Fresno Dam, located on the Milk River 14 miles west of Havre, Mont., is a compacted earthfill dam with a structural height of 110 feet and a crest length of 2,070 feet. It contains 2,105,000 cubic yards of material. An overflow-type spillway at the north end of the dam provides for a flow of 51,360 cubic feet per second through the concrete-lined channel. The outlet works discharge a maximum of 2,180 cubic feet per second through two 72-inch steel pipe outlet tubes. A conservation storage of 127,200 acre-feet is impounded in Fresno Reservoir. Provision also is made for flood control benefits.
Fresno Dam is located in a valley, which the Milk River has cut in sandstone and shales of the Judith River formation (Upper Cretaceous). The strata of the Judith River formation dip gently east-word and are frequently of the lenticular nature. Foundation is river silts and gravel in riverbed, irregularly cemented, leaky Fresno sandstone in right abutment; sandstone underlain by impervious and fairly stable Sprague shale in left abutment.