The U.S. Geological Survey (USGS) Middle Rio Grande Basin Study was a 6-year effort (1995-2001) by the USGS and other agencies to improve the understanding of the hydrology, geology, and land-surface characteristics of the Middle Rio Grande Basin in order to provide the scientific information needed for water-resources management. The Santa Fe Group aquifer system is the main source of municipal water for the region, and the main purpose of the study was to improve the understanding of the water resources of the basin.

In addition to the USGS, many other Federal, State, and local governments and agencies contributed resources to or cooperated in the Middle Rio Grande Basin Study. These governments and agencies include the City of Albuquerque, New Mexico Office of the State Engineer, New Mexico Bureau of Geology and Mineral Resources (NMBGMR), Middle Rio Grande Council of Governments (MRGCOG), and a number of pueblos and other Federal, State, and local agencies.

The Middle Rio Grande Basin, as defined for the study, is the area within the Rio Grande Valley extending from about Cochiti Lake downstream to about San Acacia. It covers approximately 3,060 square miles in central New Mexico, encompassing parts of Santa Fe, Sandoval, Bernalillo, Valencia, Socorro, Torrance, and Cibola Counties, and includes a ground-water basin composed of the Santa Fe Group aquifer system. (It is equivalent to the Albuquerque Basin referred to by other authors.) The climate over most of the basin is semiarid. In 2000, the population of the Middle Rio Grande Basin was about 690,000 or about 38 percent of the population of New Mexico. Currently (2002), water for municipal and domestic supply is almost exclusively from ground water.