Upper New Fork Lake
Sublette County, WyomingView mapDirections
Clarity, phosphorus, and algae sit in the clean band for this region.
- Mesotrophic
- #5 of 8 in the county
- Limited data
Upper New Fork Lake in Sublette County, Wyoming has a water quality grade of B (Good). Water clarity: 10.5 ft visibility. Phosphorus: 10 µg/L.
- Clarity
- 10.5 ft
- Type
- Mesotrophic
- Phosphorus
- 10 µg/L
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Watch Upper New Fork Lake’s letter
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Upper New Fork Lake is a mesotrophic lake in Sublette County, Wyoming. Water quality is graded B based on 1 sampling years through 2019. Compared to the 7 other monitored lakes in Sublette County, Upper New Fork Lake ranks #5 for water quality.
Source: EPA Water Quality Portal sampling records, Wyoming DEQ, last sampled 2019-09-09. Grade methodology: LakeQuality methodology.
What Upper New Fork Lake is good for
From access and monitoring records, not editorial picks.
- Clear water10.5 ft of visibility
Swimming Safety
Grade onlyLimited data
Based on clarity and algae grades from past sampling — we do not hold live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
The B is nutrients and algae, not a swimming clearance. Check local advisories before you swim.
Water Quality Grade: B (Good)
Good clarity, visible to about 10.5 ft. Phosphorus 10 µg/L. TSI 40. The letter is not a swimming clearance.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 10.5 ft | Not graded |
| Phosphorus | 10 µg/L | Good |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 40 | Mesotrophic |
Moderate nutrients, good water quality
Fishing Upper New Fork Lake
County Ranking
Ranked #5 of 8 lakes in Sublette County
Nearby Lakes in Sublette County
Frequently asked questions about Upper New Fork Lake
Where is Upper New Fork Lake?
- Upper New Fork Lake is a lake in Sublette County, Wyoming. LakeQuality grades it B for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for Upper New Fork Lake?
- Upper New Fork Lake in Sublette County, Wyoming has a water quality grade of B (Good). Water clarity: 10.5 ft visibility. Phosphorus: 10 µg/L.
Is Upper New Fork Lake safe to swim in?
- The B is nutrients and algae, not a swimming clearance. Check local advisories before you swim.
Explore Upper New Fork Lake across LakeQuality
13.1 mi away · recorded at 86°F
Species activity outlook by water temperature and season
Where to stay at Wyoming's top lakes, each with its grade
Moderate nutrients, good water quality
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Where this data comes from
12 measurements from 2 monitoring stations, 2019. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- State of Wyoming Department of Environmental Quality Watershed Program
WYDEQ_WATERSHED12 samples · 2019
Analytical methods
- Secchi
- Total Phosphorus After Block Digestion
Monitoring station identifiers (2)
Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See how grades are calculated and data sources.