Altar Valley land ownership patterns are a driving force behind collaborative conservation projects. Around 80% of the watershed is divided between 19 agricultural operations, primarily ranches, ranging from 10,000 to 70,000 acres. The ranches are composed of private or Pima County reserve lands in combination with State Trust land or federal leased land.
The State of Arizona is the largest land owner in the watershed, managing 294,000 acres or 48% of the valley to produce revenue for the Arizona State Trust beneficiaries, including the state’s school system. Most State Trust lands are leased primarily for livestock grazing.
The Buenos Aires National Wildlife Refuge occupies about 20% of the watershed, with a little over 117,000 acres.
A small amount of Coronado National Forest land, around 85,000 acres or 14% of the watershed, is located at the southeastern tip of the valley. The US Bureau of Land Management administers about 24,000 acres or 3.9 % of the watershed, including Baboquivari Peak and Coyote Wilderness areas.
A small portion of Tribal land administered by the Schuk Tauk District of the Tohono O’odham Nation is located on the southern end of the watershed.
Finally, Pima County has emerged as a major partner in the Altar Valley, with ownership and management interest in over 200,000 acres of private and leased land. These lands were purchased by Pima County between 2004 and 2010 in support of the Sonoran Desert Conservation Plan, and are part of Pima County’s Maeveen Behan Conservation Lands System.