Mississippi River Pool Lock and Dam 26 at Alton, IL
Is Mississippi River Pool Lock and Dam 26 at Alton, IL flooding right now?
Mississippi River Pool Lock and Dam 26 at Alton, IL measured 16.24 ft on 2026-09-22 21:30:00 UTC. That observation was 4.8 ft below its 21 ft flood stage. This is the latest available reading, not a guarantee of current conditions.
Gauge height
16.24 ft
Streamflow
—
Minor flooding here begins at 21 ft, with major flooding at 31 ft. The highest crest on record was 39.55 ft on Sun, Aug 1, 1993.
Flood stages at this gauge
| Category | Stage | Current distance |
|---|---|---|
| Action | 20 ft | 3.8 ft below |
| Minor flood | 21 ft | 4.8 ft below |
| Moderate flood | 24 ft | 7.8 ft below |
| Major flood | 31 ft | 14.8 ft below |
Highest crests on record
| Stage | Date |
|---|---|
| 39.55 ft | 1993-08-01 |
| 35.3 ft | 2019-06-09 |
| 31.94 ft | 2016-01-01 |
| 31.6 ft | 2019-05-07 |
| 31.43 ft | 1995-05-22 |
Nearby gauges
| Gauge | Distance | County |
|---|---|---|
| Coldwater Creek near Black Jack, MO | 6.0 mi | St. Louis County |
| Mill Creek near Florissant, MO | 6.1 mi | St. Louis County |
| Spanish Lake Tributary. near Black Jack, MO | 6.4 mi | St. Louis County |
| Piasa Creek near Melville, IL | 6.8 mi | Madison County |
| Watkins Creek near Bellefontaine Neighbors, MO | 7.9 mi | St. Louis County |
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Provisional data: Real-time readings are provisional and subject to revision by the USGS — sensors can be affected by ice, debris, or equipment malfunction. Do not rely on this site for decisions involving personal safety; follow official guidance from the National Weather Service and local authorities.