Lake Koocanusa is a cold, clear oligotrophic lake in Lincoln County, Montana. Water quality is graded B based on 1 sampling years through 2018. Compared to the 25 other monitored lakes in Lincoln County, Lake Koocanusa ranks #26 for water quality.
Source: EPA Water Quality Portal sampling records, Montana DNR, last sampled 2018-10-23. Grade methodology: LakeGrade methodology.
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Swimming Safety
Good for swimming, clear water with low algae levels
Water Quality Grade: B, Good
Good clarity, visible to about 14.8 ft. Trophic State Index: 38.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 14.8 ft | B |
| Phosphorus | No data | |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 38 | Oligotrophic |
Low nutrients, clear water, excellent for swimming
Where to stay near Lake Koocanusa
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Fishing Lake Koocanusa
Location
County Ranking
Ranked #26 of 26 lakes in Lincoln County
Cleaner Lakes Within 30 Miles
Lake Koocanusa holds Grade B. 2 nearby lakes hold higher grades.
Nearby Lakes in Lincoln County
Explore Lake Koocanusa across LakeGrade
More Montana Lake Rankings
Other Grade B Lakes in Montana
Oligotrophic Lakes in Montana
More records, surveys & data sources
Data Sources
Water quality data from the EPA Water Quality Portal
Grading methodology based on Metropolitan Council standards
Most recent sample: 2018-10-23
Monitoring stations: 1