In addition to forming a small storage and regulating reservoir, Avalon Dam serves as the diversion dam for the project by diverting water into the Main Canal. The dam is located on the Pecos River 5 miles north of Carlsbad, New Mexico. The dam is a zoned earthfill structure that was constructed by private interests in 1888. The dam washed out in 1893 and, after reconstruction, was washed out again in 1904 by the Pecos River flood. The Reclamation Service rebuilt the dam in 1907. The height of the dam was increased in 1912, and again in 1936. The dam now has a structural height of 60 feet and a volume of 202,000 cubic yards.
The dam now has a structural height of 60 feet and a volume of 202,000 cubic yards. This is an earthfilled structure 1,360 feet long and 53 feet high. There are three spillways and an outlet works.
The original reservoir storage capacity was 7,000 acre-feet; a 1996 resurvey showed a capacity of 4,466 acre-feet at the top of conservation pool.