Round Lake
Pinellas County, FloridaHypereutrophic
Round Lake is a highly nutrient-loaded hypereutrophic lake in Pinellas County, Florida. Water quality is graded F based on 2 sampling years through 2021. Compared to the 54 other monitored lakes in Pinellas County, Round Lake ranks #42 for water quality.
Source: EPA Water Quality Portal sampling records, Florida DNR, last sampled 2021-02-17. Grade methodology: LakeGrade methodology.
Watch Round Lake water quality
Subscribe for LakeQuality updates by email. No spam, unsubscribe anytime.
Swimming Safety
Avoid swimming, very poor water quality, potential algae toxins
Water Quality Grade: F, Very Poor
Very murky, less than 1.6 ft of visibility. Phosphorus level: 490 µg/L. Trophic State Index: 82.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 1.6 ft | F |
| Phosphorus | 490 µg/L | F |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 82 | Hypereutrophic |
Very high nutrients, dense algae, poor clarity
Location
County Ranking
Ranked #42 of 55 lakes in Pinellas County
Cleaner Lakes Within 30 Miles
Round Lake holds Grade F. 5 nearby lakes hold higher grades.
- BPinellas-Hewitt LakePinellas County · 4.6 mi · Two grade letters higher (F → B)
- DPinellas-Crescent LakePinellas County · 0.6 mi · Higher grade (F → D)
- DHarbor Isles LakePinellas County · 4.4 mi · Higher grade (F → D)
- DPinellas-Harbor-Isle LakePinellas County · 4.4 mi · Higher grade (F → D)
- DLake DisstonPinellas County · 4.8 mi · Higher grade (F → D)
Nearby Lakes in Pinellas County
More Florida Lake Rankings
Other Grade F Lakes in Florida
Hypereutrophic Lakes in Florida
Regulated Pollution Sources Nearby
1 EPA-permitted facility operate within about 5 miles of Round Lake under Clean Water Act (NPDES) discharge permits, including 1 classified by the EPA as major discharger.
- St Petersburg - MS4Saint Petersburg · 0.7 mi away · NPDES FLS000007Major
Facilities permitted to discharge under the Clean Water Act within ~5 miles; proximity does not by itself mean a facility affects this lake. Source: EPA ECHO (ICIS-NPDES), as of 2026-07.
Data Sources
Water quality data from the EPA Water Quality Portal
Regulated discharger data from EPA ECHO (ICIS-NPDES)
Grading methodology based on Metropolitan Council standards
Most recent sample: 2021-02-17
Monitoring stations: 1
Where to stay near Round Lake
Compare lakeside cabins, hotels, and vacation rentals near Round Lake in Pinellas County, Florida — live availability and prices for your trip.
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.