Reservoir · Wyoming · United States · BOR RISE
Gray Reef Reservoir
Gray Reef Reservoir and Dam
68.2% full
Capacity
2.23 hm³
Volume stored
2 hm³
Vs month average
85% of normal
Coordinates
42.566°N, 106.699°W
Last updated
2026-10-13
Current fill
68.2%vs 7 days ago
-16.6%losing
vs 1 year ago
-13.0%year-over-year
7-day trend
↓falling
Drought context
Storage vs October average
85%of normal
68.2% full on 2026-10-13, against an average of 79.8% for October across 6 years of readings (-11.6 points).
Drought Monitor at this site · 13 October 2026
D2severe drought
The ground at Gray Reef Reservoir's coordinates falls inside the D2 area of the weekly U.S. Drought Monitor map. That describes local conditions — rainfall, soil moisture, streamflow — not the reservoir's storage. Wyoming drought figures →
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: 2026-10-13.
Catchment Weather
Past 30 days + 14-day forecast · Open-Meteo
Satellite imagery: Esri, Maxar, Earthstar Geographics. Map: Esri, HERE, Garmin, © OpenStreetMap contributors. 42.566, -106.699 · Open in Google Maps
About Gray Reef Reservoir
As of October 13, 2026, Gray Reef Reservoir is filled to 68.2% of its total capacity, holding roughly 2 hm³ of water out of a maximum 2 hm³. At this level the reservoir is within its normal operating range.
Over the most recent week on record the fill level has fallen by 16.6 percentage points, and it is 13.0 points below its level on the same date a year earlier.
Across the readings we hold for Gray Reef Reservoir — 1824 data points between October 16, 2021 and October 13, 2026 — the level has ranged from a low of 9.0% (March 2, 2026) to a high of 102.7% (March 27, 2023). On average the reservoir is fullest around April and at its lowest around February.
It is operated by BOR primarily for multiple purposes. It lies within the Wyoming basin at 42.566°N, 106.699°W.
Key facts
- Current fill level
- 68.2%
- Water stored
- 2 hm³
- Total capacity
- 2 hm³
- 7-day change
- ▼ 16.6 pts
- Year-on-year
- ▼ 13.0 pts
- Primary use
- Multipurpose
- River basin
- Wyoming
- Operator
- BOR
- Coordinates
- 42.566°N, 106.699°W
- Last updated
- October 13, 2026
Recent readings
| Date | Fill level | Volume (hm³) |
|---|---|---|
| 13 Oct 2026 | 68.2% | 2 |
| 12 Oct 2026 | 78.0% | 2 |
| 11 Oct 2026 | 74.4% | 2 |
| 10 Oct 2026 | 78.0% | 2 |
| 9 Oct 2026 | 81.6% | 2 |
| 8 Oct 2026 | 84.3% | 2 |
| 7 Oct 2026 | 83.9% | 2 |
| 6 Oct 2026 | 84.8% | 2 |
| 5 Oct 2026 | 85.7% | 2 |
| 4 Oct 2026 | 86.5% | 2 |
| 3 Oct 2026 | 87.9% | 2 |
| 2 Oct 2026 | 87.9% | 2 |