San Juan - Chama Project

The San Juan – Chama Project was proposed as a way to deliver water to inhabitants in Southern New Mexico and on June 13, 1962 Congress passed the Public Law 87-483 which was then signed by President John F. Kennedy. Public Law 87-483 was implemented as an amendment to the Colorado River Storage Act of 1956 (CRS) and allowed for the diversion of water, from the natural flow in the Colorado River, into the Rio Grande Basin.

The Diversion Project has three dams and three tunnels that span 28 miles from the Blanco Basin in Colorado to the Azotea Outlet on Jicarilla Apache land just southwest of the Village of Chama in New Mexico. Once the water exits the Azotea Outlet, it flows down Willow Creek before being deposited in Heron Reservoir

While multiple phases of this project were proposed only Phase One was actualized and that phase is the San Juan – Chama Project that transports the diverted water and annual storage capacity of 110,000 acres per foot (ac-ft).  Annually, there is approximately 96,200 ac-ft that is diverted and contractually reserved for various cities and tribes. Public Law 87-483 also stipulates that the volume of water diverted cannot exceed 270,000 ac-ft per year or 1,350,000 ac-ft over a ten-year span.

Since construction on the diversions and tunnels were finished, many projects have been conducted on the water in the San Juan - Chama region. Most projects have centered on the water quality and the supply.

Volumes Contracted
City of Albuquerque48,200 ac-ft
MRGCD20,900 ac-ft
Jicarilla Apache Tribe6,500 ac-ft
City of Santa Fe5,605 ac-ft
Cochiti Reservoir Recreation Pool5,000 ac-ft
Los Alamos County1,200 ac-ft
Pojoaque Valley Irrigation District1,030 ac-ft
City of Espanola1,000 ac-ft
City of Belen500 ac-ft
Town of Taos400 ac-ft
Village of Los Lunas400 ac-ft
Town of Bernalillo400 ac-ft
Village of Red River60 ac-ft
Twining Water and Sanitation District15 ac-ft
Acres per foot
Blanco Diversion Dam520 CFS
Blanco Tunnel520 CFS
Little Oso Diversion Dam
150 CFS
Oso Tunnel550 CFS
Oso Diversion Dam650 CFS
Azotea Tunnel950 CFS
Cubic feet per second


  • Falk, Sarah E., et al. Water Quality, Streamflow Conditions, and Annual Flow-Duration Curves for Streams of the SanJuan - Chama Project, Souther Colorado and Northern New Mexico, 1935-2010. U.S. Geological Survey Scientific Investigations, May 2013.
  • Glaser, Leah S. San Juan - Chama Project. Bureau of  Reclamation.
  • Gould, Jaci. San Juan - Chama Project Water Use. 1999.
  • Langman, Jeff B., and Scott K. Anderholm. Effects of Reservoir Installation, San Juan-Chama Project Water, and Reservoir Operations on Streamflow and Water Quality in the Rio Chama and Rio Grande, Northern and Central New Mexico, 1938-2000.
  • Project History: San Juan - Chama Project, Colorado - New Mexico. Volume XV, U.S. Department of the Interior, Bureau of Reclamation, 1977.
  • Whipple, John. San Juan - Chama Project Water Supply. New Mexico Interstate Stream Commission, July 2007.