Frontenac County, Ontario · Water Quality Report Card
Little John Lake
Little John Lake in Frontenac, Ontario received a water quality grade of A (Excellent). Water clarity: 4.4 m visibility. Phosphorus: 19.2 µg/L.
- Clarity
- 4.4 m
- Type
- Mesotrophic
Little John Lake is a mesotrophic lake in Frontenac County, Ontario. Water quality is graded A based on 2 sampling years through 2010. Compared to the 106 other monitored lakes in Frontenac County, Little John Lake ranks #83 for water quality.
Source: EPA Water Quality Portal sampling records, Ontario MECP, last sampled 2010-04-29. Grade methodology: LakeGrade methodology.
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Swimming Safety
Excellent for swimming, crystal clear water with minimal algae
Water Quality Grade: A, Excellent
Good clarity, visible to about 14.4 ft. Phosphorus level: 19.2 µg/L. Trophic State Index: 43.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 4.4 m | B |
| Phosphorus | 19.2 µg/L | A |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 43 | Mesotrophic |
Moderate nutrients, good water quality
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Fishing Little John Lake
Location
County Ranking
Ranked #83 of 107 lakes in Frontenac
Nearby Lakes in Frontenac
Explore Little John Lake across LakeGrade
More Ontario Lake Rankings
Other Grade A Lakes in Ontario
Mesotrophic Lakes in Ontario
More records, surveys & data sources
Where this data comes from
Measurements for Little John 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: 2010-04-29
Monitoring stations: