Trtl Lake
Trtl Lake in Lake County, Florida has a water quality grade of D (Nutrient-rich). Water clarity: 1.8 ft visibility. Phosphorus: 81.2 µg/L.
- Clarity
- 1.8 ft
- Typical in August
- 88°F
- Type
- Eutrophic
- Trend
- → Stable
Grade D measures nutrients and algae, not whether this is a good place for a cabin trip. Cabins and rentals near Trtl Lake →
Next lake in Lake County
Swipe left or right on this bar to open the next or previous lake.
Trtl Lake is a productive, nutrient-rich eutrophic lake in Lake County, Florida. Water quality is graded D based on 1 sampling years through 2025. Compared to the 127 other monitored lakes in Lake County, Trtl Lake ranks #121 for water quality.
Source: EPA Water Quality Portal sampling records, FDEP, last sampled 2025-04-16. Grade methodology: LakeQuality methodology.
Watch Trtl Lake water quality
Subscribe for LakeQuality updates by email. No spam, unsubscribe anytime.
Swimming Safety
Grade onlyElevated nutrients
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)
Very murky, less than 1.8 ft of visibility. Phosphorus level: 81.2 µg/L. Trophic State Index: 68.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 1.8 ft | Not graded |
| Phosphorus | 81.2 µg/L | Poor |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 68 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Where to stay near Trtl Lake
Compare lakeside cabins, hotels, and vacation rentals near Trtl Lake in Lake 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 Trtl Lake are listed below.
Top-rated places to stay near Trtl 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 →
Water Temperature
Trtl Lake typically sits around 88°F at the surface in August. Summer average is about 87°F. Usually warmest in Aug (about 88°F) and coldest in Dec (about 61°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 128 field readings (2010–2025) via the EPA Water Quality Portal. See the full Trtl Lake water temperature breakdown →
Fishing Trtl Lake
Water Quality Trend: → Stable
Based on 6 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | → Stable | -0.005 m/yr | 6 |
| Phosphorus | → Stable | +0.29 µg/L/yr | 6 |
EPA Impairment Status
Trtl Lake is officially listed as impaired under Clean Water Act §303(d) in the 2022 EPA reporting cycle (IR category 5).
Causes of impairment
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit FL2819A · Official waterbody report · Matched by proximity (0.02 km)
County Ranking
Ranked #121 of 128 lakes in Lake County
Nearby Lakes With Higher Grades
Trtl Lake holds Grade D. One nearby lake has a higher nutrient-and-algae grade — useful for a swim day, not a reason to skip lodging here.
See full comparison →Nearby Lakes in Lake County
Frequently asked questions about Trtl Lake
Where is Trtl Lake?
- Trtl Lake is a lake in Lake County, Florida. LakeQuality grades it D for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for Trtl Lake?
- Trtl Lake in Lake County, Florida has a water quality grade of D (Nutrient-rich). Water clarity: 1.8 ft visibility. Phosphorus: 81.2 µg/L.
Is Trtl 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. Trtl Lake has a water quality grade of D (Nutrient-rich). Always check local health department advisories before swimming.
What is the water temperature of Trtl Lake?
- Trtl Lake typically sits around 88°F at the surface in August, from 128 EPA Water Quality Portal field readings (2010–2025). That is a typical value for the month, not a live reading.
Explore Trtl Lake across LakeQuality
More Florida Lake Rankings
Other Grade D Lakes in Florida
Eutrophic Lakes in Florida
Where this data comes from
96 measurements from 1 monitoring station, 2020–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- St. Johns River Water Management District
21FLSJWM_WQX96 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