Nan Lake
Orange County, FloridaView mapDirections
Florida DEP publishes the water-quality measurements for Nan Lake. Here is what has been measured.
- Mesotrophic
- Impaired · Impaired biota (cause unknown)
Nan Lake in Orange County, Florida has water-quality measurements published by Florida DEP, shown here as reported. Water clarity: 5.1 ft visibility. Phosphorus: 13 µg/L.
Nan Lake is a mesotrophic lake in Orange County, Florida. Overall water quality is declining over recent sampling years. Compared to the 319 other monitored lakes in Orange County, Nan Lake ranks #119 for water quality.
Source: EPA Water Quality Portal sampling records, FDEP, last sampled 2025-01-15. 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, Nan Lake never exceeded the EPA safe-swimming threshold (235 MPN/100mL) — on 0% of 31 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 Nan 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 Nan Lake
These are the measurements Florida DEP publishes for Nan Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Murky, only visible to about 5.1 ft. Phosphorus 13 µg/L. TSI 47.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 5.1ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 13µg/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. | 47 | Mesotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Moderate nutrients, good water quality
Ask about Nan Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Nan Lake typically sits around 78°F at the surface in October. Summer average is about 87°F. Usually warmest in Jul (about 88°F) and coldest in Jan (about 62°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (62°F) to its warmest (88°F).
Typical surface water temperature by month, from 55 field readings (2010–2025) via the EPA Water Quality Portal. See the full Nan Lake water temperature breakdown →
Stays via Stay22
Stays near Nan Lake
Compare lakeside cabins, hotels, and vacation rentals near Nan 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 Nan Lake
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 Nan Lake
Water Quality Trend: Worsening
Based on 5 years of monitoring (2020–2024).
Water clarity
Stable5 years
Phosphorus
Worsening+1.3 µg/L/yr5 years
EPA Impairment Status
Nan Lake 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.
Source: EPA ATTAINS assessment unit FL3009H · Official waterbody report
Nearby Lakes in Orange County
Frequently asked questions about Nan Lake
Where is Nan Lake?
- Nan 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 Nan Lake?
- Nan Lake in Orange County, Florida has water-quality measurements published by Florida DEP, shown here as reported. Water clarity: 5.1 ft visibility. Phosphorus: 13 µg/L.
Is Nan Lake safe to swim in?
- Based on E. coli testing, Nan Lake never exceeded the EPA safe-swimming threshold (235 MPN/100mL) — on 0% of 31 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 Nan 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 Nan Lake?
- Nan Lake typically sits around 78°F at the surface in October, from 55 EPA Water Quality Portal field readings (2010–2025). That is a typical value for the month, not a live reading.
Explore Nan Lake across LakeQuality
Planning a trip around Canaveral?
Nan Lake is about 34 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
Mesotrophic Lakes in Florida
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
Impairment status from EPA ATTAINS 303(d) database