Reservoir · Montana · United States · BOR RISE
Gibson Reservoir
Gibson Reservoir and Dam
5.8% full
Capacity
122.19 hm³
Volume stored
7 hm³
Vs month average
95% of normal
Coordinates
47.601°N, 112.762°W
Last updated
2026-10-27
Current fill
5.8%vs 7 days ago
-0.3 pplosing
vs 1 year ago
-0.4 ppyear-over-year
7-day trend
→stable
Drought context
Storage vs October average
95%of normal
5.8% full on 2026-10-27, against an average of 6.1% for October across 6 years of readings (-0.3 points).
Drought Monitor at this site · 20 October 2026
Nonenot in a drought category
Gibson Reservoir's coordinates fall outside every category on the weekly U.S. Drought Monitor map. That describes local conditions — rainfall, soil moisture, streamflow — not the reservoir's storage. Montana 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: 2026-10-27.
Catchment Weather
Past 30 days + 14-day forecast · Open-Meteo
Satellite imagery: Esri, Maxar, Earthstar Geographics. Map: Esri, HERE, Garmin, © OpenStreetMap contributors. 47.601°N, 112.762°W · Open in Google Maps
About Gibson Reservoir
As of October 27, 2026, Gibson Reservoir is filled to 5.8% of its total capacity, holding 7.12 hm³ of water out of a maximum 122.19 hm³. At this level the reservoir is critically low.
Over the most recent week on record the fill level has held broadly steady (-0.3 pp), and it sits close to where it was a year earlier.
Across the readings we hold for Gibson Reservoir — 2017 data points between October 29, 2021 and October 27, 2026 — the level has ranged from a low of 4.7% (February 14, 2025) to a high of 99.7% (June 21, 2022). On average the reservoir is fullest around June and at its lowest around October.
It is operated by BOR primarily for multiple purposes. It is at 47.601°N, 112.762°W.
Key facts
- Current fill level
- 5.8% of total capacity
- Water stored
- 7.12 hm³
- Total capacity
- 122.19 hm³
- 7-day change
- ▼ 0.3 pp
- Year-on-year
- ▼ 0.4 pp
- Primary use
- Multipurpose
- Operator
- BOR
- Coordinates
- 47.601°N, 112.762°W
- Last updated
- October 27, 2026
Recent readings
| Date | Fill level | Volume (hm³) |
|---|---|---|
| 27 Oct 2026 | 5.8% | 7.12 |
| 26 Oct 2026 | 5.9% | 7.16 |
| 25 Oct 2026 | 5.9% | 7.2 |
| 24 Oct 2026 | 5.9% | 7.23 |
| 23 Oct 2026 | 5.9% | 7.25 |
| 22 Oct 2026 | 5.9% | 7.26 |
| 21 Oct 2026 | 6.0% | 7.36 |
| 20 Oct 2026 | 6.1% | 7.5 |
| 19 Oct 2026 | 6.2% | 7.63 |
| 18 Oct 2026 | 6.4% | 7.76 |
| 17 Oct 2026 | 6.4% | 7.87 |
| 16 Oct 2026 | 6.6% | 8.01 |