Parry Sound District County, Ontario · Water Quality Report Card
Brennan Lake
Brennan Lake in Parry Sound District, Ontario received a water quality grade of B (Good). Water clarity: 2.9 m visibility. Phosphorus: 10.2 µg/L.
- Clarity
- 2.9 m
- Type
- Mesotrophic
Brennan Lake is a mesotrophic lake in Parry Sound District County, Ontario. Water quality is graded B based on 2 sampling years through 2024. Compared to the 230 other monitored lakes in Parry Sound District County, Brennan Lake ranks #142 for water quality.
Source: EPA Water Quality Portal sampling records, Ontario MECP, last sampled 2024-05-31. 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 9.5 ft. Phosphorus level: 10.2 µg/L. Trophic State Index: 41.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 2.9 m | C |
| Phosphorus | 10.2 µg/L | A |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 41 | Mesotrophic |
Moderate nutrients, good water quality
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Fishing Brennan Lake
Location
County Ranking
Ranked #142 of 231 lakes in Parry Sound District
Cleaner Lakes Within 30 Miles
Brennan Lake holds Grade B. 4 nearby lakes hold higher grades.
- AWindfall LakeParry Sound District · 1.3 mi · Higher grade (B → A)
- ARankin LakeParry Sound District · 1.8 mi · Higher grade (B → A)
- ALioness LakeParry Sound District · 1.1 mi · Higher grade (B → A)
- ABack LakeParry Sound District · 1.6 mi · Higher grade (B → A)
Nearby Lakes in Parry Sound District
Explore Brennan 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 Brennan 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: 2024-05-31
Monitoring stations: