Reservoirs
Near normalCanyon Ferry Lake level
Live reservoir storage and water level in Missouri basin, Montana
Data through Aug 26, 2026 · source last checked Aug 27, 2026 · page revised Aug 27, 2026
Cite
- Storage
About this data
- Source
- US Bureau of Reclamation RISE; California reservoirs via CA DWR CDEC
- Series
- End-of-day reservoir storage
- Geography
- Canyon Ferry Lake level
- Unit
- acre-feet
- Calculation
- Daily reading
- Last observation
- Aug 26, 2026
- Update frequency
- Daily
Now 1.58M af, 2% below the 5-yr median, 84% of capacity.
Canyon Ferry storage is 1.58M af, down 5.5% over the past month. The lake is 2% below the 5-year median at 84% of capacity, up 3.7% year over year.
| Period | Current | Prior | Change |
|---|---|---|---|
| Week over week | 1.58M af | 1.60M af | -1.4% |
| Month over month | 1.58M af | 1.67M af | -5.5% |
| Year over year | 1.58M af | 1.52M af | +3.7% |
| vs 5-yr median | 1.58M af | 1.61M af | -1.8% |
| Measure | Value | Source |
|---|---|---|
| Full pool elevation | 3,770 ft above sea level (top of active conservation pool) | USBR |
| Maximum depth at the dam | 172 ft | USBR |
| Surface area at full pool | 34,435 acres | USACE NID |
| Total capacity | 1,886,950 acre-feet | USBR |
Previous weeks
Week of Aug 19, 2026
Canyon Ferry storage fell to 1.60M af, down 1.2% on the week. Month-over-month storage declined 4.9%, leaving the lake 2% below the 5-year median. Year-over-year, the lake is up 2.9%.
An earlier week
Canyon Ferry Lake storage fell to 1.62M af, down 4.3% over the month. The lake sits 3% below its 5-year median and holds 86% of capacity. Year over year, storage is up 1.9%.
Week of Aug 13, 2026
Canyon Ferry storage fell to 1.63M af on August 9, down 3.7% from a month earlier and 4% below the 5-year median. The reservoir sits at 86% of capacity. Storage is up 2.0% from a year ago.
About Canyon Ferry Lake
Canyon Ferry Dam impounds the Missouri River east of Helena, part of the Pick-Sloan Missouri Basin Program. Reclamation operates it for hydropower, irrigation, flood control, and recreation. Covering better than 33,000 acres, it is Montana's third-largest body of water and a heavily used recreation lake in the state's western valleys.
Total capacity is 1.89M af, over the past five years storage has ranged from 1.26M af to 1.89M af.
Canyon Ferry Lake is one of the 20 major reservoirs this site totals each day, and one of several it tracks in the Missouri basin. For the combined picture, western reservoir levels carries the storage of all 20 on one chart, which is the number to watch when the question is about the West as a whole rather than about this project.
Those figures describe the reservoir at full pool, not today. The chart at the top of this page tracks storage in acre-feet rather than water depth, so read the current figure against total capacity for how full the reservoir is, and against the full pool elevation and maximum depth for the size of the water column behind the dam. The two do not move together one for one: a reservoir narrows as it deepens, so one holding half its capacity still stands more than half as deep.
Sources: full pool elevation and maximum depth from the Bureau of Reclamation; surface area from the Army Corps' National Inventory of Dams; total capacity from the Bureau of Reclamation.