Horseshoe Dam


Horseshoe Dam, on the Verde River 58 miles northeast of Phoenix, is an earthfill structure 202 feet high, with a reservoir capacity of 131,500 acre-feet. Horseshoe Dam was built from 1944-1946 by the Phelps-Dodge Copper Products Corp. for the Salt River Valley Water Users' Association under a water exchange agreement. Spillway gates were added to the dam in 1949 by the city of Phoenix to increase the domestic water supply.  In 1952 the dam was raised 4 feet to elevation 2044. 

Horseshoe Dam was also modified by Reclamation in 1993 to address concerns about its safety in the event of a Probable Maximum Flood or Maximum Credible Earthquake. Modifications included construction of a fuse plug auxiliary spillway with an erodible embankment and a concrete foundation 2,000 feet west of the existing spillway. In addition, a 148,000 cubic-yard stability berm was constructed at the downstream toe of the dam to help stabilize it in the event of an earthquake, and the dam was raised eight feet to enable the spillway to pass the Probable Maximum Flood. To prevent overtopping of the structure from wave action, an additional 4-foot parapet was built on the dam's crest. Other work included modifying the service spillway gates, and construction of an auxiliary spillway, closure dike and training dike. The dam tender facilities were also relocated and the road to the boat ramp upgraded.


RegionFacilities in Lower Colorado | Lower Colorado Home Page
ProjectSalt River
Dam TypeZoned Rockfill Embankment
WatercourseVerde River
Location58 miles northeast of Phoenix, AZ
Original Construction1944-1946
Modified Construction1949, 1952, 1993
National ID NumberAZ10310
Hydrologic Unit Code

Structural Height202.0 ft
Hydraulic Height (Normal Operating Depth at Dam)157.0 ft
Top Parapet (Elevation)2055.0 ft
Spillway Crest Elevation2000.0 ft
Crest Elevation2052.0 ft
Crest Length1652.0 ft (with spillways 1994 ft)
Crest Width16.0 ft
Base Width619 ft
Volume of Dam Construction Materials1,595,780 cu-yds
Streambed at Dam Axis1894.9 ft
Top of Exclusive Flood Control Pool (Elevation)
Top of Joint Use Pool (Elevation)
Top of Active Conservation Pool (Elevation)2026.0 ft
Top of Inactive Conservation Pool (Elevation)
Top of Dead Storage Pool (Elevation)1915.0 ft (Tunnel intake elevation)

Hydraulics & Hydrology
Total Water Storage at Elevation 131,500 af at 2026.0 ft
Maximum Water Surface Elevation2051.9 ft
Normal Water Surface Elevation2026 ft
Spillway Type Gate concrete ogee crest
Service Spillway Capacity at Elevation318,000 cfs at 2051.5 ft
Auxiliary SpillwayYes
Auxiliary Spillway Capacity at Elevation 240,000 cfs at 2051.5 ft
Uncontrolled Spillway Capacity at Elevation 558,000 cfs at 2051.5 ft
Outlet Works Capacity at Elevation2200.0 cfs at 2026.0 ft
Diversion Capacity at Elevation
Drainage Area5630 sq mi
Hydrometeorological Report (HMR)HMR 49
Probable Maximum Flood (PMF) Report

Contact Information
TitleArea Office Manager
OrganizationPhoenix Area Office
Address6150 West Thunderbird Road
CityGlendale, AZ 85306-6200
Phone (Fax)623 773-6480
Phone (Office)623 773-6200
OrganizationArea Office Manager
AddressPhoenix Area Office
CityPhoenix, AZ 85306-6200
Phone (Office)623 773-6200

Last updated: Jun 29, 2009