Pontiac County, Ontario · Water Quality Report Card
Lac Coulonge Lake
Lac Coulonge Lake in Pontiac, Ontario received a water quality grade of D (Poor). Water clarity: 1.6 m visibility.
- Clarity
- 1.6 m
- Type
- Eutrophic
Lac Coulonge Lake is a productive, nutrient-rich eutrophic lake in Pontiac County, Ontario. Water quality is graded D based on 1 sampling years through 2019. Compared to the 3 other monitored lakes in Pontiac County, Lac Coulonge Lake ranks #4 for water quality.
Source: EPA Water Quality Portal sampling records, Ontario MECP, last sampled 2019-05-15. Grade methodology: LakeGrade methodology.
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Swimming Safety
Swimming not recommended, poor water quality with high algae risk
Water Quality Grade: D, Poor
Murky, only visible to about 5.2 ft. Trophic State Index: 53.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 1.6 m | D |
| Phosphorus | No data | |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 53 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Where to stay near Lac Coulonge Lake
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Fishing Lac Coulonge Lake
Location
County Ranking
Ranked #4 of 4 lakes in Pontiac
Cleaner Lakes Within 30 Miles
Lac Coulonge Lake holds Grade D. 5 nearby lakes hold higher grades.
- BLower Allumette LakePontiac · 8.6 mi · Two grade letters higher (D → B)
- BLower Allumette LakeRenfrew · 10.6 mi · Two grade letters higher (D → B)
- BLac du Rocher-Fendu LakePontiac · 16.4 mi · Two grade letters higher (D → B)
- BAllumette LakeRenfrew · 17.5 mi · Two grade letters higher (D → B)
- CMuskrat LakeRenfrew · 15.6 mi · Higher grade (D → C)
Nearby Lakes in Pontiac
Explore Lac Coulonge Lake across LakeGrade
More Ontario Lake Rankings
Other Grade D Lakes in Ontario
Eutrophic Lakes in Ontario
More records, surveys & data sources
Where this data comes from
Measurements for Lac Coulonge 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: 2019-05-15
Monitoring stations: