About Our Water Level Data

Where does our water level come from?

Our latest water level and historical charts use the Bureau of Reclamation’s official Lake Powell daily elevation records. Each observation has a calendar date, which may differ from the day you visit. Published values can be revised.

What do the charts show?

All water-level charts use the same daily observations. You can view recent readings for a week, month or year, compare monthly averages across years or explore annual highs and lows dating back to 1963. Missing days are not estimated.

You can explore the original historical water-level records. Annual figures cover the available dates for each year; the current year is not yet complete.

What does “how full” mean?

Water level is the height of the lake surface in feet. Water storage is the amount of water held in the reservoir, measured in acre-feet. They describe different things, so a change in lake height does not translate directly into the same percentage change in stored water.

Our storage figures come from official reservoir storage records. The percentage shown on the site compares stored water with the published 2026 reference capacity of 24.322 million acre-feet. It is not the official live-capacity percentage.

Why do we use NGVD29?

All water heights here use NGVD29, the traditional Lake Powell elevation reference. This keeps today's water level consistent with familiar milestones such as full pool at 3,700 ft, minimum power pool at 3,490 ft and dead pool at 3,370 ft.

How current is the information?

Water level and storage are reported as daily reservoir records, but they may not be published at exactly the same time. Long-term annual summaries are refreshed periodically. Always check each figure’s observation date, especially before making comparisons.

If official data are temporarily unavailable, we indicate that rather than guessing a new value. These readings can be revised. For boating, reservoir operations or safety decisions, consult the original agency information directly.