Barker dam reservoir was constructed as a ranch stock water pond in a natural basin amongst the granite domes in the high country long before the land was incorporated into Joshua Tree National Park. Many small reservoirs were constructed in the area starting in the 1870s. C.O. Barker and William Shay established a cattle operation that ran in the high valleys throughout the Joshua Tree National Park area. Barker built the fist foundation for Barker dam. In the 1950s by rancher, Bill Keys and his family modified the dam to increase the size of the reservoir. Before the park was established in 1936, ranching outfits and mine operators modified many natural tanks in the streambeds and washes to serve as stock ponds in the park area.