Navajo Lake, Reservoir in northwestern New Mexico, US.

Navajo Lake is a reservoir on the San Juan River in San Juan and Rio Arriba counties, New Mexico, with a portion reaching into Archuleta County, Colorado. It is held back by the earth- and rock-filled Navajo Dam, 3,800 feet long and 400 feet high, completed in 1962. The lake covers 15,600 acres, runs over 25 miles long and lies at up to 6,085 feet elevation.

The Navajo Dam was built in the 1960s to create this reservoir as part of a major water management project for the San Juan River. The project permanently changed the landscape and reshaped settlement patterns across the region.

The reservoir flooded one of the Navajos' most sacred sites, and the dam's creation forced hundreds of families from four communities — Los Arboles, Los Pinos, Rose and Los Martinez — some of whom had lived there for 80 to 90 years. The lake now lies within Navajo Lake State Park in New Mexico and Navajo State Park in Colorado.

Navajo Lake lies on the San Juan River about 48 km east of Farmington, with shorelines in both New Mexico and Colorado; the New Mexico side near the dam and the river below it fall within Navajo Lake State Park, while the Colorado portion is Navajo State Park. The reservoir is over 40 km long, so plan for driving between access points rather than walking the shore.

The reservoir's 1.7 million acre-feet of water submerged one of the Navajos' most sacred sites, and about 200 families from the communities of Los Arboles, Los Pinos, Rose and Los Martinez had to leave homes where some had lived for 80 to 90 years.