How Full Is Lake Powell?

How many acre-feet does Lake Powell hold?

The figure above comes from official daily reservoir storage records, which report stored water in acre-feet. One acre-foot is the volume of water covering one acre to a depth of one foot. This is not a water-height measurement.

Why “percent full” needs a capacity definition

USBR’s 2026 reservoir map uses a reference maximum of 24,322,000 acre-feet. We divide the reported storage by that stated reference to produce the percentage above. This calculation is distinct from Reclamation’s published percentage of live capacity, and capacity estimates can be updated as sedimentation and surveys change.

Is Lake Powell gaining or losing water?

The 7-day and year-over-year comparisons above use storage observations on matching calendar dates. Positive changes indicate more stored water and negative changes indicate less; observed storage may vary with releases, runoff and reservoir operations. Stored water and water level are both reported daily; their latest observation dates may still differ.

What is the difference between storage and elevation?

Elevation is measured in feet above a specified vertical datum. Storage is the estimated volume contained in the reservoir, measured in acre-feet. Compare these with care. For a longer record of water-surface elevation, open our 1963-to-today historical level table.