Dug in 1868 in a pick-and-shovel operation by the Lombardy Irrigation Company, whose officers were N.M.C. Patterson, W.F. Smith, and T. Watkins, the Lombardy Irrigation Ditch channeled water to irrigate over 800 acres and, over its 2-mile length, furnished power for a cotton gin and shingle, grist, and flour mills. The settlement that grew up in the area was known as "The Ditch" until a post office was established in 1875, when it was named Rio Frio ("Cold River"). For a century the ditch irrigated the lands of families of two original company officers.