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COLUMBIA - GRAND COULEE DAM   (GCDW1)
Period Rankings - 1949 to 2024
 APR-SEP Normal -- 61483 (KAF)
Rank Year Period Volume
(KAF) 		Percent of Normal Exceedance
Probability*
1 1997 88519.60 144 1.299 %
2 2012 82568.18 134 2.597 %
3 1976 81341.61 132 3.896 %
4 2011 78523.83 128 5.195 %
5 1954 77995.60 127 6.494 %
6 1956 77002.29 125 7.792 %
7 1996 75574.85 123 9.091 %
8 1999 74552.10 121 10.390 %
9 1982 74281.22 121 11.688 %
10 1950 74122.91 121 12.987 %
11 1991 73407.01 119 14.286 %
12 1959 72971.13 119 15.584 %
13 1951 71496.70 116 16.883 %
14 1972 68931.36 112 18.182 %
15 2018 68845.71 112 19.481 %
16 1981 68578.00 112 20.779 %
17 2002 68475.53 111 22.078 %
18 1990 68314.68 111 23.377 %
19 2017 67971.04 111 24.675 %
20 2022 67928.23 110 25.974 %
21 1975 67659.76 110 27.273 %
22 1961 67490.31 110 28.571 %
23 1978 67437.83 110 29.870 %
24 2014 66212.52 108 31.169 %
25 2020 66004.04 107 32.468 %
26 1967 65374.69 106 33.766 %
27 2013 65187.83 106 35.065 %
28 1971 63848.86 104 36.364 %
29 1983 63836.01 104 37.662 %
30 2006 63825.61 104 38.961 %
31 1974 63606.21 103 40.260 %
32 1964 63542.91 103 41.558 %
33 1969 63527.95 103 42.857 %
34 1965 62874.17 102 44.156 %
35 2008 62869.22 102 45.455 %
36 1984 61665.36 100 46.753 %
37 1955 61509.14 100 48.052 %
38 2000 61493.18 100 49.351 %
39 1960 61470.95 100 50.649 %
40 1980 61225.89 100 51.948 %
41 1952 61178.06 100 53.247 %
42 2007 59642.20 97 54.545 %
43 1957 59277.90 96 55.844 %
44 1953 58927.07 96 57.143 %
45 1998 58630.22 95 58.442 %
46 1986 57598.57 94 59.740 %
47 1989 57545.62 94 61.039 %
48 1995 57293.57 93 62.338 %
49 1958 56677.79 92 63.636 %
50 1966 56512.63 92 64.935 %
51 1962 56427.48 92 66.234 %
52 2016 55600.01 90 67.532 %
53 1949 55136.94 90 68.831 %
54 1968 54615.08 89 70.130 %
55 1985 54440.37 89 71.429 %
56 2004 54224.11 88 72.727 %
57 2021 53290.46 87 74.026 %
58 1963 52819.73 86 75.325 %
59 1993 52644.88 86 76.623 %
60 1979 52470.87 85 77.922 %
61 2019 52437.83 85 79.221 %
62 2003 52349.59 85 80.519 %
63 1994 51884.36 84 81.818 %
64 2005 51809.16 84 83.117 %
65 2010 51505.69 84 84.416 %
66 2009 51109.37 83 85.714 %
67 2024 50887.21 83 87.013 %
68 1988 50848.37 83 88.312 %
69 1987 50113.12 82 89.610 %
70 2023 48819.30 79 90.909 %
71 2015 45887.84 75 92.208 %
72 1992 45653.54 74 93.506 %
73 1970 42053.35 68 94.805 %
74 1977 41107.65 67 96.104 %
75 2001 39787.47 65 97.403 %
76 1973 34031.38 55 98.701 %

*Exceedance Probability: The probability that a specific seasonal volume will be exceeded.