Observed and urbanization-adjusted annual maximum peak discharge and associated urban fraction and precipitation values at USGS streamgage:
05536210 THORN CREEK NEAR CHICAGO HEIGHTS, IL

Observed annual peak-flood magnitudes were adjusted to 2010 land-use conditions on the basis of panel data regression model with fixed effect analysis. The symbols presented in the figure are: "observed annual peaks", "adjusted annual peaks", and "fraction of urbanization in the watershed"

Legend for Graph

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
1965 1 -- 376 0.523 1.439 684 827 0.621
1966 1 -- 376 0.528 3.139 1520 1750 0.086
1967 1 -- 376 0.534 1.482 670 802 0.647
1968 1 -- 376 0.540 3.775 2040 2290 0.034
1969 1 -- 376 0.546 1.195 437 539 0.883
1970 1 -- 376 0.552 1.540 886 1020 0.432
1971 1 -- 376 0.555 1.393 950 1090 0.374
1972 1 -- 376 0.558 2.427 714 828 0.620
1973 1 -- 376 0.561 1.269 1330 1490 0.153
1974 1 -- 376 0.564 3.206 2220 2440 0.027
1975 1 -- 376 0.567 1.688 667 770 0.681
1976 1 D 376 0.570 1.692 1040 1170 0.306
1977 1 -- 376 0.573 1.708 942 1060 0.399
1978 1 -- 376 0.576 1.393 1070 1190 0.288
1979 1 -- 376 0.579 0.356 1070 1190 0.290