Reservoir · Wyoming · United States · BOR RISE
Seminoe Reservoir
Seminoe Reservoir Dam and Powerplant
24.8% full
Capacity
1,254.8 hm³
Volume stored
311 hm³
Coordinates
42.156°N, 106.908°W
Last updated
2026-09-12
Current fill
24.8%vs 7 days ago
-0.9%losing
vs 1 year ago
-13.6%year-over-year
7-day trend
→stable
Data source: BOR RISE — US Bureau of Reclamation — daily reservoir storage volume. Capacity is the design (normal full-pool) capacity from the US National Inventory of Dams (NID); fill % = current volume ÷ design capacity. Last reading: 2026-09-12.
Catchment Weather
Past 30 days + 14-day forecast · Open-Meteo
Satellite imagery: Esri, Maxar, Earthstar Geographics. Map: Esri, HERE, Garmin, © OpenStreetMap contributors. 42.156, -106.908 · Open in Google Maps
About Seminoe Reservoir
As of September 12, 2026, Seminoe Reservoir is filled to 24.8% of its total capacity, holding roughly 311 hm³ of water out of a maximum 1,255 hm³. At this level the reservoir is low.
Over the most recent week on record the fill level has held broadly steady (-0.9 pts), and it is 13.6 points below its level on the same date a year earlier.
Across the readings we hold for Seminoe Reservoir — 1953 data points between September 15, 2021 and September 12, 2026 — the level has ranged from a low of 24.8% (September 12, 2026) to a high of 86.4% (June 28, 2023). On average the reservoir is fullest around June and at its lowest around February.
It is operated by BOR primarily for multiple purposes. It lies within the Wyoming basin at 42.156°N, 106.908°W.
Key facts
- Current fill level
- 24.8%
- Water stored
- 311 hm³
- Total capacity
- 1,255 hm³
- 7-day change
- ▼ 0.9 pts
- Year-on-year
- ▼ 13.6 pts
- Primary use
- Multipurpose
- River basin
- Wyoming
- Operator
- BOR
- Coordinates
- 42.156°N, 106.908°W
- Last updated
- September 12, 2026
Recent readings
| Date | Fill level | Volume (hm³) |
|---|---|---|
| 12 Sep 2026 | 24.8% | 311 |
| 11 Sep 2026 | 24.9% | 312 |
| 10 Sep 2026 | 25.1% | 315 |
| 9 Sep 2026 | 25.2% | 317 |
| 8 Sep 2026 | 25.4% | 318 |
| 7 Sep 2026 | 25.5% | 320 |
| 6 Sep 2026 | 25.6% | 321 |
| 5 Sep 2026 | 25.7% | 322 |
| 4 Sep 2026 | 25.8% | 324 |
| 3 Sep 2026 | 25.9% | 325 |
| 2 Sep 2026 | 26.0% | 327 |
| 1 Sep 2026 | 26.1% | 328 |