FLOOD04028

• County: Statewide
• Community: State of Montana
• Stream Name: Upper Missouri River
• Basin: Statewide
• Title: Report of the Flood of June 1964 in the Upper Missouir River Basin in Montana
• Date: 10/1/1964
• Prepared By: US Army Corps of Engineers
• Floodplain - Doc Type: Flood Documentation Report

northwestward into Canada and ,across the Conti.nental Divide into the
Flathead River Basin. It covered all the mountain region west and
northwest of Great Falls and extended over the plains area, both
southeast and northeast of Great Falls.

b. Sun River-Basin. Severe flooding was experienced throughout
the Sun River Basin. Flooding began earJ,y on 8 June in the headwaters
and the river crested at its mouth in Great Falls at midnight 9-10 June.
Urban areas of Augusta, Sun River, Vauglm, Manchester, and Great Falls
sustained extensive damage from flood stages that exceeded anything
experienced in the past, reaching to the rooftops 'of many homes.

c. Marias River Basin. Flooding in the Marias River Basin was
equally widespread and severe. Flooding was experienced along the
entire length of the Teton River, a major tributary of the Marias River.
Floodwaters from the Teton River and a tributary, Spring Creek, combined
on 8 June to flood the entire toWn of Chouteau except for a small 2 or 3
block area. Other urban areas situated along the Teton River are located
on high ground and escaped the onslaught of the flood. Flooding on the
Marias River was limited to the reach upstream from Tiber Reservoir.
PonderaCou1ee which enters below Tiber Dam an!i all of the headwater
streams of the Marias River experienced flooding. Damages in the basin
were compounded by failure of two private irrigation dams on 8 June.
__Swift D~on Birch Creek released in excess of 30,000 acre-feet of 7
stored water and Lower Two Medicine Dam on Two Medicine Creek added over ~
20,000 acre-feet of iltorea:'w!i-terto'tiie flood when they failed. Also,
two small stock water dams located north of Shelby failed on 11 June
releasing approximateJ,y 35 acre-feet of water which caused moderate
flooding in the city of Shelby.

d. Miscellaneous Drainage Basins. Minor to moderate flooding was
experienced along the Missouri River and minor tributaries frOm Canyon
Ferry Dam to Fort Benton and in the Milk River, St. Mary River, Judith
River, Musselshell River, Dearborn River, and Belt Creek Basins~ Also,
minor -Hooding and- ;Levee de.mage was sustained along the Jefferson- and
Madison Rivers, two of the three streams ,which jo:l.n to form the Missouri
River. High water was experienced on the other headwater stream of the
Missouri River, the. Gallatin River, but no flood damage was reported.

17. COLLECTION OF BASIC HYDROIOOIC DATA

a. Hydrological information was gathered, during and following
the flood, by cooperating agencies of Federal, state, and municipal
Gov'ernments. The U. S. Weather Bureau collected rainfall data from its
network stations, which was supplemented by a "bucket" survey of the storm
area utilizing personnel from the Corps of Engineers, U. S. Bureau of
Reclamation, U. S. Weather Bureau, and U. S. Forest Service. Discharge
information 'was collected during the flood by the U. S. Geological Survey
and in addition it organized and is carrying out a comprehensive program

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