Lake St. Helen Water Level History
Thirty-day lake-level chart, recent highs and lows, net change and daily summaries from the matched USGS station.
Lake St. Helen water-level chart
Source: U.S. Geological Survey monitoring station ↗. Recent measurements may be provisional.
What has Lake St. Helen been doing?
Across the available 30-day series, Lake St. Helen is falling overall. The measured range runs from 1,154.77 ft to 1,155.06 ft, with a net change of -0.21 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 | 1154.84 ft | 1154.85 ft | 1154.86 ft |
| Oct 6 | 1154.85 ft | 1154.87 ft | 1154.89 ft |
| Oct 5 | 1154.88 ft | 1154.91 ft | 1154.93 ft |
| Oct 4 | 1154.91 ft | 1154.93 ft | 1154.96 ft |
| Oct 3 | 1154.92 ft | 1154.94 ft | 1154.95 ft |
| Oct 2 | 1154.95 ft | 1154.96 ft | 1154.99 ft |
| Oct 1 | 1154.88 ft | 1154.93 ft | 1154.97 ft |
| Sep 30 | 1154.87 ft | 1154.88 ft | 1154.89 ft |
| Sep 29 | 1154.86 ft | 1154.87 ft | 1154.88 ft |
| Sep 28 | 1154.87 ft | 1154.88 ft | 1154.89 ft |
| Sep 27 | 1154.87 ft | 1154.88 ft | 1154.89 ft |
| Sep 26 | 1154.88 ft | 1154.89 ft | 1154.90 ft |
| Sep 25 | 1154.88 ft | 1154.89 ft | 1154.90 ft |
| Sep 24 | 1154.87 ft | 1154.89 ft | 1154.90 ft |
| Sep 23 | 1154.86 ft | 1154.89 ft | 1154.90 ft |
| Sep 22 | 1154.86 ft | 1154.90 ft | 1154.91 ft |
| Sep 21 | 1154.88 ft | 1154.91 ft | 1154.92 ft |
| Sep 20 | 1154.91 ft | 1154.92 ft | 1154.93 ft |
| Sep 19 | 1154.91 ft | 1154.92 ft | 1154.93 ft |
| Sep 18 | 1154.91 ft | 1154.92 ft | 1154.92 ft |
| Sep 17 | 1154.90 ft | 1154.91 ft | 1154.92 ft |
| Sep 16 | 1154.88 ft | 1154.90 ft | 1154.91 ft |
| Sep 15 | 1154.77 ft | 1154.86 ft | 1154.90 ft |
| Sep 14 | 1154.77 ft | 1154.79 ft | 1154.82 ft |
| Sep 13 | 1154.81 ft | 1154.85 ft | 1154.88 ft |
| Sep 12 | 1154.86 ft | 1154.88 ft | 1154.89 ft |
| Sep 11 | 1154.89 ft | 1154.92 ft | 1154.94 ft |
| Sep 10 | 1154.94 ft | 1154.97 ft | 1154.99 ft |
| Sep 9 | 1154.98 ft | 1155.01 ft | 1155.02 ft |
| Sep 8 | 1155.00 ft | 1155.03 ft | 1155.05 ft |
Lake St. Helen level-history FAQ
How has Lake St. Helen water level changed over the last 30 days?
Across the available 30-day sensor series, the net change is -0.21 ft and the overall direction is falling.
What was the highest Lake St. Helen level in the last 30 days?
The highest reading in the available 30-day series is 1,155.06 ft.
What was the lowest Lake St. Helen level in the last 30 days?
The lowest reading in the available 30-day series is 1,154.77 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.