Southern Lake
Southern Lake in Lee County, Florida has a water quality grade of D (Nutrient-rich). Phosphorus: 100.5 µg/L.
- Type
- Hypereutrophic
- Trend
- ↑ Improving
Grade D measures nutrients and algae, not whether this is a good place for a cabin trip. Cabins and rentals near Southern Lake →
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Southern Lake is a highly nutrient-loaded hypereutrophic lake in Lee County, Florida. Water quality is graded D based on 1 sampling years through 2025. Overall water quality is improving over recent sampling years. Compared to the 73 other monitored lakes in Lee County, Southern Lake ranks #19 for water quality.
Source: EPA Water Quality Portal sampling records, FDEP, last sampled 2025-04-16. Grade methodology: LakeQuality methodology.
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Swimming Safety
Grade onlyLimited data
Based on clarity and algae grades from past sampling — we do not hold live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Nutrients and algae run higher than average — check local advisories before swimming, and skip the water if you see scum
Water Quality Grade: D (Nutrient-rich)
No clarity data. Phosphorus level: 100.5 µg/L. Trophic State Index: 71.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | No recent samples | |
| Phosphorus | 100.5 µg/L | Poor |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 71 | Hypereutrophic |
Very high nutrients, dense algae, poor clarity
Where to stay near Southern Lake
Compare lakeside cabins, hotels, and vacation rentals near Southern Lake in Lee 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. The water-quality grade measures nutrients and algae, not lodging — cabins and rentals around Southern Lake are listed below.
Top-rated places to stay near Southern Lake
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.
Planning a whole trip? See where to stay at Florida’s top lakes →
Fishing Southern Lake
Water Quality Trend: ↑ Improving
Based on 2 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Phosphorus | ↑ Improving | -59.5 µg/L/yr | 2 |
EPA Impairment Status
Southern Lake is officially listed as impaired under Clean Water Act §303(d) in the 2022 EPA reporting cycle (IR category 4A).
Causes of impairment
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit FL2092F1 · Official waterbody report · Matched by proximity (1.68 km)
County Ranking
Ranked #19 of 74 lakes in Lee County
Nearby Lakes in Lee County
Frequently asked questions about Southern Lake
Where is Southern Lake?
- Southern Lake is a lake in Lee County, Florida. LakeQuality grades it D for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for Southern Lake?
- Southern Lake in Lee County, Florida has a water quality grade of D (Nutrient-rich). Phosphorus: 100.5 µg/L.
Is Southern Lake safe to swim in?
- Nutrients and algae run higher than average — check local advisories before swimming, and skip the water if you see scum. Southern Lake has a water quality grade of D (Nutrient-rich). Always check local health department advisories before swimming.
Explore Southern Lake across LakeQuality
More Florida Lake Rankings
Other Grade D Lakes in Florida
Hypereutrophic Lakes in Florida
Where this data comes from
5 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 samples5 samples · 2020–2025
Monitoring station identifiers (1)
Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See how grades are calculated and data sources.
Other records on this page
Impairment status from EPA ATTAINS 303(d) database