Mississippi River at Quincy Lock and Dam 21
Observed Tue, Sep 22, 11:30 PM CDT
- Flood stage
- 18.00 ft
- Forecast crest
- 16.50 ftFri, Sep 25, 7:00 AM CDT
- Record crest
- 31.30 ft1993
Flood stages and impacts
| Category | Stage |
|---|---|
| Major flood | 25.00 ft |
| Moderate flood | 21.00 ft |
| Minor flood | 18.00 ft |
| Action | 16.00 ft |
- 140000.0 ftAt this approximate discharge, the Corps will raise the gates out of the water, creating "open river" conditions.
- 26.90 ftMissouri Highway 168 east of Palmyra near the BASF plant closes near this height.
- 25.70 ftAt this height, the lock wall is inundated.
- 25.00 ftQuincy Waterworks inundated.
- 21.90 ftNear this level, the lock is closed to navigation. This level will vary with circumstance.
- 14.00 ftUnprotected bottomlands flood.
- 12.30 ftThis is the upper limit of the target pool level at Lock and Dam 21.
- 12.20 ftThis is the target pool level for navigation at Lock & Dam 21.
- 12.00 ftAt some point between 11.6 to 12.1 feet, the Corps will lift all gates out of the river creating "open river" conditions, corresponding to an approximate discharge of 140,000 cfs.
- 11.80 ftThis is the lower limit of the target pool level at Lock & Dam 21.
Flood outlook
Chance of flooding, September to November
| Category | Chance |
|---|---|
| Minor flooding | 10% |
| Moderate flooding | Under 5% |
| Major flooding | Under 5% |
The three-month chances are the River Forecast Centers’ long-range flood outlook, issued August 28, 2026.
Crest history
55 crests on NOAA’s list since 1947.
| # | Date | Stage |
|---|---|---|
| 1 | July 13, 1993 | 31.30 ft |
| 2 | June 1, 2019 | 30.15 ft |
| 3 | June 18, 2008 | 29.58 ft |
| 4 | April 25, 1973 | 27.70 ft |
| 5 | April 21, 2013 | 27.24 ft |
| 6 | May 16, 2001 | 26.55 ft |
| 7 | July 8, 2014 | 26.15 ft |
| 8 | October 4, 1986 | 24.86 ft |
| 9 | June 1, 2013 | 24.74 ft |
| 10 | May 29, 1996 | 24.05 ft |
| 11 | October 12, 2018 | 23.96 ft |
| 12 | April 28, 1965 | 23.89 ft |
| 13 | April 5, 1983 | 23.51 ft |
| 14 | April 4, 1960 | 23.45 ft |
| 15 | June 10, 1947 | 23.32 ft |
| 16 | June 16, 2011 | 22.80 ft |
| 17 | April 15, 1998 | 22.73 ft |
| 18 | April 28, 2001 | 22.60 ft |
| 19 | May 5, 2008 | 22.45 ft |
| 20 | April 24, 2011 | 22.21 ft |
| 21 | June 24, 2010 | 21.60 ft |
| 22 | March 12, 2009 | 21.16 ft |
| 23 | December 29, 2015 | 21.08 ft |
| 24 | May 13, 2002 | 20.89 ft |
| 25 | July 21, 2010 | 20.86 ft |
Most recent crests
- April 28, 2026: 18.56 ft
- May 5, 2023: 20.37 ft
- April 2, 2020: 18.86 ft
- October 17, 2019: 19.16 ft
- October 2, 2019: 17.29 ft
- June 1, 2019: 30.15 ft
- October 12, 2018: 23.96 ft
- September 9, 2018: 19.62 ft
- July 5, 2018: 18.47 ft
- May 16, 2018: 18.90 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 year-round. 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. For the latest navigation status update from the U.S. Army Corps of Engineers-St. Louis District, <a href="http://www.mvs.usace.army.mil/Missions/Navigation/Status-Reports/">click here.</a>
Sources
Stage, flood stages, impacts and crest history from NOAA’s National Water Prediction Service.