Reservoir · Montana · United States · BOR RISE
Bighorn River and BIA Canal near St. Xavier
80.6% full
Capacity
3.55 hm³
Volume stored
3 hm³
Coordinates
45.317°N, 107.918°W
Last updated
2026-09-09
Current fill
80.6%vs 7 days ago
+6.8%gaining
vs 1 year ago
+5.4%year-over-year
7-day trend
↑rising
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: 2026-09-09.
Catchment Weather
Past 30 days + 14-day forecast · Open-Meteo
Satellite imagery: Esri, Maxar, Earthstar Geographics. Map: Esri, HERE, Garmin, © OpenStreetMap contributors. 45.317, -107.918 · Open in Google Maps
About Bighorn River and BIA Canal near St. Xavier
As of September 9, 2026, Bighorn River and BIA Canal near St. Xavier is filled to 80.6% of its total capacity, holding roughly 3 hm³ of water out of a maximum 4 hm³. At this level the reservoir is high.
Over the most recent week on record the fill level has risen by 6.8 percentage points, and it is 5.4 points above its level on the same date a year earlier.
Across the readings we hold for Bighorn River and BIA Canal near St. Xavier — 1951 data points between September 12, 2021 and September 9, 2026 — the level has ranged from a low of 18.0% (September 13, 2023) to a high of 99.7% (August 7, 2026). On average the reservoir is fullest around July and at its lowest around October.
It is operated by BOR primarily for multiple purposes. It lies within the Montana basin at 45.317°N, 107.918°W.
Key facts
- Current fill level
- 80.6%
- Water stored
- 3 hm³
- Total capacity
- 4 hm³
- 7-day change
- ▲ 6.8 pts
- Year-on-year
- ▲ 5.4 pts
- Primary use
- Multipurpose
- River basin
- Montana
- Operator
- BOR
- Coordinates
- 45.317°N, 107.918°W
- Last updated
- September 9, 2026
Recent readings
| Date | Fill level | Volume (hm³) |
|---|---|---|
| 9 Sep 2026 | 80.6% | 3 |
| 8 Sep 2026 | 69.6% | 2 |
| 7 Sep 2026 | 69.6% | 2 |
| 6 Sep 2026 | 73.2% | 3 |
| 5 Sep 2026 | 75.5% | 3 |
| 4 Sep 2026 | 75.8% | 3 |
| 3 Sep 2026 | 75.5% | 3 |
| 2 Sep 2026 | 73.8% | 3 |
| 1 Sep 2026 | 73.0% | 3 |
| 31 Aug 2026 | 79.4% | 3 |
| 30 Aug 2026 | 83.4% | 3 |
| 29 Aug 2026 | 82.3% | 3 |