Lake Mendota Water Level History
Thirty-day lake-level chart, recent highs and lows, net change and daily summaries from the matched USGS station.
Lake Mendota water-level chart
Source: U.S. Geological Survey monitoring station ↗. Recent measurements may be provisional.
What has Lake Mendota been doing?
Across the available 30-day series, Lake Mendota is rising overall. The measured range runs from 849.6 ft to 850.25 ft, with a net change of +0.24 ft.
Lake levels can respond to rainfall, watershed inflow, dam and hydropower operations, seasonal target elevations, evaporation and downstream release requirements. This page reports what the matched sensor measured; it does not infer why an operator changed a reservoir.
Recent daily levels
| Date | Low | Average | High |
|---|---|---|---|
| Oct 7 | 850.12 ft | 850.13 ft | 850.14 ft |
| Oct 6 | 850.12 ft | 850.14 ft | 850.16 ft |
| Oct 5 | 850.13 ft | 850.15 ft | 850.17 ft |
| Oct 4 | 850.14 ft | 850.17 ft | 850.22 ft |
| Oct 3 | 850.13 ft | 850.17 ft | 850.25 ft |
| Oct 2 | 850.15 ft | 850.17 ft | 850.20 ft |
| Oct 1 | 849.83 ft | 850.12 ft | 850.21 ft |
| Sep 30 | 849.97 ft | 850.01 ft | 850.06 ft |
| Sep 29 | 849.99 ft | 850.01 ft | 850.03 ft |
| Sep 28 | 850.01 ft | 850.02 ft | 850.03 ft |
| Sep 27 | 849.93 ft | 850.03 ft | 850.06 ft |
| Sep 26 | 850.00 ft | 850.03 ft | 850.05 ft |
| Sep 25 | 850.03 ft | 850.04 ft | 850.07 ft |
| Sep 24 | 850.03 ft | 850.04 ft | 850.06 ft |
| Sep 23 | 850.04 ft | 850.05 ft | 850.06 ft |
| Sep 22 | 850.05 ft | 850.05 ft | 850.06 ft |
| Sep 21 | 850.01 ft | 850.05 ft | 850.09 ft |
| Sep 20 | 849.98 ft | 850.03 ft | 850.06 ft |
| Sep 19 | 849.72 ft | 849.91 ft | 850.05 ft |
| Sep 18 | 849.69 ft | 849.77 ft | 849.81 ft |
| Sep 17 | 849.74 ft | 849.78 ft | 849.80 ft |
| Sep 16 | 849.76 ft | 849.79 ft | 849.81 ft |
| Sep 15 | 849.60 ft | 849.80 ft | 849.96 ft |
| Sep 14 | 849.72 ft | 849.76 ft | 849.79 ft |
| Sep 13 | 849.78 ft | 849.80 ft | 849.83 ft |
| Sep 12 | 849.75 ft | 849.82 ft | 849.86 ft |
| Sep 11 | 849.81 ft | 849.83 ft | 849.84 ft |
| Sep 10 | 849.84 ft | 849.85 ft | 849.86 ft |
| Sep 9 | 849.81 ft | 849.86 ft | 849.87 ft |
| Sep 8 | 849.82 ft | 849.86 ft | 849.88 ft |
Lake Mendota level-history FAQ
How has Lake Mendota water level changed over the last 30 days?
Across the available 30-day sensor series, the net change is +0.24 ft and the overall direction is rising.
What was the highest Lake Mendota level in the last 30 days?
The highest reading in the available 30-day series is 850.25 ft.
What was the lowest Lake Mendota level in the last 30 days?
The lowest reading in the available 30-day series is 849.6 ft.
Are historical USGS lake readings final?
Not always. Recent readings may be marked provisional and can be revised by the source agency after quality review.