Mississippi River below Lock and Dam 4 - Alma
Observed Wed, Sep 30, 2:15 PM CDT
- Flood stage
- 16.00 ft
- Forecast crest
- 4.50 ftWed, Sep 30, 7:00 PM CDT
- Record crest
- 19.78 ft1965
Flood stages and impacts
| Category | Stage |
|---|---|
| Major flood | 18.00 ft |
| Moderate flood | 17.00 ft |
| Minor flood | 16.00 ft |
| Action | 10.00 ft |
- 20.00 ftWater reaches the top of the protective earthen dike.
- 19.80 ftThe water reaches the flood of record set in 1965.
- 16.50 ftAgriculture and recreational land is flooded.
- 16.00 ftLock gates and walls at Dam 4 go underwater.
- 15.50 ftLock and Dam 4 is closed to navigation.
Flood outlook
Chance of flooding, October to December
| Category | Chance |
|---|---|
| Minor flooding | Under 5% |
| Moderate flooding | Under 5% |
| Major flooding | Under 5% |
The three-month chances are the River Forecast Centers’ long-range flood outlook, issued September 25, 2026.
Crest history
11 crests on NOAA’s list since 1951.
| # | Date | Stage |
|---|---|---|
| 1 | April 19, 1965 | 19.78 ft |
| 2 | April 16, 2001 | 18.15 ft |
| 3 | April 18, 1969 | 17.53 ft |
| 4 | April 25, 2023 | 17.05 ft |
| 5 | April 18, 1952 | 16.30 ft |
| 6 | April 16, 1951 | 16.20 ft |
| 7 | April 11, 1997 | 15.60 ft |
| 8 | April 5, 1967 | 15.35 ft |
| 9 | June 25, 1993 | 14.93 ft |
| 10 | April 14, 2011 | 14.75 ft |
| 11 | September 29, 2010 | 12.34 ft |
Most recent crests
- April 25, 2023: 17.05 ft
- April 14, 2011: 14.75 ft
- September 29, 2010: 12.34 ft
- April 16, 2001: 18.15 ft
- April 11, 1997: 15.60 ft
- June 25, 1993: 14.93 ft
- April 18, 1969: 17.53 ft
- April 5, 1967: 15.35 ft
- April 19, 1965: 19.78 ft
- April 18, 1952: 16.30 ft
Nearby
Upstream, downstream and the gauges around this one.
What this means
Forecasts by the North Central River Forecast Center. Forecasts are issued routinely during the navigation season, and as needed at other times of the year. River forecasts for this location take into account past precipitation and the precipitation amounts expected approximately 24 hours into the future from the forecast issuance time. River forecasts for this location take into account past precipitation and the precipitation amounts expected approximately 48 hours into the future from the forecast issuance time.
Sources
Stage, flood stages, impacts and crest history from NOAA’s National Water Prediction Service.