Observed and urbanization-adjusted annual maximum peak discharge and associated urban fraction and precipitation values at USGS streamgage:
05530000 WELLER CREEK AT DES PLAINES, 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 | 0.647 | 0.588 | 245 | 409 | 0.899 |
| 1952 | 1 | -- | 0 | 0.676 | 1.530 | 328 | 489 | 0.785 |
| 1953 | 1 | E | 0 | 0.706 | 1.505 | 169 | 287 | 0.973 |
| 1954 | 1 | -- | 0 | 0.735 | 3.112 | 461 | 608 | 0.582 |
| 1955 | 1 | -- | 0 | 0.764 | 4.741 | 535 | 676 | 0.479 |
| 1956 | 1 | -- | 0 | 0.794 | 1.562 | 245 | 340 | 0.952 |
| 1957 | 1 | -- | 0 | 0.823 | 5.799 | 668 | 779 | 0.315 |
| 1958 | 1 | -- | 0 | 0.853 | 1.594 | 384 | 456 | 0.832 |
| 1959 | 1 | E | 0 | 0.882 | 1.867 | 376 | 431 | 0.868 |
| 1960 | 1 | -- | 0 | 0.911 | 1.890 | 562 | 605 | 0.586 |
| 1961 | 1 | -- | 0 | 0.917 | 2.813 | 596 | 637 | 0.538 |
| 1962 | 1 | -- | 0 | 0.922 | 2.645 | 394 | 426 | 0.876 |
| 1963 | 1 | D | 0 | 0.927 | 1.554 | 478 | 509 | 0.754 |
| 1964 | 1 | -- | 0 | 0.933 | 0.455 | 432 | 458 | 0.828 |
| 1965 | 1 | -- | 0 | 0.938 | 0.236 | 336 | 358 | 0.942 |
| 1966 | 1 | D | 0 | 0.943 | 1.150 | 1530 | 1570 | 0.026 |
| 1967 | 1 | -- | 0 | 0.949 | 1.544 | 1590 | 1620 | 0.023 |
| 1968 | 1 | -- | 0 | 0.954 | 1.303 | 1140 | 1160 | 0.078 |
| 1969 | 1 | -- | 40 | 0.959 | 1.298 | 897 | 910 | 0.191 |
| 1970 | 1 | -- | 40 | 0.965 | 1.252 | 1060 | 1070 | 0.112 |
| 1971 | 1 | 2 | 40 | 0.965 | 0.371 | 1000 | 1010 | 0.141 |
| 1972 | 1 | -- | 40 | 0.966 | 1.061 | 1280 | 1290 | 0.050 |
| 1973 | 1 | -- | 140 | 0.966 | 1.347 | 1190 | 1200 | 0.069 |
| 1974 | 1 | D | 140 | 0.967 | 0.848 | 673 | 679 | 0.476 |
| 1975 | 1 | -- | 140 | 0.967 | 1.044 | 1040 | 1050 | 0.123 |
| 1976 | 1 | -- | 140 | 0.968 | 0.904 | 887 | 893 | 0.200 |
| 1977 | 1 | E | 300 | 0.969 | 1.274 | 515 | 519 | 0.738 |
| 1978 | 1 | -- | 430 | 0.969 | 1.542 | 883 | 888 | 0.204 |
| 1979 | 1 | -- | 430 | 0.970 | 0.873 | 919 | 924 | 0.184 |
| 1980 | 1 | -- | 430 | 0.970 | 0.626 | 658 | 662 | 0.503 |
| 1981 | 1 | -- | 430 | 0.971 | 0.905 | 896 | 900 | 0.197 |
| 1982 | 1 | -- | 430 | 0.971 | 0.286 | 966 | 969 | 0.160 |
| 1983 | 1 | -- | 430 | 0.972 | 1.540 | 792 | 795 | 0.291 |
| 1984 | 1 | E | 430 | 0.972 | 1.318 | 812 | 814 | 0.268 |
| 1985 | 1 | -- | 430 | 0.973 | 1.061 | 913 | 915 | 0.188 |
| 1986 | 1 | -- | 430 | 0.973 | 0.818 | 962 | 964 | 0.163 |
| 1987 | 1 | -- | 430 | 0.974 | 2.884 | 1490 | 1490 | 0.031 |
| 1988 | 1 | E | 430 | 0.974 | 0.381 | 610 | 611 | 0.577 |
| 1989 | 1 | -- | 430 | 0.975 | 1.513 | 1170 | 1170 | 0.075 |
| 1990 | 1 | -- | 430 | 0.975 | 1.548 | 1190 | 1190 | 0.071 |
| 1991 | 1 | -- | 430 | 0.975 | 2.052 | 831 | 831 | 0.249 |
| 1992 | 1 | E | 430 | 0.975 | 1.833 | 911 | 911 | 0.191 |
| 1993 | 1 | C | 430 | 0.975 | 1.095 | 962 | 962 | 0.164 |
| 1994 | 1 | C | 430 | 0.975 | 1.417 | 1150 | 1150 | 0.082 |
| 1995 | 1 | CE | 430 | 0.975 | 0.934 | 586 | 586 | 0.619 |
| 1996 | 1 | C | 430 | 0.975 | 0.985 | 820 | 820 | 0.261 |
| 1997 | 1 | C | 430 | 0.975 | 2.405 | 1040 | 1040 | 0.126 |
| 1998 | 1 | CE | 430 | 0.975 | 1.404 | 484 | 484 | 0.792 |
| 1999 | 1 | C | 430 | 0.975 | 1.319 | 792 | 792 | 0.294 |
| 2000 | 1 | CE | 430 | 0.975 | 1.455 | 531 | 531 | 0.721 |
| 2001 | 1 | C | 430 | 0.975 | 1.463 | 890 | 890 | 0.203 |
| 2002 | 1 | C | 430 | 0.975 | 1.399 | 1070 | 1070 | 0.112 |
| 2003 | 1 | C | 430 | 0.975 | 1.136 | 619 | 619 | 0.565 |
| 2004 | 1 | C | 430 | 0.975 | 0.586 | 768 | 768 | 0.333 |
| 2005 | 1 | C | 430 | 0.975 | 0.754 | 414 | 414 | 0.893 |
| 2006 | 1 | CE | 430 | 0.975 | 0.811 | 292 | 292 | 0.970 |
| 2007 | 1 | C | 430 | 0.975 | 1.500 | 927 | 927 | 0.182 |
| 2008 | 1 | C | 430 | 0.975 | 3.615 | 1310 | 1310 | 0.048 |
| 2009 | 1 | C | 430 | 0.975 | 1.424 | 818 | 818 | 0.264 |