Date: March 5, 2009

Data in this release are preliminary. Final data will be provided in the annual report (WDR-US-2009), Water-resources data for the United States.

NOTES TO EDITOR: (1) ft3/s is an abbreviation for cubic feet per second which is the rate of discharge representing a volume of a cubic foot of water passing a given point during one second and is equivalent to 7.48 gallons per second or 448.8 gallons per minute. (2) the "normal" range is 80 to 120 percent of average.

FEBRUARY STREAMFLOWS MOSTLY BELOW NORMAL
RESERVOIR STORAGE MOSTLY NORMAL

At eight long-term U.S. Geological Survey gaging stations, the monthly mean streamflows for the month of February were below normal at five and normal at three. Monthly mean streamflows were below normal at:

The monthly mean streamflows were normal at the Blackfoot River near Bonner, Clark Fork at St. Regis, and Yellowstone River at Billings.

Water storage remained in the normal range at four out of six major hydroelectric reservoirs in Montana: Canyon Ferry Lake, Bighorn Lake, Hungry Horse Reservoir, and Flathead Lake. Monthend storage remained above normal in Lake Koocanusa and below normal in Fort Peck Lake.

For the month of February, water storage at four major irrigation reservoirs was normal at three and below normal at one. Storage at Lima, Clark Canyon, and Fresno Reservoirs was normal; Gibson Reservoir remained below normal.

Untitled Document
Station February monthly mean discharge, in ft3/s 1971-2000 Average discharge, in ft3/s Percent of average
Yaak River near Troy
e124
377
33
Blackfoot River near Bonner
624
637
98
Clark Fork at St. Regis
3,280
3,700
89
Middle Fork Flathead River near West Glacier
415
774
54
Marias River near Shelby
e178
373
48
Rock Creek below Horse Creek, near International Boundary
0.0
6.75
0
Yellowstone River at Corwin Springs
648
867
75
Yellowstone River at Billings
2,630
2,750
96

e, estimated.

Hydroelectric reservoirs

 February contents in acre-feet Percent of capacity Percent of 1971-2000 average
Canyon Ferry Lake
1,543,000
77
102
Fort Peck Lake
10,640,000
56
69
Bighorn Lake
923,500
68
112
Lake Koocanusa
3,574,000
62
179
Hungry Horse reservoir
2,444,000
71
119
Flathead Lake
724,100
40
90

Irrigation reservoirs
Lima Reservoir
35,140
42
95
Clark Canyon Reservoir
117,700
46
82
Gibson Reservoir
37,710
39
76
Fresno Reservoir
48,160
47
93