Reservoir · Montana · United States · BOR RISE
Willow Creek Reservoir
Willow Creek Reservoir and Dam (MT)
54.3% full
Capacity
39.84 hm³
Volume stored
22 hm³
Vs month average
182% of normal
Coordinates
47.547°N, 112.429°W
Last updated
2026-10-28
Current fill
54.3%vs 7 days ago
+3.4 ppgaining
vs 1 year ago
+41.5 ppyear-over-year
7-day trend
↑rising
Drought context
Storage vs October average
182%of normal
54.3% full on 2026-10-28, against an average of 29.9% for October across 6 years of readings (+24.4 points).
Drought Monitor at this site · 27 October 2026
Nonenot in a drought category
Willow Creek 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: 2026-10-28.
Catchment Weather
Past 30 days + 14-day forecast · Open-Meteo
Satellite imagery: Esri, Maxar, Earthstar Geographics. Map: Esri, HERE, Garmin, © OpenStreetMap contributors. 47.547°N, 112.429°W · Open in Google Maps
About Willow Creek Reservoir
As of October 28, 2026, Willow Creek Reservoir is filled to 54.3% of its total capacity, holding 21.65 hm³ of water out of a maximum 39.84 hm³. At this level the reservoir is within its normal operating range.
Over the most recent week on record the fill level has risen by 3.4 percentage points, and it is 41.5 points above its level on the same date a year earlier.
Across the readings we hold for Willow Creek Reservoir — 2038 data points between October 30, 2021 and October 28, 2026 — the level has ranged from a low of 12.5% (November 21, 2025) to a high of 93.8% (May 29, 2022). On average the reservoir is fullest around June and at its lowest around September.
It is operated by BOR primarily for multiple purposes. It is at 47.547°N, 112.429°W.
Key facts
- Current fill level
- 54.3% of total capacity
- Water stored
- 21.65 hm³
- Total capacity
- 39.84 hm³
- 7-day change
- ▲ 3.4 pp
- Year-on-year
- ▲ 41.5 pp
- Primary use
- Multipurpose
- Operator
- BOR
- Coordinates
- 47.547°N, 112.429°W
- Last updated
- October 28, 2026
Recent readings
| Date | Fill level | Volume (hm³) |
|---|---|---|
| 28 Oct 2026 | 54.3% | 21.65 |
| 27 Oct 2026 | 53.9% | 21.47 |
| 26 Oct 2026 | 53.4% | 21.27 |
| 25 Oct 2026 | 53.0% | 21.11 |
| 24 Oct 2026 | 52.6% | 20.97 |
| 23 Oct 2026 | 52.2% | 20.78 |
| 22 Oct 2026 | 51.4% | 20.46 |
| 21 Oct 2026 | 50.9% | 20.28 |
| 20 Oct 2026 | 50.4% | 20.08 |
| 19 Oct 2026 | 49.9% | 19.89 |
| 18 Oct 2026 | 49.5% | 19.71 |
| 17 Oct 2026 | 49.0% | 19.53 |