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COLUMBIA - GRAND COULEE DAM   (GCDW1)
Period Rankings - 1960 to 2014
APR-SEP Normal -- 60110 (KAF)
Rank Year Period Volume
(KAF)
Percent of Normal Exceedance
Probability*
1 1974 88474.10 147 1.818 %
2 1997 88294.97 147 3.636 %
3 1972 85404.26 142 5.455 %
4 2012 82810.00 138 7.273 %
5 1976 81920.80 136 9.091 %
6 2011 78743.00 131 10.909 %
7 1971 77954.04 130 12.727 %
8 1996 75486.72 126 14.545 %
9 1969 74722.00 124 16.364 %
10 1999 74534.72 124 18.182 %
11 1982 74356.03 124 20.000 %
12 1967 74009.00 123 21.818 %
13 1991 73375.53 122 23.636 %
14 1961 72214.00 120 25.455 %
15 1964 70846.00 118 27.273 %
16 1965 69973.00 116 29.091 %
17 1990 69101.64 115 30.909 %
18 1981 68588.25 114 32.727 %
19 2002 68483.23 114 34.545 %
20 1975 68089.58 113 36.364 %
21 1978 67771.78 113 38.182 %
22 2014 66101.59 110 40.000 %
23 2013 65121.00 108 41.818 %
24 1983 63879.35 106 43.636 %
25 1968 63755.00 106 45.455 %
26 2006 63719.94 106 47.273 %
27 1966 63228.00 105 49.091 %
28 1962 63098.00 105 50.909 %
29 2008 62764.56 104 52.727 %
30 1984 61660.49 103 54.545 %
31 2000 61539.89 102 56.364 %
32 1980 61149.47 102 58.182 %
33 2007 59675.67 99 60.000 %
34 1998 58686.29 98 61.818 %
35 1963 58517.00 97 63.636 %
36 1986 57679.84 96 65.455 %
37 1989 57565.64 96 67.273 %
38 1995 57341.10 95 69.091 %
39 1985 54722.55 91 70.909 %
40 1970 54718.00 91 72.727 %
41 2004 54259.75 90 74.545 %
42 1993 52691.82 88 76.364 %
43 1979 52482.46 87 78.182 %
44 2003 52407.76 87 80.000 %
45 1994 51883.03 86 81.818 %
46 2005 51724.41 86 83.636 %
47 2010 51372.41 85 85.455 %
48 2009 50989.86 85 87.273 %
49 1988 50917.33 85 89.091 %
50 1987 50128.10 83 90.909 %
51 1973 47144.63 78 92.727 %
52 1992 45644.81 76 94.545 %
53 1977 41230.32 69 96.364 %
54 2001 39832.82 66 98.182 %

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