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

14000
13600
31000
29500
50900
68800
74100
76400
85500
130000
122000

106
107
116
116
116
115
117
118
121
123
123

118
118
125
125
131
131
133
134
138
139
141

96
95
107
106
102
99
101
102
104
106
105

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

7130
7530
7990
9250
18900

111
111
111
112
114

133
132
132
133
131

90
91
89
91
97

6396
6772
7207
8275
16650

DUNCAN LAKE INFLOW, BC

FEB-SEP
APR-SEP

2540
2460

110
110

126
128

92
92

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

2020
3720
4960
13400
14900

120
120
121
117
115

144
140
155
141
140

96
100
87
93
91

1681
3099
4095
11470
12910

BLACKFOOT RIVER
Bonner nr, MT

APR-SEP

1110

120

147

93

926

BITTERROOT RIVER
Darby nr, MT
at Mouth, MT

APR-SEP
APR-SEP

655
1700

121
120

146
136

97
103

540
1419

N. FORK FLATHEAD RIVER
Columbia Falls nr, MT

APR-SEP

2080

113

128

99

1836

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

JAN-JUL
APR-SEP

2530
2480

112
114

134
138

89
90

2269
2184

M. FORK FLATHEAD RIVER
West Glacier nr, MT

APR-SEP

2070

116

130

102

1788

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

APR-SEP
APR-SEP

6800
8100

114
117

136
134

93
99

5960
6926