Seminole-Rock Lake
Seminole-Rock Lake in Seminole County, Florida has a water quality grade of B (Good). Water clarity: 5 ft visibility. Phosphorus: 12 µg/L.
- Clarity
- 5 ft
- Type
- Mesotrophic
- Trend
- ↓ Declining
Next lake in Seminole County
Swipe left or right on this bar to open the next or previous lake.
Seminole-Rock Lake is a mesotrophic lake in Seminole County, Florida. Water quality is graded B based on 1 sampling years through 2025. Overall water quality is declining over recent sampling years. Compared to the 121 other monitored lakes in Seminole County, Seminole-Rock Lake ranks #39 for water quality.
Source: EPA Water Quality Portal sampling records, FDEP, last sampled 2025-03-22. Grade methodology: LakeQuality methodology.
Watch Seminole-Rock Lake water quality
Subscribe for LakeQuality updates by email. No spam, unsubscribe anytime.
Swimming Safety
Grade onlyLow algae
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.
Good for swimming, clear water with low algae levels
Water Quality Grade: B (Good)
Murky, only visible to about 5 ft. Phosphorus level: 12 µg/L. Trophic State Index: 47.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 5 ft | Not graded |
| Phosphorus | 12 µg/L | Good |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 47 | Mesotrophic |
Moderate nutrients, good water quality
Where to stay near Seminole-Rock Lake
Compare lakeside cabins, hotels, and vacation rentals near Seminole-Rock 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 Seminole-Rock 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 Seminole-Rock Lake
Water Quality Trend: ↓ Declining
Based on 6 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↓ Declining | -0.554 m/yr | 6 |
| Phosphorus | → Stable | -0.15 µg/L/yr | 5 |
EPA Impairment Status
Seminole-Rock 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 FL2986E · Official waterbody report · Matched by proximity (1.11 km)
County Ranking
Ranked #39 of 122 lakes in Seminole County
Nearby Lakes in Seminole County
Frequently asked questions about Seminole-Rock Lake
Where is Seminole-Rock Lake?
- Seminole-Rock Lake is a lake in Seminole County, Florida. LakeQuality grades it B for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for Seminole-Rock Lake?
- Seminole-Rock Lake in Seminole County, Florida has a water quality grade of B (Good). Water clarity: 5 ft visibility. Phosphorus: 12 µg/L.
Is Seminole-Rock Lake safe to swim in?
- Good for swimming, clear water with low algae levels. Seminole-Rock Lake has a water quality grade of B (Good). Always check local health department advisories before swimming.
Explore Seminole-Rock Lake across LakeQuality
Planning a trip around Canaveral?
Seminole-Rock Lake is about 38 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 Florida Lake Rankings
Other Grade B Lakes in Florida
Mesotrophic Lakes in Florida
Where this data comes from
345 measurements from 3 monitoring stations, 2020–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- FLORIDA LAKEWATCH
21FLKWAT_WQX345 samples · 2020–2025
Monitoring station identifiers (3)
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