Rathbun Lake Water Level
Iowa · updated daily from the U.S. Geological Survey
905.73 ft
Rathbun Lake is above average for this time of year and steady (-0.13 ft in the last 7 days).
Change since yesterday: +0.03 ft
Reading as of 2026-08-14 · higher than 73% of August readings on record
Where Rathbun Lake sits historically
Today's level compared with every reading in our 5.0-year record for this lake.
Since yesterday
+0.03 ft
7-day change
-0.13 ft
30-day change
+0.11 ft
1-year change
-5.00 ft
Last 30 days
Last 12 months
Full history (5.0 years)
Rathbun Lake records and averages
| Current level | 905.73 ft |
|---|---|
| Record high | 910.99 ft (2026-06-15) |
| Record low | 902.37 ft (2023-12-21) |
| Average of all readings | 904.63 ft |
| Data span | 5.0 years (1,815 readings) |
Frequently asked questions
Is Rathbun Lake full right now?
As of 2026-08-14, Rathbun Lake sits at 905.73 ft, which is above average for this time of year.Over the past 30 days the level has risen 0.11 ft.
What is the water level at Rathbun Lake today?
The most recent reading is 905.73 ft (2026-08-14), sourced from the U.S. Geological Survey. Readings on this page refresh automatically as the agency publishes new data.
What is the highest Rathbun Lake has ever been?
The highest level in our records is 910.99 ft on 2026-06-15. The lowest is 902.37 ft on 2023-12-21. Our record covers about 5.0 years of readings.
Is Rathbun Lake low for this time of year?
Compared with every August in our records, the current level is higher than 73% of them — above average for this time of year. Seasonal comparison matters more than the raw number, because most reservoirs draw down predictably through late summer and refill over winter and spring.
Why is Rathbun 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. Rathbun Lake has risen 0.11 ft over the past 30 days. For the operational reason on any given week, check the U.S. Geological Survey directly.
How much has Rathbun Lake changed over the past year?
The level is -5.00 ft compared with this date last year (905.73 ft today). The full-history chart above covers 5.0 years, with a record high of 910.99 ft and a record low of 902.37 ft.
Nearby lakes in Iowa
Source: the U.S. Geological Survey. Readings are provisional and subject to revision by the publishing agency. All Iowa lake levels.