Les Pays-d'en-Haut County, Québec · Water Quality Report Card
Lac Cornu
Lac Cornu in Les Pays-d'en-Haut, Québec received a water quality grade of A (Excellent). Water clarity: 3.3 m visibility. Phosphorus: 9.6 µg/L. Chlorophyll-a (algae): 4.4 µg/L.
- Clarity
- 3.3 m
- Type
- Mesotrophic
Lac Cornu is a mesotrophic lake in Les Pays-d'en-Haut County, Québec. Water quality is graded A based on 3 sampling years through 2025. Compared to the 108 other monitored lakes in Les Pays-d'en-Haut County, Lac Cornu ranks #54 for water quality.
Source: EPA Water Quality Portal sampling records, MELCCFP, last sampled 2025-08-01. Grade methodology: LakeGrade methodology.
Watch Lac Cornu water quality
Subscribe for LakeQuality updates by email. No spam, unsubscribe anytime.
Swimming Safety
Excellent for swimming, crystal clear water with minimal algae
Water Quality Grade: A, Excellent
Good clarity, visible to about 10.8 ft. Phosphorus level: 9.6 µg/L. Chlorophyll-a: 4.4 µg/L. Trophic State Index: 42.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 3.3 m | B |
| Phosphorus | 9.6 µg/L | A |
| Chlorophyll-a (Algae) | 4.4 µg/L | A |
| Trophic State Index (TSI) | 42 | Mesotrophic |
Moderate nutrients, good water quality
Where to stay near Lac Cornu
Compare lakeside cabins, hotels, and vacation rentals near Lac Cornu in Les Pays-d'en-Haut, Québec — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water.
Top-rated places to stay near Lac Cornu
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.
Planning a trip to Lac Cornu?
Get lake water-quality report cards plus the best cabin & lodging deals near Lac Cornu — straight to your inbox. No spam, unsubscribe anytime.
Fishing Lac Cornu
Location
County Ranking
Ranked #54 of 109 lakes in Les Pays-d'en-Haut
Nearby Lakes in Les Pays-d'en-Haut
Explore Lac Cornu across LakeGrade
More Québec Lake Rankings
Other Grade A Lakes in Québec
Mesotrophic Lakes in Québec
More records, surveys & data sources
Where this data comes from
Measurements for Lac Cornu 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: 2025-08-01
Monitoring stations: