Koosharem Reservoir is a productive, nutrient-rich eutrophic lake in Sevier County, Utah. Water quality is graded D based on 2 sampling years through 2020. Compared to the 12 other monitored lakes in Sevier County, Koosharem Reservoir ranks #9 for water quality.
Source: EPA Water Quality Portal sampling records, Utah DNR, last sampled 2020-08-26. Grade methodology: LakeGrade methodology.
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Swimming Safety
Swimming not recommended, poor water quality with high algae risk
Water Quality Grade: D, Poor
Moderate clarity, visible to about 7.2 ft. Chlorophyll-a: 58.4 µg/L. Trophic State Index: 60.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 7.2 ft | C |
| Phosphorus | No data | |
| Chlorophyll-a (Algae) | 58.4 µg/L | F |
| Trophic State Index (TSI) | 60 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Where to stay near Koosharem Reservoir
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Fishing Koosharem Reservoir
Location
County Ranking
Ranked #9 of 13 lakes in Sevier County
Cleaner Lakes Within 30 Miles
Koosharem Reservoir holds Grade D. One nearby lake has a higher grade.
See full comparison →Nearby Lakes in Sevier County
Explore Koosharem Reservoir across LakeGrade
More Utah Lake Rankings
Other Grade D Lakes in Utah
Wayne County · Clarity: 5.9 ft
Piute County · Clarity: 1 ft
Garfield County · Clarity: 1.5 ft
Garfield County · Clarity: 5.7 ft
Garfield County · Clarity: 1.5 ft
Garfield County · Clarity: 6.1 ft
Eutrophic Lakes in Utah
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: 2020-08-26
Monitoring stations: 1