Reservoirs

Near normal

Hungry Horse Reservoir water level

Live reservoir storage and water level in Flathead-Columbia basin, Montana

Data through Aug 26, 2026 · source last checked Aug 27, 2026 · page revised Aug 27, 2026

Cite
acre-feet
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Free to republish with attribution. The chart updates automatically as new data lands.
About this data
Source
US Bureau of Reclamation RISE; California reservoirs via CA DWR CDEC
Series
End-of-day reservoir storage
Geography
Hungry Horse Reservoir water level
Unit
acre-feet
Calculation
Daily reading
Last observation
Aug 26, 2026
Update frequency
Daily

Now 3.26M af, 1% below the 5-yr median, 94% of capacity.

Hungry Horse storage fell to 3.26M af, down 4.3% on the month. The reservoir is 1% below the 5-year median and at 94% of capacity.

The numbers
PeriodCurrentPriorChange
Week over week3.26M af3.29M af-1.0%
Month over month3.26M af3.40M af-4.3%
Year over year3.26M af3.30M af-1.5%
vs 5-yr median3.26M af3.30M af-1.5%
Reservoir facts
MeasureValueSource
Full pool elevation3,560 ft above sea levelUSBR
Maximum depth at the dam520 ftUSBR
Surface area at full pool24,100 acresUSACE NID
Total capacity3,467,179 acre-feetUSBR

Previous weeks

Week of Aug 19, 2026

Hungry Horse storage fell to 3.29M af, down 4.1% over the month. The reservoir is 1% below the 5-year median and stands at 95% of capacity.

An earlier week

Hungry Horse storage stands at 3.32M af, down 3.5% over the past month from 3.44M af. The reservoir sits 1% below its 5-year median for this date and holds 96% of capacity.

Week of Aug 13, 2026

Hungry Horse storage stood at 3.34M af, down 3.2% from the prior month and 1.0% week-over-week, with the reservoir at 96% of capacity. Storage is tracking the 5-year median.

About Hungry Horse Reservoir

Hungry Horse Dam holds back the South Fork of the Flathead River in northwest Montana, a Reclamation project wired into the Columbia River power system. The arch dam rises 564 feet, among the tallest in the country, behind a reservoir near 3.5 million acre-feet. Reclamation runs it mainly for hydropower and flood control, coordinated with the wider Columbia network.

Total capacity is 3.47M af, over the past five years storage has ranged from 2.39M af to 3.46M af.

Hungry Horse Reservoir is one of the 20 major reservoirs this site totals each day, and one of several it tracks in the Flathead-Columbia 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.