Frontenac County, Ontario · Water Quality Report Card
Rock Lake
Rock Lake in Frontenac, Ontario received a water quality grade of B (Good). Water clarity: 1.8 m visibility. Phosphorus: 12.6 µg/L.
- Clarity
- 1.8 m
- Type
- Mesotrophic
Rock Lake is a mesotrophic lake in Frontenac County, Ontario. Water quality is graded B based on 2 sampling years through 2023. Compared to the 106 other monitored lakes in Frontenac County, Rock Lake ranks #103 for water quality.
Source: EPA Water Quality Portal sampling records, Ontario MECP, last sampled 2023-05-17. Grade methodology: LakeGrade methodology.
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Swimming Safety
Good for swimming, clear water with low algae levels
Water Quality Grade: B, Good
Murky, only visible to about 5.9 ft. Phosphorus level: 12.6 µg/L. Trophic State Index: 46.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 1.8 m | D |
| Phosphorus | 12.6 µg/L | A |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 46 | Mesotrophic |
Moderate nutrients, good water quality
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Fishing Rock Lake
Location
County Ranking
Ranked #103 of 107 lakes in Frontenac
Cleaner Lakes Within 30 Miles
Rock Lake holds Grade B. 5 nearby lakes hold higher grades.
- APine LakeFrontenac · 4.9 mi · Higher grade (B → A)
- ABig Clear LakeFrontenac · 6.3 mi · Higher grade (B → A)
- ABig Gull LakeFrontenac · 4.7 mi · Higher grade (B → A)
- BHungry LakeFrontenac · 0.9 mi · Higher overall water quality score
- BMink LakeFrontenac · 1.2 mi · Higher overall water quality score
Nearby Lakes in Frontenac
Explore Rock Lake across LakeGrade
More Ontario Lake Rankings
Other Grade B Lakes in Ontario
Mesotrophic Lakes in Ontario
More records, surveys & data sources
Where this data comes from
Measurements for Rock Lake come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.
Data Sources
Water quality data from the EPA Water Quality Portal
Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion
Most recent sample: 2023-05-17
Monitoring stations: