Navajo Lake is a reservoir located in San Juan County and Rio Arriba County in northwestern New Mexico, in the southwestern United States. Portions of the reservoir extend into Archuleta County in southern Colorado. The lake is part of the Colorado River Storage Project, which here manages the upper reaches of the San Juan River, storing and releasing water that is used locally for irrigation, or ultimately reaching the Colorado River in Utah. Water is impounded in Navajo Lake by the earth- and rock-filled Navajo Dam, long and high, completed in 1962. The lake is over long and lies at an elevation of up to .
The construction of the dam and the resulting lake flooded and destroyed one of the Navajos' most sacred sites.
The Lake and associated shoreline areas near the dam in New Mexico and the river shorelines below the dam are part of New Mexico's Navajo Lake State Park, while the Portion of the shoreline and portion of the lake that is located in Colorado make up Navajo State Park which is managed as part of the Colorado State Parks system. The lake has smallmouth bass, black crappie, northern pike, channel catfish, and trout. The waters of Navajo Lake forced hundreds of families to leave their homes and communities. The four communities affected were Los Arboles, Los Pinos, Rose and Los Martinez. The 1.7 million acre-foot reservoir displaced an unknown amount of farms and ranches. It has been estimated that almost 200 families had to move. Some families had been here nearly 80–90 years.