Middle Rio Grande Project
The Middle Rio Grande Project was authorized by the Congress to improve and stabilize the economy of the Middle Rio Grande Valley by rehabilitation of the Middle Rio Grande Conservancy District facilities and by controlling sedimentation and flooding in the Rio Grande. The Bureau of Reclamation and the Corps of Engineers jointly planned the comprehensive development of the project. Reclamation undertook the rehabilitation of El Vado Dam, rehabilitation of project irrigation and drainage works, and channel maintenance. The Corps of Engineers was assigned the construction of flood control reservoirs and levees for flood protection. The Reclamation project extends along the Middle Rio Grande Valley from the Velarde area south to the backwaters of Elephant Butte Reservoir. It includes maintenance of the Rio Grande in the vicinity of Truth or Consequences, New Mexico. Built originally by the conservancy district, the irrigation features of the project divert water from the river to irrigate up to 89,652 acres of irrigable land. There are 30,000 acres of Indian water right lands within the project. Construction features rehabilitated by Reclamation in addition to El Vado Dam are Angostura, Isleta, and San Acacia Diversion Dams. The Middle Rio Grande Project consists of El Vado Dam and irrigation and drainage facilities in the middle Rio Grande Valley. The project includes river channel maintenance from Velarde, New Mexico southward to Caballo Reservoir. It also includes the Low Flow Conveyance Channel south of San Acacia, New Mexico.
The land between Taos Pueblo and Socorro is the oldest continually settled section of the United States. For centuries, the Pueblo Indians diverted water from the Rio Grande for irrigation. Withe the arrival of the Spanish settlers in the 17th century, a more permanent system of diversions, called acequias, were established. The area was ceded to the United States by Mexico in 1848, but it was not until shortly after the Civil War that all the land capable of being irrigated had been claimed and was being developed. In 1880, a record total of 124,800 acres was irrigated between Cochiti and San Marcial. During the next 40 years, increased water depletion accompanied by increasing sediment loads, floods, and a rising water table forced acreage out of production.
El Vado Dam was rehabilitated by the Bureau of Reclamation in 1954-1955. In 1966, the spillway and outlet works were modified to bypass San Juan-Chama water. Isleta Diversion Dam was rehabilitated in 1955; San Acacia Diversion Dam in 1957; Angostura and Cochiti Diversion Dams in 1958. In 1974-1975, Cochiti Dam was constructed by the Corps of Engineers. Considerable rehabilitation work on canals, laterals, drains, and acequias throughout the project was performed by Reclamation between 1953-1961. Construction of the low-flow conveyance channel between San Acacia Diversion Dam and the Narrows of Elephant Butte began in 1951 and was completed in 1959. Modification of the headworks, for the Socorro Main Canal north at San Acacia Diversion Dam was completed in 1961. The canal was tied into Drain Unit No. 7 Extension and, in turn, to Drain Unit No. 7 system in 1975. River realignment and improvement work by the Bureau of Reclamation between Velarde and the mouth of the Rio Puerco was begun in 1954 and completed in 1962. Annual maintenance continues. The type of soil, and the climate, markets, crop varieties, and irrigation facilities make intensive, diversified farming practices attractive and profitable. Alfalfa, barley, wheat, oats, corn, fruits, and vegetables are the principal crops grown. Rehabilitation of the irrigation system throughout the project has resulted in a more stable water supply. Irrigation water is supplied to about 90,000 acres, including water for the six southern Indian pueblos of Cochiti, Santo Domingo, San Felipe, Santa Ana, Sandia, and Isleta, all of which are served by the Middle Rio Grande Conservancy District. The stabilization of the river channel through clearing, pilot channels, and jetty fields has resulted in the establishment of large wooded riparian areas called the bosque. Previously, large stands of trees were destroyed during heavy runoff years because the river meandered back and forth across the channel from levee to levee. The areas between the cleared floodway and the riverside levees are now filled with a permanent stand of large trees and other dense growths of vegetation. The invasion of nonnative species, as well as the lack of native tree regenertion, is of environmental concern. For specific information on recreational opportunities at El Vado Reservoir click on the name below. El Vado Reservoir The river maintenance program, when coupled with the Corps of Engineers' flood control dams and system of levees, has greatly reduced the threat of uncontrolled flooding in the Middle Rio Grande Valley. Although there is no specific reservoir capacity assigned for flood control. The Middle Rio Grande Project has provided an accumulated $50,760,000 in flood control benefits from 1950 to 1999.
El Vado Reservoir provides supplemental storage for the project. Diversions into the district irrigation system are made at Cochiti Dam and at Angostura, Isleta, and San Acacia Diversion Dams. To effect water savings which help to meet water commitments of the Rio Grande Compact, a permanent conveyance channel was constructed and is maintained between San Acacia Diversion Dam and the Narrows of Elephant Butte Reservoir. River maintenance north of San Acacia Diversion Dam to Velarde, New Mexico, also is carried on as part of the river maintenance program. El Vado Dam, located on the Rio Chama about 160 miles north of Albuquerque, was built by the conservancy district in 1934-1935 and was rehabilitated by the Bureau of Reclamation in 1954-1955. A new outlet works was built by Reclamation in 1965-1966 to accommodate the additional water from the San Juan-Chama Project. The dam embankment is of rolled gravel fill with a steel membrane on the upstream face. The dam is 230 feet high and has a crest length of 1,326 feet. The reservoir has a total capacity of 196,500 acre-feet. There are three diversion dams, all of which have been rehabilitated. Angostura Diversion Dam, serving the Albuquerque Division, consists of a concrete weir section 17 feet high and 800 feet long; Isleta Diversion Dam, serving the Belen Division, is a reinforced concrete structure 21 feet high and 674 feet long with 30 radial gates; and San Acacia Diversion Dam, serving the Socorro Division, is 17 feet high and 700 feet long with 29 radial gates. Lands in the Cochiti Division, previously served by the Cochiti Diversion Dam, now receive their supply directly from Cochiti Dam, a Corps of Engineers flood control dam. Cochiti Diversion Dam was inundated by the construction of Cochiti Dam. The distribution and drainage system is made up of 202 miles of canals, of which about 6 miles are concrete lined; 580 miles of laterals, of which about 4 miles are concrete lined; and 405 miles of open and concrete pipe drains, most of which are open section. A major portion of the work is maintenance of the Rio Grande for a distance of 149 miles to reduce the non beneficial use of water. This maintenance is necessary because of the aggradation in the channel and resulting loss of water by evaporation and transpiration from heavy growths of salt cedar and other plants. Of the 149 miles of maintenance and flood control improvements in the project, there are 18 miles in the Espanola area, 8 miles in the Cochiti, 24 miles in the Albuquerque, 28 miles in the Belen, 37 miles in the Socorro, 33 miles in the San Marcial, and 1 mile in the Truth or Consequences areas. These improvements include clearing of sediment plugs, pilot channeling, jetty installation, and the low-flow channel. Since the late 1980's, alternative means of channel maintenance have been employed as well, with the goal of improving riverine and raparian habitat values. El Vado Dam and river maintenance of the Rio Grande from Velarde to the Narrows of Elephant Butte Reservoir are operated and maintained by the Bureau of Reclamation. Irrigation facilities, including the three diversion dams, are operated by the Middle Rio Grande Conservancy District. Cochiti Dam is operated and maintained by the Corps of Engineers.