Observed and urbanization-adjusted annual maximum peak discharge and associated urban fraction and precipitation values at USGS streamgage:
05535500 WF OF NB CHICAGO RIVER AT NORTHBROOK 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 |
| 1953 | 1 | E | 0 | 0.251 | 0.651 | 86 | 197 | 0.961 |
| 1954 | 1 | -- | 0 | 0.281 | 1.608 | 411 | 516 | 0.308 |
| 1955 | 1 | -- | 0 | 0.311 | 0.786 | 404 | 500 | 0.343 |
| 1956 | 1 | E | 0 | 0.341 | 1.198 | 199 | 294 | 0.828 |
| 1957 | 1 | -- | 0 | 0.371 | 1.873 | 930 | 956 | 0.035 |
| 1958 | 1 | -- | 0 | 0.401 | 0.211 | 159 | 245 | 0.921 |
| 1959 | 1 | -- | 0 | 0.431 | 1.067 | 366 | 419 | 0.524 |
| 1960 | 1 | -- | 0 | 0.461 | 0.387 | 275 | 328 | 0.754 |
| 1961 | 1 | -- | 0 | 0.477 | 1.405 | 502 | 516 | 0.304 |
| 1962 | 1 | -- | 0 | 0.493 | 0.246 | 428 | 451 | 0.453 |
| 1963 | 1 | -- | 0 | 0.509 | 1.103 | 350 | 375 | 0.633 |
| 1964 | 1 | -- | 0 | 0.525 | 1.816 | 298 | 327 | 0.755 |
| 1965 | 1 | -- | 0 | 0.541 | 0.487 | 285 | 312 | 0.790 |
| 1966 | 1 | D | 0 | 0.557 | 1.335 | 390 | 391 | 0.593 |
| 1967 | 1 | -- | 0 | 0.573 | 1.532 | 712 | 644 | 0.152 |
| 1968 | 1 | -- | 0 | 0.590 | 1.225 | 397 | 384 | 0.608 |
| 1969 | 1 | -- | 0 | 0.606 | 1.284 | 634 | 562 | 0.227 |
| 1970 | 1 | -- | 0 | 0.622 | 1.321 | 423 | 393 | 0.587 |
| 1971 | 1 | D | 0 | 0.635 | 0.389 | 358 | 338 | 0.729 |
| 1972 | 1 | -- | 0 | 0.648 | 0.683 | 680 | 577 | 0.208 |
| 1973 | 1 | -- | 0 | 0.662 | 1.389 | 674 | 566 | 0.222 |
| 1974 | 1 | -- | 0 | 0.675 | 1.023 | 557 | 477 | 0.397 |
| 1975 | 1 | D | 0 | 0.688 | 0.981 | 534 | 453 | 0.448 |
| 1976 | 1 | -- | 0 | 0.702 | 0.931 | 600 | 496 | 0.350 |
| 1977 | 1 | E | 0 | 0.715 | 1.182 | 175 | 173 | 0.976 |
| 1978 | 1 | -- | 0 | 0.728 | 1.173 | 569 | 462 | 0.430 |
| 1979 | 1 | -- | 0 | 0.741 | 0.870 | 602 | 479 | 0.390 |
| 1980 | 1 | -- | 0 | 0.755 | 0.756 | 582 | 459 | 0.436 |
| 1981 | 1 | -- | 0 | 0.759 | 0.934 | 636 | 495 | 0.351 |
| 1982 | 1 | -- | 0 | 0.762 | 2.047 | 1070 | 807 | 0.064 |
| 1983 | 1 | -- | 0 | 0.766 | 1.506 | 744 | 566 | 0.222 |
| 1984 | 1 | D | 0 | 0.770 | 1.282 | 646 | 497 | 0.347 |
| 1985 | 1 | -- | 0 | 0.774 | 0.759 | 666 | 508 | 0.318 |
| 1986 | 1 | -- | 0 | 0.778 | 0.789 | 698 | 528 | 0.278 |
| 1987 | 1 | -- | 0 | 0.781 | 3.004 | 1190 | 879 | 0.046 |
| 1988 | 1 | -- | 0 | 0.785 | 0.272 | 346 | 277 | 0.863 |
| 1989 | 1 | -- | 0 | 0.789 | 1.681 | 536 | 409 | 0.547 |
| 1990 | 0 | -- | 525 | 0.793 | 2.327 | 719 | 591 | 0.195 |
| 1991 | 0 | -- | 525 | 0.796 | 2.279 | 446 | 416 | 0.532 |
| 1992 | 0 | CE | 1100 | 0.800 | 2.062 | 425 | 438 | 0.484 |
| 1993 | 2 | C | 1100 | 0.803 | 0.536 | 418 | 474 | 0.403 |
| 1994 | 2 | C | 1100 | 0.806 | 2.696 | 767 | 845 | 0.052 |
| 1995 | 2 | C | 1100 | 0.810 | 1.393 | 390 | 441 | 0.477 |
| 1996 | 2 | C | 1100 | 0.813 | 0.564 | 570 | 629 | 0.165 |
| 1997 | 2 | C | 1100 | 0.817 | 2.741 | 507 | 559 | 0.231 |
| 1998 | 2 | CE | 1100 | 0.820 | 1.541 | 374 | 419 | 0.526 |
| 1999 | 2 | C | 1100 | 0.823 | 1.418 | 522 | 572 | 0.216 |
| 2000 | 2 | C | 1100 | 0.827 | 1.270 | 361 | 402 | 0.565 |
| 2001 | 2 | C | 1100 | 0.836 | 2.877 | 624 | 673 | 0.133 |
| 2002 | 2 | C | 1100 | 0.845 | 3.666 | 848 | 902 | 0.042 |
| 2003 | 2 | CE | 1100 | 0.855 | 1.011 | 369 | 398 | 0.574 |
| 2004 | 2 | C | 1100 | 0.864 | 1.421 | 560 | 590 | 0.196 |
| 2005 | 2 | C | 1100 | 0.873 | 0.535 | 300 | 319 | 0.773 |
| 2006 | 2 | CE | 1100 | 0.883 | 0.801 | 308 | 323 | 0.763 |
| 2007 | 2 | C | 1100 | 0.892 | 2.805 | 670 | 687 | 0.123 |
| 2008 | 2 | C | 1100 | 0.901 | 5.144 | 637 | 648 | 0.151 |
| 2009 | 2 | C | 1100 | 0.910 | 1.418 | 421 | 425 | 0.512 |