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COLUMBIA - GRAND COULEE DAM   (GCDW1)
Period Rankings - 1960 to 2015
APR-SEP Normal -- 60110 (KAF)
Rank Year Period Volume
(KAF)
Percent of Normal Exceedance
Probability*
1 1974 88474.10 147 1.786 %
2 1997 88294.97 147 3.571 %
3 1972 85404.26 142 5.357 %
4 2012 82810.00 138 7.143 %
5 1976 81920.80 136 8.929 %
6 2011 78743.00 131 10.714 %
7 1971 77954.04 130 12.500 %
8 1996 75486.72 126 14.286 %
9 1969 74722.00 124 16.071 %
10 1999 74534.72 124 17.857 %
11 1982 74356.03 124 19.643 %
12 1967 74009.00 123 21.429 %
13 1991 73375.53 122 23.214 %
14 1961 72214.00 120 25.000 %
15 1964 70846.00 118 26.786 %
16 1965 69973.00 116 28.571 %
17 1990 69101.64 115 30.357 %
18 1981 68588.25 114 32.143 %
19 2002 68483.23 114 33.929 %
20 1975 68089.58 113 35.714 %
21 1978 67771.78 113 37.500 %
22 2014 66104.00 110 39.286 %
23 2013 65121.00 108 41.071 %
24 1983 63879.35 106 42.857 %
25 1968 63755.00 106 44.643 %
26 2006 63719.94 106 46.429 %
27 1966 63228.00 105 48.214 %
28 1962 63098.00 105 50.000 %
29 2008 62764.56 104 51.786 %
30 1984 61660.49 103 53.571 %
31 2000 61539.89 102 55.357 %
32 1980 61149.47 102 57.143 %
33 2007 59675.67 99 58.929 %
34 1998 58686.29 98 60.714 %
35 1963 58517.00 97 62.500 %
36 2015 58430.52 97 64.286 %
37 1986 57679.84 96 66.071 %
38 1989 57565.64 96 67.857 %
39 1995 57341.10 95 69.643 %
40 1985 54722.55 91 71.429 %
41 1970 54718.00 91 73.214 %
42 2004 54259.75 90 75.000 %
43 1993 52691.82 88 76.786 %
44 1979 52482.46 87 78.571 %
45 2003 52407.76 87 80.357 %
46 1994 51883.03 86 82.143 %
47 2005 51724.41 86 83.929 %
48 2010 51372.41 85 85.714 %
49 2009 50989.86 85 87.500 %
50 1988 50917.33 85 89.286 %
51 1987 50128.10 83 91.071 %
52 1973 47144.63 78 92.857 %
53 1992 45644.81 76 94.643 %
54 1977 41230.32 69 96.429 %
55 2001 39832.82 66 98.214 %

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