Lanark County, Ontario · Water Quality Report Card
Rainbow Lake
Rainbow Lake in Lanark, Ontario received a water quality grade of B (Good). Water clarity: 2.8 m visibility. Phosphorus: 13.8 µg/L.
- Clarity
- 2.8 m
- Type
- Mesotrophic
Rainbow Lake is a mesotrophic lake in Lanark County, Ontario. Water quality is graded B based on 2 sampling years through 2016. Compared to the 28 other monitored lakes in Lanark County, Rainbow Lake ranks #28 for water quality.
Source: EPA Water Quality Portal sampling records, Ontario MECP, last sampled 2016-05-23. Grade methodology: LakeGrade methodology.
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Swimming Safety
Good for swimming, clear water with low algae levels
Water Quality Grade: B, Good
Moderate clarity, visible to about 9.2 ft. Phosphorus level: 13.8 µg/L. Trophic State Index: 44.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 2.8 m | C |
| Phosphorus | 13.8 µg/L | A |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 44 | Mesotrophic |
Moderate nutrients, good water quality
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Fishing Rainbow Lake
Location
County Ranking
Ranked #28 of 29 lakes in Lanark
Cleaner Lakes Within 30 Miles
Rainbow Lake holds Grade B. 5 nearby lakes hold higher grades.
- ASilver LakeFrontenac · 1.7 mi · Higher grade (B → A)
- ADavern LakeLanark · 4 mi · Higher grade (B → A)
- AFarren LakeLanark · 5.3 mi · Higher grade (B → A)
- AFarrell LakeLanark · 5.3 mi · Higher grade (B → A)
- AObrien LakeLanark · 5.7 mi · Higher grade (B → A)
Nearby Lakes in Lanark
Explore Rainbow Lake across LakeGrade
More Ontario Lake Rankings
Other Grade B Lakes in Ontario
Mesotrophic Lakes in Ontario
More records, surveys & data sources
Where this data comes from
Measurements for Rainbow 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: 2016-05-23
Monitoring stations: