Observed and urbanization-adjusted annual maximum peak discharge and associated urban fraction and precipitation values at USGS streamgage:
05536207 THORN CREEK TRIBUTARY AT 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
1962 1 -- 0 0.830 0.650 155 165 0.737
1963 1 -- 0 0.833 2.298 127 136 0.861
1964 1 -- 0 0.835 1.817 276 288 0.210
1965 1 -- 0 0.837 1.797 274 286 0.217
1966 1 2 0 0.839 3.894 406 421 0.054
1967 1 -- 0 0.842 1.549 197 206 0.534
1968 1 -- 0 0.844 4.941 1090 1120 0.000
1969 1 -- 0 0.846 1.956 312 322 0.154
1970 1 -- 0 0.848 1.738 238 246 0.352
1971 1 -- 0 0.849 1.579 346 356 0.106
1972 1 -- 0 0.849 1.219 364 375 0.086
1973 1 -- 0 0.849 1.429 244 252 0.324
1974 1 -- 0 0.850 4.242 758 775 0.008
1975 1 -- 0 0.850 1.260 110 116 0.930
1976 1 -- 0 0.851 1.859 179 186 0.633
1977 1 -- 0 0.851 1.998 166 172 0.706