Lake Arnold
Orange County, FloridaView mapDirections
Florida DEP publishes the water-quality measurements for Lake Arnold. Here is what has been measured.
- Eutrophic
- Impaired · Algal growth
Lake Arnold in Orange County, Florida has water-quality measurements published by Florida DEP, shown here as reported. Water clarity: 3.1 ft visibility. Phosphorus: 20.5 µg/L.
Lake Arnold is a productive, nutrient-rich eutrophic lake in Orange County, Florida. Overall water quality is improving over recent sampling years. Compared to the 319 other monitored lakes in Orange County, Lake Arnold ranks #150 for water quality.
Source: EPA Water Quality Portal sampling records, FDEP, last sampled 2025-04-24. Methodology: how these readings are compared.
Swimming conditions
Readings onlyRecreation use not supported
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 Arnold never exceeded the EPA safe-swimming threshold (235 MPN/100mL) — on 0% of 24 samples across 7 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 Arnold 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 Arnold
These are the measurements Florida DEP publishes for Lake Arnold, 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 3.1 ft of visibility. Phosphorus 20.5 µg/L. TSI 54.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 3.1ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 20.5µg/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. | 54 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Lake Arnold
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Lake Arnold typically sits around 81°F at the surface in September. Summer average is about 82°F. Usually warmest in Jul (about 88°F) and coldest in Jan (about 63°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (63°F) to its warmest (88°F).
Typical surface water temperature by month, from 193 field readings (2010–2025) via the EPA Water Quality Portal. See the full Lake Arnold water temperature breakdown →
Stays via Stay22
Stays near Lake Arnold
Compare lakeside cabins, hotels, and vacation rentals near Lake Arnold 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 Lake Arnold
Prices for Oct 16–18, 4 adults. Change dates on the map below.
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Fishing Lake Arnold
Water Quality Trend: Improving
Based on 5 years of monitoring (2020–2024).
Water clarity
Improving5 years
Phosphorus
Improving-5.95 µg/L/yr5 years
EPA Impairment Status
Lake Arnold is officially listed as impaired under Clean Water Act §303(d) in the 2022 EPA reporting cycle (IR category 5A).
Causes of impairment
Designated uses not supporting: Aquatic life, Recreation.
Source: EPA ATTAINS assessment unit FL3168Z3 · Official waterbody report
Nearby Lakes in Orange County
Frequently asked questions about Lake Arnold
Where is Lake Arnold?
- Lake Arnold 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 Lake Arnold?
- Lake Arnold in Orange County, Florida has water-quality measurements published by Florida DEP, shown here as reported. Water clarity: 3.1 ft visibility. Phosphorus: 20.5 µg/L.
Is Lake Arnold safe to swim in?
- Based on E. coli testing, Lake Arnold never exceeded the EPA safe-swimming threshold (235 MPN/100mL) — on 0% of 24 samples across 7 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 Arnold 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 Arnold?
- Lake Arnold typically sits around 81°F at the surface in September, from 193 EPA Water Quality Portal field readings (2010–2025). That is a typical value for the month, not a live reading.
Explore Lake Arnold across LakeQuality
Planning a trip around Canaveral?
Lake Arnold is about 40 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
61 measurements from 2 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 samples37 samples · 2020–2025
- Submitting organization not recorded for these samples24 samples · 2024–2025
Monitoring station identifiers (2)
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