Mississippi River at Grafton

1. 37.00 ftNear this height, floodwater begins to impact Grafton City Hall.
2. 33.50 ftNutwood Levee is Overtopped.
3. 32.10 ftMethodist Church at Main St. and Vine St. begins flooding.
4. 31.00 ftThe hangars at the south end of Smartt field begin to flood.
5. 30.90 ftMissouri Route B from Washeon Road to Seeburger Road is closed near this height.
6. 30.10 ftWater reaches the intersection of Main Street and Maple Street.
7. 29.10 ftWater reaches Main at Church Street.
8. 29.00 ftRoute 100 between Grafton and Alton at Clifton Terrace is flooded near this height.
9. 28.80 ftWater begins entering the north hangars at Smartt Field.
10. 28.50 ftWater begins entering the ramps on the north end of Smartt Field as the northwest and northeast corners are already flooded.
11. 28.40 ftWater reaches Main Street at the Vistors Center
12. 28.30 ftIntersection at Main (Route 100) & Route 3 is closed. Also at this level the Northeast Corner of Smartt Airfield begins flooding. Grafton Hills Drive is closed to all but local and select (UPS, FedEx, and Amazon) delivery traffic.
13. 28.00 ftAgricultural levee north of Highway 370 is overtopped, flooding a St. Peters recreational area around a lake near 370 and Truman.
14. 27.60 ftBeasley Fish Market at Main Street and Overmeyer begins flooding.
15. 27.50 ftThe intersection at Main Street and Dagget Hollow begins flooding.
16. 26.50 ftAt this height the entrance to the Illinois Youth Center-Pere Marquette becomes flooded, forcing the evacuation of those staying there.
17. 26.40 ftResidential flooding in Grafton occurs.
18. 26.00 ftWater distribution system begins to flood so emergency measures begin.
19. 25.60 ftWater surrounds base of Aerie's Resort at Main Street (Hwy 100) near Market.
20. 25.50 ftBrussels Ferry closes near this height. O'Jan's Fish Stand in Grafton closes near this height.
21. 25.20 ftThe intersection at Main Street and Canal Street begins flooding.
22. 25.00 ftBall field south of Main Street and Hawg Pit BBQ begin flooding.
23. 24.90 ftWater reaches the intersection of Main St. and Edwards St.
24. 24.70 ftCity of Grafton begins to detour traffic along Route 100 (Main Street) at Evans Street. Also at this level the Catholic Church parking lot at Main & Evans begins flooding. This represents the lowest point on Main Street in Grafton.
25. 24.00 ftRoads within Chautauqua and Elsah begin flooding near this height.

Chance of flooding, September to November

The three-month chances are the River Forecast Centers’ long-range flood outlook, issued August 28, 2026.

Most recent crests

• May 16, 2024: 20.13 ft
• May 2, 2024: 20.71 ft
• May 10, 2023: 20.80 ft
• May 7, 2022: 21.28 ft
• April 14, 2021: 20.66 ft
• March 20, 2021: 21.86 ft
• July 3, 2020: 19.48 ft
• June 1, 2020: 22.54 ft
• March 31, 2020: 22.38 ft
• January 13, 2020: 20.12 ft

• UpstreamMississippi River at Winfield Lock and Dam 25
• DownstreamMississippi River at Alton
• Missouri River at St. Charles
• Dardenne Creek at St. Peters
• Illinois River at Hardin
• Mississippi River at Mel Price (Alton) Lock and Dam
• Cuivre River at Old Monroe
• Dardenne Creek at O'Fallon

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>

Stage, flood stages, impacts and crest history from NOAA’s National Water Prediction Service. Streamflow and the daily record from the U.S. Geological Survey.