Stream and Station

Most
Probable
Forecast
(1000 AF)

Most
Probable
Forecast
(% of Avg)

Reasonable
Maximum
(% of Avg)

Reasonable
Minimum
(% of Avg)

30 Year
(1961-1990)
Avg Runoff
(1000 AF)

COLUMBIA RIVER
Mica Reservoir Inflow, BC

Arrow Lakes Inflow, BC

Birchbank, BC (1)
International Boundary, BC (1)
Grand Coulee, WA (1)

Rock Island Dam blo, WA (1)
The Dalles nr, OR (1)

FEB-SEP
APR-SEP
FEB-SEP
APR-SEP
APR-SEP
APR-SEP
JAN-JUL
APR-SEP
APR-SEP
JAN-JUL
APR-SEP

13500
12900
27900
26500
45800
59500
64800
66500
72500
102000
95100

103
101
104
104
105
100
102
103
103
96
96

112
112
111
111
114
110
112
112
113
106
106

93
91
97
96
95
89
93
93
93
88
86

13170
12730
26800
25540
43800
59730
63280
64850
70480
105900
98980

KOOTENAI RIVER
Libby Reservoir Inflow, MT (1)

Libby, MT (1)
Leonia, ID (1)
Kootenay Lake Inflow, BC

JAN-JUL
APR-SEP
APR-SEP
APR-SEP
APR-SEP

6930
7180
7650
8720
17300

108
106
106
105
104

126
123
125
122
117

91
89
87
89
91

6396
6772
7207
8275
16650

DUNCAN LAKE INFLOW, BC

FEB-SEP
APR-SEP

2330
2240

100
100

116
116

85
84

2319
2238

CLARK FORK RIVER
Missoula abv, MT
Missoula blo, MT
St. Regis, MT (1)
Plains nr, MT (1)
Whitehorse Rapids, ID (1)

APR-SEP
APR-SEP
APR-SEP
APR-SEP
APR-SEP

1210
2240
3070
9680
10900

72
72
75
84
84

105
97
93
99
99

39
47
57
70
70

1681
3099
4095
11470
12910

BLACKFOOT RIVER
Bonner nr, MT

APR-SEP

735

79

110

49

926

BITTERROOT RIVER
Darby nr, MT
at Mouth, MT

APR-SEP
APR-SEP

400
1030

74
73

74
110

74
35

540
1419

N. FORK FLATHEAD RIVER
Columbia Falls nr, MT

APR-SEP

1660

90

115

65

1836

S. FORK FLATHEAD RIVER
Hungry Horse Res in, MT (1)

JAN-JUL
APR-SEP

2180
2130

96
98

115
117

78
78

2269
2184

M. FORK FLATHEAD RIVER
West Glacier nr, MT

APR-SEP

1610

90

116

64

1788

FLATHEAD RIVER
Columbia Falls, MT
Flathead Lake Inflow, MT (1)

APR-SEP
APR-SEP

5570
6500

93
94

112
111

75
77

5960
6926