Observed and urbanization-adjusted annual maximum peak discharge and associated urban fraction and precipitation values at USGS streamgage:
05530600 DES PLAINES RIVER AT RIVER GROVE, 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
1960 1 -- 6822 0.250 0.542 3620 4970 0.219
1961 1 -- 6822 0.258 1.330 1280 2060 0.859
1962 1 -- 7316 0.265 0.003 2850 4020 0.393
1963 1 -- 7316 0.273 1.315 1550 2370 0.797
1964 1 -- 7533 0.281 0.758 1540 2330 0.804
1965 1 -- 7533 0.288 0.512 2100 3000 0.643
1966 1 -- 7533 0.296 1.174 2800 3850 0.432
1967 1 -- 7533 0.303 1.500 3620 4760 0.251
1968 1 -- 7533 0.311 0.988 2050 2870 0.676
1969 1 -- 7573 0.318 1.358 2880 3860 0.429
1970 1 -- 7573 0.326 1.537 3600 4640 0.269
1971 1 -- 7573 0.333 0.085 2400 3220 0.588
1972 1 -- 8473 0.341 1.087 3600 4590 0.279
1973 1 -- 8573 0.348 1.373 3100 4000 0.397
1974 1 -- 8573 0.355 0.603 2880 3720 0.461
1975 1 -- 8573 0.362 0.790 2890 3700 0.465
1976 1 -- 8573 0.370 1.183 3300 4150 0.366
1977 1 -- 8733 0.377 1.071 1290 1800 0.907