Lanark County, Ontario · Water Quality Report Card
Long Lake
Long Lake in Lanark, Ontario received a water quality grade of A (Excellent). Water clarity: 4.1 m visibility. Phosphorus: 8.8 µg/L.
- Clarity
- 4.1 m
- Type
- Oligotrophic
Long Lake is a cold, clear oligotrophic lake in Lanark County, Ontario. Water quality is graded A based on 2 sampling years through 2016. Compared to the 28 other monitored lakes in Lanark County, Long Lake ranks #19 for water quality.
Source: EPA Water Quality Portal sampling records, Ontario MECP, last sampled 2016-05-19. 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 13.5 ft. Phosphorus level: 8.8 µg/L. Trophic State Index: 38.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 4.1 m | B |
| Phosphorus | 8.8 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 #19 of 29 lakes in Lanark
Nearby Lakes in Lanark
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: 2016-05-19
Monitoring stations: