Thunder Bay District County, Ontario · Water Quality Report Card
Long Lake
Long Lake in Thunder Bay District, Ontario received a water quality grade of A (Excellent). Water clarity: 3.1 m visibility. Phosphorus: 7 µg/L.
- Clarity
- 3.1 m
- Type
- Oligotrophic
Long Lake is a cold, clear oligotrophic lake in Thunder Bay District County, Ontario. Water quality is graded A based on 2 sampling years through 2023. Compared to the 301 other monitored lakes in Thunder Bay District County, Long Lake ranks #101 for water quality.
Source: EPA Water Quality Portal sampling records, Ontario MECP, last sampled 2023-08-01. 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 10.2 ft. Phosphorus level: 7 µg/L. Trophic State Index: 38.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 3.1 m | B |
| Phosphorus | 7 µg/L | A |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 38 | Oligotrophic |
Low nutrients, clear water, excellent for swimming
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Fishing Long Lake
Location
County Ranking
Ranked #101 of 302 lakes in Thunder Bay District
Nearby Lakes in Thunder Bay District
Explore Long Lake across LakeGrade
More Ontario Lake Rankings
Other Grade A Lakes in Ontario
Oligotrophic Lakes in Ontario
More records, surveys & data sources
Where this data comes from
Measurements for Long 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: 2023-08-01
Monitoring stations: