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

13300
12800
28100
26700
45300
60200
65000
66800
72900
105000
98300

101
101
105
105
103
101
103
103
103
99
99

112
112
114
114
118
117
119
119
120
116
117

90
90
96
95
89
85
87
87
87
82
82

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

6860
7100
7560
8720
16400

107
105
105
105
98

129
126
126
126
115

85
84
83
84
82

6396
6772
7207
8275
16650

DUNCAN LAKE INFLOW, BC

FEB-SEP
APR-SEP

2390
2290

103
102

120
120

86
85

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

1450
2760
3720
10600
11800

86
89
91
92
91

110
109
125
116
115

62
69
57
68
67

1681
3099
4095
11470
12910

BLACKFOOT RIVER
Bonner nr, MT

APR-SEP

865

93

121

66

926

BITTERROOT RIVER
Darby nr, MT
at Mouth, MT

APR-SEP
APR-SEP

505
1310

94
92

118
109

69
76

540
1419

N. FORK FLATHEAD RIVER
Columbia Falls nr, MT

APR-SEP

1700

93

107

78

1836

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

JAN-JUL
APR-SEP

2160
2100

95
96

119
120

72
72

2269
2184

M. FORK FLATHEAD RIVER
West Glacier nr, MT

APR-SEP

1650

92

125

60

1788

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

APR-SEP
APR-SEP

5620
6650

94
96

111
114

78
79

5960
6926