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This probabilistic forecast is issued by the North Central River Forecast Center.
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About this graph
Forecasts for the Mississippi River at Canton Lock and Dam 20 are issued routinely year-round.
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Upstream Gauge - at Gregory Landing Upstream Gauge Downstream Gauge Downstream Gauge - at LaGrange
Zoom Level:14
Flood Categories (in feet)
Major Flood Stage: 25
Moderate Flood Stage: 20
Flood Stage: 15
Action Stage: 13
Low Stage (in feet): -9999

Historic Crests
(1) 27.88 ft on 07/09/1993
(2) 27.73 ft on 06/18/2008
(3) 27.11 ft on 06/02/2019
(4) 24.50 ft on 04/24/1973
(5) 23.43 ft on 07/07/2014
(6) 23.20 ft on 05/15/2001
(7) 23.19 ft on 04/21/2013
(8) 21.42 ft on 05/01/1965
(9) 21.21 ft on 10/12/2018
(10) 20.92 ft on 10/04/1986
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(P): Preliminary values subject to further review.

Recent Crests
(1) 17.01 ft on 04/01/2020 (P)
(2) 17.57 ft on 10/17/2019
(3) 27.11 ft on 06/02/2019
(4) 21.21 ft on 10/12/2018
(5) 17.45 ft on 09/10/2018
(6) 16.68 ft on 07/03/2018
(7) 17.04 ft on 05/15/2018
(8) 16.74 ft on 06/03/2017
(9) 16.77 ft on 05/03/2017
(10) 14.99 ft on 04/07/2017
Show More Recent Crests

(P): Preliminary values subject to further review.

Low Water Records
(1) -4.00 ft on 12/26/1933
(2) -3.80 ft on 01/02/1934
(3) -3.60 ft on 12/14/1936
(4) -2.90 ft on 12/13/1937
(5) -2.80 ft on 01/17/1938
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Gauge LocationGauge Map Marker
Latitude/Longitude Disclaimer: The gauge location shown in the above map is the approximate location based on the latitude/longitude coordinates provided to the NWS by the gauge owner.
Flood Impacts & Photos Collapse
If you notice any errors in the below information, please contact our Webmaster
110000 At this approximate discharge, the Corps will raise the gates out of the water, creating "open river" conditions.
29.3 Water reaches the 12,000 volt transformer pad at Lock 20.
27 Water reaches the top of the lower gates.
26 The Lock and Dam 20 Control Center begins flooding at this height.
25.7 The Illinois levee protecting Meyer, IL is overtopped. The town of Meyer begins flooding.
24.5 Lock and Dam 20 maintenance buildings begin flooding.
21.7 Route B is closed from Poage Street in LaGrange to the south side of the LaGrange city limits near this height. This makes Route C the only way into and out of town.
20 Flood waters reach the top of the upper gates.
19.6 Water reaches the top of the lock wall, flooding the lock chamber.
19.5 In La Grange, Highway B begins to flood and is closed south of Route C.
19.3 Drainage District begins to fill up.
18.7 In La Grange, 2nd Street floods between Green St. and Lewis St.
18.6 In La Grange, Green Street floods.
18.2 In La Grange, MO, Bunge Car Park begins to flood.
18 Near this level, the lock is closed to navigation. This level will vary with circumstance. Also, Main Street leading to the lock and dam and the railroad crossing at Henderson Street flood at this height.
17.6 In La Grange, MO, the entrance to Mark Twain Casino parking lot begins to flood. Alternate entrance is used. Also, water reaches the base of area levees.
17.5 At this height, the city of Canton will install the flood gates at the railroad opening and at Route B north of town.
17.3 State Highway B, or Business U.S. Highway 61, is closed from Missouri Highway 16 in Canton to north of Canton at the levee flood gate near this level.
16.6 Front Street leading to the campground and Corps park campgrounds flood at this height.
16.4 Burlington Northern/Sante Fe railroad tracks are overtopped.
15.6 North Front Street and the first 2-3 campsites in Mississippi Park begin flooding at this height.
14 Both banks begin to overflow. Minor damages begin.
9 Above 8.7 to 9.2 feet, the Corps will raise the gates out of the water, allowing for "open river" conditions. This corresponds to a discharge of approximately 110,000 cfs.
8.5 The Corps will not allow the pool level to drop below 8.5 feet (higher flows below 100K). At low flows, they allow a 2-foot variation between 11.0 and 13.0 feet. At higher flows below 100K, the range is actually lower, between 8.5 and 10.5 feet. Above 110K cfs, the gates are raised above the water surface, allowing open river conditions.
(1) Canton riverfront with a stage of 23.05 on 19 June 2008.
(2) Canton riverfront on 19 June 2008 with a stage of 23.05 ft.
(3) Looking NE at the Canton Lock and Dam 20 on 19 June 2008. HT=23.05 feet.
(4) Flooded farm near Meyer, IL on 19 June 2008 with a stage of 23 feet.
(5) Levee break on the Illinois side across from Canton, MO on 19 June 2008. Stage was 23 feet.
(6) Knox Street in LaGrange with 2nd Street in the distance near flood at 18.2 feet on June 25, 2010.
(7) Flooded parking at Bunge near BNSF tracks in LaGrange on June 25, 2010 with a stage of 18.2 feet.
(8) Henderson Street leading to the lock and dam at the railroad crossing on June 25, 2010 at 18.15 feet
(9) East parking lot at Terrible's Casino in LaGrange on June 25, 2010 with a stage of 18.2 feet.
(10) West parking lot at Terrible's Casino in LaGrange at a stage of 18.2 feet on June 25, 2010
(11) BNSF railroad tracks looking north toward the lock and dam on June 25, 2010 at 18.15 feet.
(12) Mississippi RV Park outlets at Canton on June 25, 2010 at a stage of 18.15 feet.
(13) Front Street leading to campground hookups on June 25, 2010 at a stage of 18.15 feet.
(14) Aerial View
(15) Upstream View
(16) Downstream View
(17) Pool View (US from Dam)
(18) Tailwater Overview
(19) Tailwater View

Other Real-time and/or Archive Data Sources:

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The National Weather Service prepares its forecasts and other services in collaboration with agencies like the US Geological Survey, US Bureau of Reclamation, US Army Corps of Engineers, Natural Resource Conservation Service, National Park Service, ALERT Users Group, Bureau of Indian Affairs, and many state and local emergency managers across the country. For details, please click here.
NWS Information
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St. Charles, MO 63304
(636) 441-8467
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