Pathfinder Dam and Reservoir The Pathfinder dam and reservoir is located about three miles below the junction of the Sweetwater with the North Platte near the old Overland Trail, and is named in honor of John C. Fremont, who was wrecked at almost this point in an attempt to float down to the Missouri. The dam is 100 feet thick at the bottom, 10 feet wide at the top, and 215 feet high, built of solid masonry, is situated in a deep gorge of solid granite. No water ever flows over the dam, the overflow being through a specially constructed spillway cut in the solid rock. The reservoir extends twenty miles up the North Platte and fifteen miles up the Sweetwater and has a capacity of about 326 billion gallons, enough to cover one million acres to a depth of one foot. It collects the flood waters of the

HISTORY OF WESTERN NEBRASKA

river and stores them until such time as they are needed for irrigation. By storing the flood waters in this and other reservoirs the Xorth Platte river will supply more water than will ever be needed fur all the lands that can be watered from it.

Interstate Canal

Just below the mouth of Whalen canyon, and about eight miles up the river from the site of old Fort Laramie, is a diversion dam of concrete 325 feet long with an extreme height of 35 feet, and from the south end of the concrete extends an earthen embankment 2,000 feet long with a maximum height of 18 feet. This check raises the water of the river about 13 feet. The interstate canal heads here with a capacity of 1,400 cubic feet of water per second, and at the forty-fifth mile the capacity is 1,200 cubic feet of water per second.