Castle Lake Water Level
Washington · updated daily from the U.S. Geological Survey
2577.62 ft
Castle Lake is current reading available and steady (+0.00 ft in the last 7 days).
Change since yesterday: +0.02 ft
Reading as of 2026-08-15
Where Castle Lake sits historically
Today's level compared with every reading in our 0.1-year record for this lake.
Since yesterday
+0.02 ft
7-day change
+0.00 ft
30-day change
-0.15 ft
1-year change
— ft
Last 30 days
Last 12 months
Castle Lake records and averages
| Current level | 2577.62 ft |
|---|---|
| Record high | 2577.95 ft (2026-06-28) |
| Record low | 2577.59 ft (2026-08-11) |
| Average of all readings | 2577.75 ft |
| Data span | 0.1 years (53 readings) |
Frequently asked questions
Is Castle Lake full right now?
As of 2026-08-15, Castle Lake sits at 2577.62 ft, which is current reading available.Over the past 30 days the level has fallen 0.15 ft.
What is the water level at Castle Lake today?
The most recent reading is 2577.62 ft (2026-08-15), sourced from the U.S. Geological Survey. Readings on this page refresh automatically as the agency publishes new data.
What is the highest Castle Lake has ever been?
The highest level in our records is 2577.95 ft on 2026-06-28. The lowest is 2577.59 ft on 2026-08-11. Our record covers about 0.1 years of readings.
Why is Castle Lake changing right now?
Reservoir levels move for four main reasons: rainfall and runoff into the basin, releases through the dam for downstream water supply, power generation or flood control, evaporation during hot months, and seasonal drawdown schedules set by the operating agency. Castle Lake has fallen 0.15 ft over the past 30 days. For the operational reason on any given week, check the U.S. Geological Survey directly.
How much has Castle Lake changed over the past year?
Year-over-year comparison is not available for this lake yet. The full-history chart above covers 0.1 years, with a record high of 2577.95 ft and a record low of 2577.59 ft.
Nearby lakes in Washington
Source: the U.S. Geological Survey. Readings are provisional and subject to revision by the publishing agency. All Washington lake levels.