Horseshoe Dam is named for the horseshoe-shaped bend in the Verde River at the dam site.
The dam was built between 1944-46 by the Phelps Dodge Corporation and the Defense Plant Corporation as part of a water exchange arrangement. The water exchange allowed Phelps Dodge to pump SRP's water from the Black River and in return provided SRP with water from Blue Ridge Reservoir and Show Low Lake, both of which are located on the Little Colorado River watershed.
Spillway gates, funded by the city of Phoenix, were added in 1949 to establish water rights for the city's water users. The earthen dam is 144 feet tall and 1,500 feet long, including the spillway. It has no hydroelectric generating capabilities.
A 2012 preliminary survey showed that the reservoir's water storage capacity has been reduced by almost 46,000 acre-feet since its construction. This is due to natural sediment from the Verde River settling at the bottom of the reservoir.
Horseshoe Dam forms Horseshoe Reservoir. Below are some reservoir statistics:
- Length: 5 miles
- Shoreline: 27 miles
- Current Capacity: 98,281 acre-feet (as of 2012)
- Surface acreage when full: 2,722 acres
- Maximum depth: 77 feet