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

12200
11800
25300
24100
41700
55100
59300
60700
66900
98700
92200

93
93
94
94
95
92
94
94
95
93
93

112
113
106
106
119
117
122
122
124
122
123

73
72
82
82
72
68
65
66
66
65
63

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

6080
6440
6820
7870
15800

95
95
95
95
95

130
128
125
128
117

60
62
64
62
73

6396
6772
7207
8275
16650

DUNCAN LAKE INFLOW, BC

FEB-SEP
APR-SEP

2180
2100

94
94

113
114

75
74

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

1360
2570
3540
9500
10600

81
83
86
83
82

115
114
137
125
124

47
52
36
41
40

1681
3099
4095
11470
12910

BLACKFOOT RIVER
Bonner nr, MT

APR-SEP

750

81

111

51

926

BITTERROOT RIVER
Darby nr, MT
at Mouth, MT

APR-SEP
APR-SEP

460
1210

85
85

118
115

52
55

540
1419

N. FORK FLATHEAD RIVER
Columbia Falls nr, MT

APR-SEP

1520

83

102

63

1836

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

JAN-JUL
APR-SEP

1860
1790

82
82

118
120

46
45

2269
2184

M. FORK FLATHEAD RIVER
West Glacier nr, MT

APR-SEP

1430

80

125

35

1788

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

APR-SEP
APR-SEP

4850
5670

81
82

103
106

59
58

5960
6926