Brannan Reservoir
Brannan Reservoir in Sweetwater County, Wyoming is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 99 acres.
- Area
- 99 acres
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Why Brannan Reservoir has no grade
We grade a lake only when the monitoring record supports a letter: at least three phosphorus or chlorophyll-a samples in the last ten years, scored against EPA National Lakes Assessment thresholds for this lake’s ecoregion. For Brannan Reservoir, no water-quality sampling on record for this lake.
Not Rated is not an F. It is EPA Integrated Reporting Category 3 — insufficient information. The water here may be excellent or poor; nobody has measured enough of it to say. Everything below that has been measured is still reported on this page.
Sampling is run by Wyoming DEQ and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Brannan Reservoir is a 99-acre lake in Sweetwater County, Wyoming.
Source: EPA Water Quality Portal sampling records, Wyoming DEQ, last sampled recent years. Grade methodology: LakeQuality methodology.
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Swimming Safety
Not ratedElevated nutrients
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for Brannan Reservoir
These readings exist but are not enough for an A–F grade — see why.
No clarity data. Trophic State Index: undefined.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | No recent samples | |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) |
Where to stay near Brannan Reservoir
Compare lakeside cabins, hotels, and vacation rentals near Brannan Reservoir in Sweetwater County, Wyoming — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water.
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 99 acres |
No bathymetric survey has been published for Brannan Reservoir, so its depth is not documented here.
Fishing Brannan Reservoir
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Frequently asked questions about Brannan Reservoir
Where is Brannan Reservoir?
- Brannan Reservoir is a lake in Sweetwater County, Wyoming. LakeQuality has not rated this lake (UNRATED) — no water-quality sampling on record for this lake.
What is the water quality grade for Brannan Reservoir?
- Brannan Reservoir in Sweetwater County, Wyoming is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 99 acres.
Is Brannan Reservoir safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Brannan Reservoir is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
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Where this data comes from
Measurements for Brannan Reservoir come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.