Saguaro Lake, Reservoir in Tonto National Forest, Arizona, United States

Saguaro Lake is a reservoir in the desert of central Arizona with approximately 22 miles of shoreline and water depths reaching 90 feet. The shore features mountains reflected in the water, with boat ramps and beach areas for public use.

The Stewart Mountain Dam was built in 1930 to create this reservoir as a water storage facility for the Salt River system. The lake served as a key infrastructure project to supply water to growing settlements in the region.

The reservoir lies within Tonto National Forest, and its facilities are managed by that authority. The name comes from the saguaro cacti of the surrounding desert, though the sources record no local tradition tied to the lake itself. Anglers come for largemouth bass, carp and rainbow trout.

The lake is accessible via State Route 87 near Mesa and offers multiple boat ramps, the Saguaro del Norte Recreation area, and Butcher Jones Beach. Visitors should prepare for desert heat and sun exposure when spending time on or near the water.

Saguaro Lake is the fourth reservoir on the Salt River, held back by Stewart Mountain Dam at 1,506 feet (459 m) elevation. The lake lies within Tonto National Forest, and its facilities are managed by that authority. Golden algae caused documented fish kills in 2017–2019 and again in 2022.