Reservoirs

Near normal

Canyon Ferry Lake level

Live reservoir storage and water level in Missouri basin, Montana

Data through Oct 15, 2026 · source last checked Oct 17, 2026 · page revised Oct 16, 2026

Cite
acre-feet
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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
Oct 15, 2026
Update frequency
Daily

Now 1.48M af, 1% above the 5-yr median, 78% of capacity.

Canyon Ferry storage fell 2.4% over the month to 1.48M af, 78% of capacity. It sits 1% above the 5-year median and 4.6% higher than a year ago.

The numbers
PeriodCurrentPriorChange
Week over week1.48M af1.48M af+0.1%
Month over month1.48M af1.52M af-2.4%
Year over year1.48M af1.42M af+4.6%
vs 5-yr median1.48M af1.46M af+1.5%
Water surface elevation
MeasureValue
Latest reading, Oct 15, 20263,784.54 ft above sea level
Change from a week earlier+0.04 ft
Change from a year earlier+2.17 ft
5-yr median for the date3,783.84 ft
Above the top of active conservation pool14.54 ft
Five-year low3,776.77 ft (Feb 27, 2022)
Five-year high3,797.21 ft (Jul 1, 2023)
Reservoir facts
MeasureValueSource
Full pool elevation3,770 ft above sea level (top of active conservation pool)USBR
Maximum depth at the dam172 ftUSBR
Surface area at full pool34,435 acresUSACE NID
Total capacity1,886,950 acre-feetUSBR

Previous weeks

An earlier week

Canyon Ferry Lake held 1.48M af, essentially flat week over week and 1% above the 5-year median. Storage fell 2.7% on the month from 1.52M af, but was up 4.6% year over year.

Week of Oct 7, 2026

Canyon Ferry Lake storage fell to 1.49M af, down 3.7% from a month earlier. Storage sits 1% above its 5-year median, holding 79% of capacity. Year-over-year, the lake is up 5.1%.

Week of Sep 23, 2026

Canyon Ferry Lake storage stands at 1.51M af, down 5.0% over the month. The lake is at 80% of capacity and holding at the 5-year median. Year over year, storage is up 4.8%.

Week of Sep 15, 2026

Canyon Ferry storage stands at 1.52M af, down 5.7% from a month ago but up 4.4% year over year. At 81% of capacity, the reservoir sits at the 5-year median.

About Canyon Ferry Lake

Canyon Ferry Lake's water level is 3,784.54 feet above sea level as of Oct 15, 2026, 14.54 feet above the top of active conservation pool (3,770 feet), with 1.48 million acre-feet in storage (78% of capacity). That is 0.04 feet higher than a week earlier and 2.17 feet higher than a year earlier.

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 21 major reservoirs this site totals each day. For the combined picture, western reservoir levels carries the storage of all 21 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 and the elevation table tracks the water surface in feet, so read storage against total capacity for how full the reservoir is, and the elevation 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.