Highest listed crest 20.21 ft December 4, 1982; 44,800 cubic feet per second
Flood stage 13.0 ft Major flooding from 20.0 ft
Crests at major 1 101st of 177 gauges in Illinois
Most recent flood crest August 17, 2026 14.58 ft, moderate flooding Listed crests at the Mackinaw River near Congerville, 1945 to 2026 0 5 10 15 20 25 ft Flood stage 13.0 ft Major 20.0 ft Jun 16, 1945: 12.16 ft, action stage; 6,300 cubic feet per second Jun 20, 1946: 15.60 ft, moderate flooding; 14,300 cubic feet per second Apr 30, 1947: 16.02 ft, moderate flooding; 15,500 cubic feet per second Feb 28, 1948: 12.18 ft, action stage; 6,400 cubic feet per second Feb 13, 1949: 11.69 ft, action stage; 5,650 cubic feet per second Apr 26, 1950: 14.74 ft, moderate flooding; 11,800 cubic feet per second Jul 9, 1951: 19.41 ft, moderate flooding; 36,000 cubic feet per second Apr 13, 1952: 13.54 ft, minor flooding; 8,900 cubic feet per second Jul 6, 1953: 12.09 ft, action stage; 6,250 cubic feet per second May 29, 1954: 13.65 ft, minor flooding; 9,100 cubic feet per second Apr 20, 1955: 11.28 ft, action stage; 5,130 cubic feet per second May 29, 1956: 7.93 ft, below flood stage; 2,740 cubic feet per second Apr 29, 1957: 14.44 ft, moderate flooding; 11,100 cubic feet per second Jun 14, 1958: 12.37 ft, action stage; 6,700 cubic feet per second Feb 11, 1959: 15.29 ft, moderate flooding; 7,800 cubic feet per second Mar 30, 1960: 14.32 ft, moderate flooding; 10,000 cubic feet per second Sep 25, 1961: 14.87 ft, moderate flooding; 11,700 cubic feet per second Mar 12, 1962: 14.82 ft, moderate flooding; 11,400 cubic feet per second Mar 6, 1963: 10.50 ft, action stage; 4,230 cubic feet per second Apr 21, 1964: 11.60 ft, action stage; 5,320 cubic feet per second Apr 6, 1965: 14.95 ft, moderate flooding; 11,800 cubic feet per second Dec 25, 1965: 10.45 ft, action stage; 4,380 cubic feet per second Apr 2, 1967: 8.63 ft, below flood stage; 3,280 cubic feet per second Jun 26, 1968: 14.29 ft, moderate flooding; 10,000 cubic feet per second Jan 30, 1969: 9.73 ft, below flood stage; 3,940 cubic feet per second May 15, 1970: 14.33 ft, moderate flooding; 10,100 cubic feet per second Jul 14, 1971: 11.65 ft, action stage; 5,450 cubic feet per second Apr 22, 1972: 9.39 ft, below flood stage; 3,730 cubic feet per second Apr 23, 1973: 15.59 ft, moderate flooding; 13,800 cubic feet per second Jun 23, 1974: 17.48 ft, moderate flooding; 21,500 cubic feet per second Feb 24, 1975: 9.14 ft, below flood stage; 3,580 cubic feet per second Mar 5, 1976: 14.73 ft, moderate flooding; 8,030 cubic feet per second Aug 10, 1977: 13.89 ft, minor flooding; 6,990 cubic feet per second May 14, 1978: 10.66 ft, action stage; 4,360 cubic feet per second Mar 5, 1979: 18.35 ft, moderate flooding; 18,000 cubic feet per second Jun 3, 1980: 19.52 ft, moderate flooding; 31,900 cubic feet per second May 15, 1981: 15.31 ft, moderate flooding; 9,260 cubic feet per second Mar 12, 1982: 16.69 ft, moderate flooding; 12,600 cubic feet per second Dec 4, 1982: 20.21 ft, major flooding; 44,800 cubic feet per second Feb 13, 1984: 12.72 ft, action stage; 8,290 cubic feet per second Feb 24, 1985: 16.65 ft, moderate flooding; 13,900 cubic feet per second Nov 20, 1985: 17.62 ft, moderate flooding; 17,000 cubic feet per second Oct 4, 1986: 19.61 ft, moderate flooding; 35,300 cubic feet per second Apr 7, 1988: 6.77 ft, below flood stage; 2,380 cubic feet per second May 27, 1989: 4.99 ft, below flood stage; 1,310 cubic feet per second Mar 11, 1990: 18.06 ft, moderate flooding; 18,900 cubic feet per second Nov 28, 1990: 15.70 ft, moderate flooding; 11,600 cubic feet per second Jul 31, 1992: 8.11 ft, below flood stage; 3,380 cubic feet per second Jan 5, 1993: 17.38 ft, moderate flooding; 16,200 cubic feet per second Sep 15, 1993: 18.37 ft, moderate flooding; 15,800 cubic feet per second Oct 19, 1993: 13.66 ft, minor flooding; 8,970 cubic feet per second May 14, 1995: 17.33 ft, moderate flooding; 16,000 cubic feet per second May 28, 1996: 14.64 ft, moderate flooding; 9,980 cubic feet per second Feb 22, 1997: 13.60 ft, minor flooding; 8,550 cubic feet per second Feb 27, 1997: 12.82 ft, action stage; 7,560 cubic feet per second Mar 19, 1998: 14.04 ft, moderate flooding May 9, 1998: 16.42 ft, moderate flooding; 13,100 cubic feet per second May 18, 1999: 13.78 ft, minor flooding Jun 14, 1999: 16.89 ft, moderate flooding; 13,800 cubic feet per second May 28, 2000: 5.01 ft, below flood stage; 1,570 cubic feet per second Feb 10, 2001: 12.70 ft, action stage; 7,230 cubic feet per second May 12, 2002: 18.13 ft, moderate flooding; 19,400 cubic feet per second Jul 10, 2003: 13.48 ft, minor flooding; 8,040 cubic feet per second Jun 1, 2004: 11.17 ft, action stage; 5,760 cubic feet per second Jan 14, 2005: 18.45 ft, moderate flooding; 21,900 cubic feet per second Apr 18, 2006: 8.49 ft, below flood stage; 3,600 cubic feet per second Mar 24, 2007: 15.02 ft, moderate flooding; 10,400 cubic feet per second Jan 11, 2008: 18.22 ft, moderate flooding Feb 7, 2008: 17.04 ft, moderate flooding; 14,800 cubic feet per second Feb 18, 2008: 13.90 ft, minor flooding; 8,650 cubic feet per second Sep 15, 2008: 18.84 ft, moderate flooding; 25,400 cubic feet per second Dec 29, 2008: 14.37 ft, moderate flooding; 8,340 cubic feet per second Mar 11, 2009: 15.90 ft, moderate flooding; 10,600 cubic feet per second May 16, 2009: 12.78 ft, action stage; 6,730 cubic feet per second Nov 1, 2009: 17.44 ft, moderate flooding; 13,700 cubic feet per second Dec 26, 2009: 14.31 ft, moderate flooding; 8,280 cubic feet per second Apr 24, 2011: 11.51 ft, action stage; 6,090 cubic feet per second Dec 15, 2011: 6.00 ft, below flood stage; 2,300 cubic feet per second Apr 18, 2013: 18.79 ft, moderate flooding; 28,700 cubic feet per second Jun 2, 2013: 16.05 ft, moderate flooding; 11,700 cubic feet per second Feb 22, 2014: 14.53 ft, moderate flooding; 9,310 cubic feet per second Jul 11, 2015: 16.82 ft, moderate flooding; 15,300 cubic feet per second Dec 29, 2015: 19.09 ft, moderate flooding; 31,400 cubic feet per second May 1, 2017: 13.94 ft, minor flooding; 8,510 cubic feet per second Dec 3, 2018: 6.78 ft, below flood stage; 2,760 cubic feet per second Feb 5, 2019: 14.08 ft, moderate flooding Mar 10, 2019: 12.38 ft, action stage; 6,790 cubic feet per second May 2, 2019: 17.65 ft, moderate flooding; 18,800 cubic feet per second May 23, 2019: 10.35 ft, action stage; 5,050 cubic feet per second May 31, 2019: 11.93 ft, action stage; 6,240 cubic feet per second Sep 29, 2019: 10.87 ft, action stage; 5,550 cubic feet per second Jan 13, 2020: 11.51 ft, action stage; 6,090 cubic feet per second Apr 26, 2020: 14.45 ft, moderate flooding; 8,820 cubic feet per second Apr 30, 2020: 14.36 ft, moderate flooding; 8,690 cubic feet per second May 19, 2020: 16.92 ft, moderate flooding; 15,000 cubic feet per second Jul 16, 2020: 17.75 ft, moderate flooding; 20,300 cubic feet per second May 10, 2021: 9.99 ft, below flood stage; 4,410 cubic feet per second Jun 28, 2021: 13.03 ft, minor flooding; 6,910 cubic feet per second Oct 30, 2021: 10.30 ft, action stage; 4,930 cubic feet per second Feb 18, 2022: 11.09 ft, action stage Apr 1, 2022: 10.05 ft, action stage; 4,970 cubic feet per second Jan 27, 2024: 11.03 ft, action stage; 5,710 cubic feet per second Apr 29, 2024: 13.40 ft, minor flooding; 7,800 cubic feet per second Apr 4, 2026: 12.56 ft, action stage; 6,930 cubic feet per second Jun 13, 2026: 14.52 ft, moderate flooding; 9,300 cubic feet per second Jun 18, 2026: 13.10 ft, minor flooding; 7,420 cubic feet per second Aug 17, 2026: 14.58 ft, moderate flooding; 9,380 cubic feet per second Highest, 20.21 ft, Dec 4, 1982 1960 1980 2000 2020 Crests at or above flood stage, by decade Crests at or above flood stage per decade, Mackinaw River near Congerville 1940s: 2 1950s: 6 1960s: 5 1970s: 6 1980s: 7 1990s: 12 12 2000s: 12 2010s: 8 2020s: 9 1940s 1950s 1960s 1970s 1980s 1990s 2000s 2010s 2020s These are the crests the local National Weather Service office lists for the gauge: the highest on record and recent crests. Lesser floods between them may be missing, so counts by decade are a floor. Categories use today's flood stages. Levees, dams and channel changes since a crest can make old and new stages not directly comparable. Woodford County: every hazard · River floods across the country · Illinois
NOAA National Water Prediction Service, gauge CNGI2, retrieved October 30, 2026. Stages in feet on the gauge's own datum, not elevation. Crests are as the National Weather Service lists them; preliminary values may be revised.