Observed and urbanization-adjusted annual maximum peak discharge and associated urban fraction and precipitation values at USGS streamgage:
05536238 BUTTERFIELD CREEK NEAR LINCOLN ESTATES, 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
1961 1 -- 0 0.070 1.619 248 337 0.151
1962 1 -- 0 0.073 0.246 71 114 0.848
1963 1 4B 0 0.075 0.246 44 78 0.940
1964 1 -- 0 0.078 0.867 61 101 0.890
1965 1 -- 0 0.081 0.948 132 191 0.550
1966 1 -- 0 0.083 1.582 201 275 0.264
1967 1 -- 0 0.086 1.191 100 150 0.723
1968 1 -- 0 0.088 1.491 372 486 0.047
1969 1 -- 0 0.091 0.492 60 98 0.898
1970 1 -- 0 0.094 1.446 271 360 0.124
1971 1 -- 0 0.109 1.028 30 54 0.975
1972 1 -- 0 0.124 1.247 75 113 0.854
1973 1 -- 0 0.139 1.295 120 165 0.657
1974 1 -- 0 0.154 1.145 299 375 0.106
1975 1 -- 0 0.169 1.134 226 283 0.242
1976 1 -- 0 0.184 1.563 150 193 0.542
1977 1 -- 0 0.199 0.752 210 259 0.309
1978 1 -- 0 0.214 1.169 149 186 0.575
1979 1 -- 0 0.229 0.767 573 654 0.018