Hanna Reservoir
Carbon County, Wyoming4 acresView mapDirections
Wyoming DEQ publishes the water-quality measurements for Hanna Reservoir. Here is what has been measured.
- Oligotrophic
- Limited data
Ask about Hanna Reservoir
Answers come straight from the public measurements and survey records on this page.
Hanna Reservoir in Carbon County, Wyoming has water-quality measurements published by Wyoming DEQ, shown here as reported. Phosphorus: 10 µg/L. Surface area: 4 acres.
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Hanna Reservoir is a 4-acre cold, clear oligotrophic lake in Carbon County, Wyoming. Compared to the 9 other monitored lakes in Carbon County, Hanna Reservoir ranks #6 for water quality.
Source: EPA Water Quality Portal sampling records, Wyoming DEQ, last sampled 2017-09-18. Grade methodology: LakeQuality methodology.
Swimming conditions
Readings onlyLimited data
Based on clarity and algae readings from past sampling — there is no live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Hanna Reservoir is safe to swim in today is a call for the Wyoming Department of Environmental Quality and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Hanna Reservoir
These are the measurements Wyoming DEQ publishes for Hanna Reservoir, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
No clarity data. Phosphorus 10 µg/L. TSI 37.
| Metric | Value | EPA condition class |
|---|---|---|
| Water Clarity (Secchi Depth) | No recent samples | |
| Phosphorus | 10 µg/L | Good |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 37 | Oligotrophic |
Low nutrients, clear water. No reading is a swimming clearance.
Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 4 acres |
No bathymetric survey has been published for Hanna Reservoir, so its depth is not documented here.
Fishing Hanna Reservoir
Reservoir Info (USACE NID)
Hanna Reservoir is a man-made reservoir impounded by the Hanna (completed 1934), built primarily for other on the Rattlesnake Creek; concrete-type dam, 25 ft tall and 594 ft long.
- Surface area
- 4 ac
- Normal storage
- 62 ac-ft
- Max storage
- 0 ac-ft
- Drainage area
- 0 sq mi
- Hazard class
- Low
- Owner
- TOWN OF HANNA (RICHARD GREGORY)
All listed purposes: Other;Water Supply.
Source: USACE National Inventory of Dams, NID ID WY01683 · Operator website
Nearby Lakes in Carbon County
Frequently asked questions about Hanna Reservoir
Where is Hanna Reservoir?
- Hanna Reservoir is a lake in Carbon County, Wyoming. Its water-quality measurements are published by Wyoming DEQ and shown on this page as reported.
What is the water quality of Hanna Reservoir?
- Hanna Reservoir in Carbon County, Wyoming has water-quality measurements published by Wyoming DEQ, shown here as reported. Phosphorus: 10 µg/L. Surface area: 4 acres.
Is Hanna Reservoir safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Explore Hanna Reservoir across LakeQuality
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Other Lakes in Wyoming
Oligotrophic Lakes in Wyoming
Where this data comes from
3 measurements from 1 monitoring station, 2017. 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_WATERSHED3 samples · 2017
Analytical methods
- Total Phosphorus After Block Digestion
Monitoring station identifiers (1)
EPA condition classes from the National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See where the data comes from and data sources.