates on the map below.
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Fishing Willis Lake
Water Quality Trend: Stable
Based on 5 years of monitoring (2020–2024).
Water clarity
Improving5 years
Phosphorus
Worsening+1.8 µg/L/yr5 years
Regulated Pollution Sources Nearby
2 EPA-permitted facilities operate within about 5 miles of Willis Lake under Clean Water Act (NPDES) discharge permits. 1 facility has a reported Clean Water Act violation in the past three years.
- Sea WorldOrlando · 1.2 mi away · NPDES FL0629332Recent violation
- Discovery CoveOrlando · 1.2 mi away · NPDES FL0622648
Facilities permitted to discharge under the Clean Water Act within ~5 miles; proximity does not by itself mean a facility affects this lake. Source: EPA ECHO (ICIS-NPDES), as of 2026-07.
Nearby Lakes in Orange County
Frequently asked questions about Willis Lake
Where is Willis Lake?
- Willis Lake is a lake in Orange County, Florida. Its water-quality measurements are published by Florida DEP and shown on this page as reported.
What is the water quality of Willis Lake?
- Willis Lake in Orange County, Florida has water-quality measurements published by Florida DEP, shown here as reported. Water clarity: 7.2 ft visibility. Phosphorus: 6 µg/L.
Is Willis Lake safe to swim in?
- Based on E. coli testing, Willis Lake never exceeded the EPA safe-swimming threshold (235 MPN/100mL) — on 0% of 29 samples across 8 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 Willis Lake 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 Willis Lake?
- Willis Lake typically sits around 80°F at the surface in October, from 54 EPA Water Quality Portal field readings (2010–2025). That is a typical value for the month, not a live reading.
How deep is Willis Lake?
- No published bathymetric survey covers Willis Lake, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 39 feet, but that is a modelled estimate derived from surrounding terrain rather than a measurement on the water, so treat it as approximate.
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Where this data comes from
63 measurements from 1 monitoring station, 2020–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Submitting organization not recorded for these samples63 samples · 2020–2025
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
Regulated discharger data from EPA ECHO (ICIS-NPDES)
Lake size & watershed from HydroLAKES (HydroSHEDS)