 The construction of this reservoir, which at the time, had a capacity of , ensured a steady water supply for the powerhouse and for irrigation during the summer.A Great Western Power Company subsidiary, the Western Canal Company, would manage the distribution of water to farmers on the lower Feather River near Oroville in Butte County.Between 1919 and 1921, the first Caribou Powerhouse was built on the tributary Butt Creek, and a tunnel was excavated from Lake Almanor to the creek to provide water for the powerhouse.