Island Pk Reservoir is a productive, nutrient-rich eutrophic lake in Fremont County, Idaho. Water quality is graded C based on 3 sampling years through 2024. Compared to the 5 other monitored lakes in Fremont County, Island Pk Reservoir ranks #4 for water quality.
Source: EPA Water Quality Portal sampling records, Idaho DNR, last sampled 2024-05-21. Grade methodology: LakeGrade methodology.
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Swimming Safety
Generally safe for swimming, moderate water quality
Water Quality Grade: C, Fair
Very murky, less than 2.3 ft of visibility. Phosphorus level: 56 µg/L. Chlorophyll-a: 9.8 µg/L. Trophic State Index: 60.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 2.3 ft | F |
| Phosphorus | 56 µg/L | C |
| Chlorophyll-a (Algae) | 9.8 µg/L | B |
| Trophic State Index (TSI) | 60 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Where to stay near Island Pk Reservoir
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Fishing Island Pk Reservoir
Location
County Ranking
Ranked #4 of 6 lakes in Fremont County
Cleaner Lakes Within 30 Miles
Island Pk Reservoir holds Grade C. One nearby lake has a higher grade.
See full comparison →Nearby Lakes in Fremont County
Explore Island Pk Reservoir across LakeGrade
More Idaho Lake Rankings
Other Grade C Lakes in Idaho
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Eutrophic Lakes in Idaho
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: 2024-05-21
Monitoring stations: 1