Muskoka District County, Ontario · Water Quality Report Card
Marion Lake
Marion Lake in Muskoka District, Ontario received a water quality grade of A (Excellent). Phosphorus: 13.8 µg/L.
- Type
- Mesotrophic
Marion Lake is a mesotrophic lake in Muskoka District County, Ontario. Water quality is graded A based on 1 sampling years through 2009. Compared to the 169 other monitored lakes in Muskoka District County, Marion Lake ranks #31 for water quality.
Source: EPA Water Quality Portal sampling records, Ontario MECP, last sampled 2009-06-08. Grade methodology: LakeGrade methodology.
Watch Marion Lake 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
No clarity data. Phosphorus level: 13.8 µg/L. Trophic State Index: 42.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | No data | |
| Phosphorus | 13.8 µg/L | A |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 42 | Mesotrophic |
Moderate nutrients, good water quality
Where to stay near Marion Lake
Compare lakeside cabins, hotels, and vacation rentals near Marion Lake in Muskoka District, Ontario — 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 Marion Lake
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 Marion Lake?
Get lake water-quality report cards plus the best cabin & lodging deals near Marion Lake — straight to your inbox. No spam, unsubscribe anytime.
Fishing Marion Lake
Location
County Ranking
Ranked #31 of 170 lakes in Muskoka District
Nearby Lakes in Muskoka District
Explore Marion 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 Marion 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: 2009-06-08
Monitoring stations: