Observed and urbanization-adjusted annual maximum peak discharge and associated urban fraction and precipitation values at USGS streamgage:
05532000 ADDISON CREEK AT BELLWOOD, IL
| Water year | Segment | Discharge code | Cumulative reservoir storage (acre-feet) | Urban fraction | Precipitation (inches) | Observed peak discharge (ft3/s) | Adjusted peak discharge (ft3/s) | Exceedance probability |
| 1951 | 1 | -- | 0 | 0.601 | 0.344 | 295 | 369 | 0.550 |
| 1952 | 1 | -- | 0 | 0.626 | 0.829 | 200 | 265 | 0.834 |
| 1953 | 1 | -- | 0 | 0.651 | 0.666 | 57 | 94 | 1.000 |
| 1954 | 1 | -- | 0 | 0.677 | 1.656 | 548 | 591 | 0.143 |
| 1955 | 1 | -- | 0 | 0.702 | 3.366 | 598 | 629 | 0.113 |
| 1956 | 1 | -- | 0 | 0.727 | 0.389 | 228 | 263 | 0.840 |
| 1957 | 1 | -- | 0 | 0.753 | 2.152 | 560 | 564 | 0.165 |
| 1958 | 1 | -- | 0 | 0.778 | 1.452 | 405 | 411 | 0.445 |
| 1959 | 1 | D | 0 | 0.803 | 0.670 | 273 | 280 | 0.800 |
| 1960 | 1 | -- | 0 | 0.828 | 0.770 | 295 | 291 | 0.771 |
| 1961 | 1 | -- | 0 | 0.835 | 1.762 | 588 | 550 | 0.179 |
| 1962 | 1 | -- | 0 | 0.841 | 1.729 | 260 | 256 | 0.856 |
| 1963 | 1 | -- | 0 | 0.847 | 1.384 | 325 | 311 | 0.721 |
| 1964 | 1 | -- | 0 | 0.854 | 0.909 | 284 | 273 | 0.817 |
| 1965 | 1 | -- | 0 | 0.860 | 0.386 | 434 | 403 | 0.466 |
| 1966 | 1 | -- | 0 | 0.867 | 1.678 | 499 | 457 | 0.321 |
| 1967 | 1 | -- | 0 | 0.873 | 1.025 | 264 | 249 | 0.874 |
| 1968 | 1 | -- | 0 | 0.879 | 1.723 | 584 | 524 | 0.203 |
| 1969 | 1 | -- | 0 | 0.886 | 0.839 | 553 | 494 | 0.244 |
| 1970 | 1 | D | 0 | 0.892 | 1.786 | 449 | 402 | 0.467 |
| 1971 | 1 | -- | 0 | 0.894 | 0.903 | 336 | 304 | 0.739 |
| 1972 | 1 | -- | 0 | 0.896 | 0.930 | 706 | 623 | 0.118 |
| 1973 | 1 | -- | 0 | 0.898 | 0.762 | 509 | 451 | 0.336 |
| 1974 | 1 | -- | 0 | 0.899 | 0.720 | 428 | 381 | 0.521 |
| 1975 | 1 | -- | 0 | 0.901 | 1.257 | 598 | 526 | 0.201 |
| 1976 | 1 | D | 0 | 0.903 | 0.963 | 454 | 402 | 0.469 |
| 1977 | 1 | E | 685 | 0.905 | 1.419 | 359 | 319 | 0.701 |
| 1978 | 1 | -- | 685 | 0.907 | 0.999 | 607 | 531 | 0.196 |
| 1979 | 1 | -- | 775 | 0.909 | 0.547 | 591 | 516 | 0.214 |
| 1980 | 1 | -- | 775 | 0.911 | 0.546 | 662 | 576 | 0.156 |
| 1981 | 1 | -- | 893 | 0.911 | 0.835 | 548 | 478 | 0.272 |
| 1982 | 1 | -- | 893 | 0.911 | 0.757 | 839 | 729 | 0.062 |
| 1983 | 1 | -- | 893 | 0.912 | 1.976 | 639 | 556 | 0.174 |
| 1984 | 1 | -- | 893 | 0.912 | 1.499 | 464 | 407 | 0.457 |
| 1985 | 1 | -- | 893 | 0.912 | 1.349 | 556 | 485 | 0.260 |
| 1986 | 1 | -- | 893 | 0.913 | 0.866 | 391 | 343 | 0.621 |
| 1987 | 1 | -- | 893 | 0.913 | 3.326 | 1120 | 968 | 0.022 |
| 1988 | 1 | -- | 893 | 0.913 | 0.590 | 370 | 325 | 0.680 |
| 1989 | 1 | -- | 893 | 0.913 | 2.019 | 541 | 471 | 0.285 |
| 1990 | 1 | -- | 893 | 0.914 | 3.292 | 895 | 775 | 0.048 |
| 1991 | 1 | -- | 893 | 0.914 | 2.870 | 675 | 586 | 0.148 |
| 1992 | 0 | C | 1308 | 0.914 | 1.586 | 351 | 336 | 0.644 |
| 1993 | 2 | C | 1308 | 0.914 | 1.824 | 517 | 536 | 0.192 |
| 1994 | 2 | C | 1308 | 0.915 | 2.006 | 425 | 442 | 0.363 |
| 1995 | 2 | CE | 1308 | 0.915 | 2.444 | 273 | 287 | 0.782 |
| 1996 | 2 | C | 1308 | 0.915 | 2.138 | 400 | 416 | 0.432 |
| 1997 | 2 | C | 1308 | 0.916 | 3.126 | 753 | 777 | 0.048 |
| 1998 | 2 | C | 1401 | 0.916 | 1.047 | 466 | 483 | 0.263 |
| 1999 | 2 | C | 1401 | 0.916 | 1.434 | 385 | 401 | 0.472 |
| 2000 | 2 | C | 1401 | 0.917 | 2.249 | 477 | 494 | 0.244 |
| 2001 | 2 | C | 1401 | 0.920 | 1.085 | 379 | 393 | 0.492 |
| 2002 | 2 | C | 1401 | 0.924 | 3.127 | 652 | 669 | 0.088 |
| 2003 | 2 | C | 1401 | 0.927 | 2.344 | 567 | 580 | 0.153 |
| 2004 | 2 | C | 1401 | 0.931 | 1.671 | 516 | 526 | 0.200 |
| 2005 | 2 | C | 1401 | 0.934 | 1.439 | 377 | 385 | 0.512 |
| 2006 | 2 | C | 1401 | 0.938 | 0.864 | 343 | 349 | 0.603 |
| 2007 | 2 | C | 1401 | 0.942 | 2.033 | 777 | 784 | 0.046 |
| 2008 | 2 | C | 1401 | 0.945 | 5.295 | 808 | 813 | 0.041 |
| 2009 | 2 | C | 1401 | 0.949 | 2.076 | 727 | 729 | 0.061 |