Boysen Reservoir is a productive, nutrient-rich eutrophic lake in Fremont County, Wyoming. Water quality is graded D based on 2 sampling years through 2023. Compared to the 36 other monitored lakes in Fremont County, Boysen Reservoir ranks #22 for water quality.
Source: EPA Water Quality Portal sampling records, Wyoming DNR, last sampled 2023-10-10. 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
Very murky, less than 2.5 ft of visibility. Phosphorus level: 35 µg/L. Trophic State Index: 60.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 2.5 ft | F |
| Phosphorus | 35 µg/L | C |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 60 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Where to stay near Boysen Reservoir
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Fishing Boysen Reservoir
Location
County Ranking
Ranked #22 of 37 lakes in Fremont County
Cleaner Lakes Within 30 Miles
Boysen Reservoir holds Grade D. 5 nearby lakes hold higher grades.
- BLake CameahwaitFremont County · 4.6 mi · Two grade letters higher (D → B)
- BBoysen Reservoir Transitional EmbaymentFremont County · 6.7 mi · Two grade letters higher (D → B)
- BBoysen ReservoirFremont County · 8.1 mi · Two grade letters higher (D → B)
- BBoysen ReservoirFremont County · 11.1 mi · Two grade letters higher (D → B)
- CBoysen ReservoirFremont County · 3.6 mi · Higher grade (D → C)
Nearby Lakes in Fremont County
Explore Boysen Reservoir across LakeGrade
More Wyoming Lake Rankings
Other Grade D Lakes in Wyoming
Eutrophic Lakes in Wyoming
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: 2023-10-10
Monitoring stations: 1