Reservoir · Montana · United States · BOR RISE
Canyon Ferry Lake
Canyon Ferry Lake Dam Powerplant and Helena Valley Pumping Plant
79.1% full
Capacity
2,401.59 hm³
Volume stored
1899 hm³
Coordinates
46.649°N, 111.728°W
Last updated
2026-09-09
Current fill
79.1%vs 7 days ago
-1.0%losing
vs 1 year ago
+3.3%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: 2026-09-09.
Catchment Weather
Past 30 days + 14-day forecast · Open-Meteo
Satellite imagery: Esri, Maxar, Earthstar Geographics. Map: Esri, HERE, Garmin, © OpenStreetMap contributors. 46.649, -111.728 · Open in Google Maps
About Canyon Ferry Lake
As of September 9, 2026, Canyon Ferry Lake is filled to 79.1% of its total capacity, holding roughly 1,899 hm³ of water out of a maximum 2,402 hm³. At this level the reservoir is within its normal operating range.
Over the most recent week on record the fill level has held broadly steady (-1.0 pts), and it is 3.3 points above its level on the same date a year earlier.
Across the readings we hold for Canyon Ferry Lake — 1967 data points between September 12, 2021 and September 9, 2026 — the level has ranged from a low of 64.6% (February 26, 2022) to a high of 97.3% (July 8, 2022). On average the reservoir is fullest around July and at its lowest around March.
It is operated by BOR primarily for multiple purposes. It lies within the Montana basin at 46.649°N, 111.728°W.
Key facts
- Current fill level
- 79.1%
- Water stored
- 1,899 hm³
- Total capacity
- 2,402 hm³
- 7-day change
- ▼ 1.0 pts
- Year-on-year
- ▲ 3.3 pts
- Primary use
- Multipurpose
- River basin
- Montana
- Operator
- BOR
- Coordinates
- 46.649°N, 111.728°W
- Last updated
- September 9, 2026
Recent readings
| Date | Fill level | Volume (hm³) |
|---|---|---|
| 9 Sep 2026 | 79.1% | 1,899 |
| 8 Sep 2026 | 79.0% | 1,898 |
| 7 Sep 2026 | 79.2% | 1,902 |
| 6 Sep 2026 | 79.4% | 1,906 |
| 5 Sep 2026 | 79.6% | 1,911 |
| 4 Sep 2026 | 79.7% | 1,915 |
| 3 Sep 2026 | 80.0% | 1,920 |
| 2 Sep 2026 | 80.1% | 1,923 |
| 1 Sep 2026 | 80.2% | 1,925 |
| 31 Aug 2026 | 80.3% | 1,929 |
| 30 Aug 2026 | 80.5% | 1,932 |
| 29 Aug 2026 | 80.6% | 1,937 |