Observed and urbanization-adjusted annual maximum peak discharge and associated urban fraction and precipitation values at USGS streamgage:
05531500 SALT CREEK AT WESTERN SPRINGS, 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
1946 1 -- 489 0.222 0.785 775 1420 0.501
1947 1 -- 489 0.233 2.154 1000 1700 0.323
1948 1 -- 489 0.243 1.923 1920 2900 0.052
1949 1 -- 489 0.254 0.725 836 1460 0.471
1950 1 -- 489 0.265 1.233 1360 2100 0.162
1951 1 2 489 0.287 0.346 1200 1850 0.236
1952 1 D 489 0.309 0.725 925 1510 0.440
1953 1 E 489 0.331 1.145 506 947 0.832
1954 1 -- 489 0.353 1.474 1140 1700 0.316
1955 1 -- 489 0.375 3.451 1710 2370 0.108
1956 1 -- 489 0.397 0.831 624 1030 0.781
1957 1 -- 489 0.419 2.686 1020 1480 0.459
1958 1 -- 489 0.441 1.447 778 1160 0.689
1959 1 2 489 0.463 0.379 1200 1630 0.365
1960 1 -- 489 0.485 0.371 1220 1620 0.371
1961 1 -- 489 0.503 1.971 1430 1810 0.258
1962 1 E 489 0.521 0.257 940 1250 0.621
1963 1 E 489 0.539 1.257 585 849 0.889
1964 1 E 489 0.557 0.749 650 899 0.860
1965 1 2 489 0.575 0.129 700 933 0.839
1966 1 -- 489 0.593 1.295 1460 1710 0.310
1967 1 -- 489 0.610 1.398 1350 1580 0.400
1968 1 -- 589 0.628 1.629 1220 1410 0.506
1969 1 -- 589 0.646 0.943 1040 1200 0.659
1970 1 -- 589 0.664 1.431 1110 1250 0.622
1971 1 DE 589 0.675 0.355 739 868 0.880
1972 1 -- 589 0.686 1.311 1790 1890 0.225
1973 1 -- 589 0.697 0.811 1280 1370 0.532
1974 1 -- 589 0.708 1.053 1160 1240 0.629
1975 1 -- 589 0.719 0.992 1600 1650 0.346
1976 1 D 589 0.731 1.050 1460 1500 0.447
1977 0 E 4590 0.742 1.185 1000 1030 0.781
1978 2 E 4590 0.753 1.303 1150 1140 0.708
1979 2 -- 4590 0.764 0.765 1930 1840 0.243
1980 2 E 4590 0.775 0.712 1370 1310 0.575
1981 2 E 5127 0.778 1.794 1450 1380 0.528
1982 2 -- 5127 0.781 0.360 1330 1270 0.608
1983 2 -- 5699 0.784 1.628 2070 1930 0.209
1984 2 -- 5798 0.787 0.552 1040 995 0.803
1985 2 -- 6016 0.789 1.320 1850 1730 0.297
1986 0 -- 6852 0.792 0.836 1330 1260 0.614
1987 3 -- 6852 0.795 2.486 3540 3290 0.032
1988 3 -- 6852 0.798 0.840 1180 1120 0.720
1989 3 -- 6898 0.801 1.445 1360 1280 0.596
1990 3 -- 7768 0.804 1.820 2320 2150 0.155
1991 3 -- 7768 0.805 2.010 1760 1640 0.354
1992 3 E 7768 0.807 0.971 1140 1070 0.752
1993 3 C 7768 0.808 0.652 1160 1090 0.741
1994 3 C 7768 0.809 2.206 1520 1420 0.505
1995 3 C 7768 0.810 0.197 1470 1370 0.536
1996 3 C 8343 0.812 0.751 1650 1530 0.429
1997 3 C 8343 0.813 2.549 2510 2310 0.122
1998 0 C 16643 0.814 0.640 1470 1390 0.522
1999 0 C 16643 0.816 1.468 1550 1490 0.456
2000 0 C 16643 0.817 1.436 1520 1490 0.457
2001 0 C 16643 0.820 1.099 1280 1280 0.600
2002 0 C 18393 0.824 2.535 2080 2090 0.169
2003 4 C 18393 0.827 1.378 1220 1250 0.616
2004 4 CE 18393 0.830 1.362 1110 1140 0.709
2005 4 CE 18393 0.834 1.018 1390 1420 0.505
2006 4 CE 18393 0.837 0.536 945 963 0.822
2007 4 C 18393 0.841 1.630 1920 1940 0.208
2008 4 C 18393 0.844 3.342 2890 2910 0.048
2009 4 C 18393 0.847 0.824 2080 2090 0.170