Deep Lake
Seminole County, FloridaView mapDirections
Florida DEP publishes the water-quality measurements for Deep Lake. Here is what has been measured.
- Eutrophic
- Limited data
Deep Lake in Seminole County, Florida has water-quality measurements published by Florida DEP, shown here as reported. Water clarity: 6.9 ft visibility. Phosphorus: 44 µg/L.
Deep Lake is a productive, nutrient-rich eutrophic lake in Seminole County, Florida. Overall water quality is declining over recent sampling years. Compared to the 121 other monitored lakes in Seminole County, Deep Lake ranks #99 for water quality.
Source: EPA Water Quality Portal sampling records, FDEP, last sampled 2025-06-02. Methodology: how these readings are compared.
Swimming conditions
Readings onlyLimited data
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.
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Deep 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 Deep Lake
These are the measurements Florida DEP publishes for Deep 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 6.9 ft. Phosphorus 44 µg/L. TSI 54.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 6.9ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 44µg/L | Fair 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 Deep Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Deep Lake typically sits around 87°F at the surface in September. Summer average is about 86°F. Usually warmest in Sep (about 87°F) and coldest in Dec (about 71°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (71°F) to its warmest (87°F).
Typical surface water temperature by month, from 37 field readings (2015–2025) via the EPA Water Quality Portal. See the full Deep Lake water temperature breakdown →
Stays via Stay22
Stays near Deep Lake
Compare lakeside cabins, hotels, and vacation rentals near Deep Lake 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 Deep 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 Deep Lake
Water Quality Trend: Worsening
Based on 6 years of monitoring (2020–2025).
Water clarity
Worsening6 years
Phosphorus
Worsening+1.04 µg/L/yr6 years
Nearby Lakes in Seminole County
Frequently asked questions about Deep Lake
Where is Deep Lake?
- Deep Lake 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 Deep Lake?
- Deep Lake in Seminole County, Florida has water-quality measurements published by Florida DEP, shown here as reported. Water clarity: 6.9 ft visibility. Phosphorus: 44 µg/L.
Is Deep Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
What is the water temperature of Deep Lake?
- Deep Lake typically sits around 87°F at the surface in September, from 37 EPA Water Quality Portal field readings (2015–2025). That is a typical value for the month, not a live reading.
Explore Deep Lake across LakeQuality
Planning a trip around Canaveral?
Deep Lake is about 32 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
50 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 samples36 samples · 2020–2025
- Submitting organization not recorded for these samples14 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.