Observed and urbanization-adjusted annual maximum peak discharge and associated urban fraction and precipitation values at USGS streamgage:
04087300 LAKE MICHIGAN TRIBUTARY AT WINTHROP HARBOR, 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
1956 1 -- 0 0.179 0.078 78 187 0.454
1957 1 -- 0 0.195 0.661 51 139 0.749
1958 1 -- 0 0.212 0.004 55 143 0.719
1959 1 -- 0 0.228 1.291 76 176 0.516
1960 1 -- 0 0.245 0.930 145 281 0.124
1961 1 -- 0 0.257 0.877 42 118 0.857
1962 1 -- 0 0.270 0.263 94 199 0.389
1963 1 -- 0 0.282 2.390 30 98 0.937
1964 1 -- 0 0.295 2.008 33 103 0.928
1965 1 -- 0 0.307 0.498 80 171 0.547
1966 1 -- 0 0.320 0.867 95 193 0.422
1967 1 -- 0 0.332 0.675 51 124 0.827
1968 1 -- 0 0.345 1.331 39 107 0.913
1969 1 -- 0 0.357 1.629 355 554 0.011
1970 1 -- 0 0.370 1.247 145 253 0.174
1971 1 -- 0 0.387 1.231 134 233 0.222
1972 1 -- 0 0.405 1.674 282 436 0.022