Frontenac County, Ontario · Water Quality Report Card
Cole Lake
Cole Lake in Frontenac, Ontario received a water quality grade of B (Good). Water clarity: 1.8 m visibility. Phosphorus: 18.5 µg/L.
- Clarity
- 1.8 m
- Type
- Mesotrophic
Cole Lake is a mesotrophic lake in Frontenac County, Ontario. Water quality is graded B based on 2 sampling years through 2025. Compared to the 106 other monitored lakes in Frontenac County, Cole Lake ranks #101 for water quality.
Source: EPA Water Quality Portal sampling records, Ontario MECP, last sampled 2025-06-23. 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: 18.5 µg/L. Trophic State Index: 49.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 1.8 m | D |
| Phosphorus | 18.5 µg/L | A |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 49 | Mesotrophic |
Moderate nutrients, good water quality
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Fishing Cole Lake
Location
County Ranking
Ranked #101 of 107 lakes in Frontenac
Cleaner Lakes Within 30 Miles
Cole Lake holds Grade B. 5 nearby lakes hold higher grades.
- AThirteen Island LakeFrontenac · 3.6 mi · Higher grade (B → A)
- AThirty Island LakeFrontenac · 3.8 mi · Higher grade (B → A)
- ASt Andrews LakeFrontenac · 2.5 mi · Higher grade (B → A)
- ASt Andrew LakesFrontenac · 2.7 mi · Higher grade (B → A)
- AElbow LakeFrontenac · 4.5 mi · Higher grade (B → A)
Nearby Lakes in Frontenac
Explore Cole 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 Cole 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: 2025-06-23
Monitoring stations: