The Horse Mesa Dam is a concrete thin

arch dam An arch dam is a concrete dam that is curved upstream in plan. The arch dam is designed so that the force of the water against it, known as hydrostatic pressure, presses against the arch, causing the arch to straighten slightly and strengthe ...

located in the

Superstition Mountains The Superstition Mountains ( yuf-x-yav, Wi:kchsawa) is a range of mountains in Arizona located to the east of the Phoenix metropolitan area. They are anchored by Superstition Mountain, a large mountain that is a popular recreation destination fo ...

, northeast of Phoenix in

Maricopa County, Arizona Maricopa County is in the south-central part of the U.S. state of Arizona. As of the 2020 United States census, 2020 census, the population was 4,420,568, making it the state's most populous county, and List of the most populous counties in the ...

. The dam is long, high and was built between 1924–27. The dam includes three conventional hydroelectric generating units totaling 32

megawatt The watt (symbol: W) is the unit of power or radiant flux in the International System of Units (SI), equal to 1 joule per second or 1 kg⋅m2⋅s−3. It is used to quantify the rate of energy transfer. The watt is named after James ...

s (MW) and a pumped-storage unit with a capacity of 97 MW. The dam and associated infrastructure were listed on the

National Register of Historic Places The National Register of Historic Places (NRHP) is the United States federal government's official list of districts, sites, buildings, structures and objects deemed worthy of preservation for their historical significance or "great artistic ...

in 2017. A few homes are nearby for temporary employee housing. Its name is derived from when sheep-herders used to graze their saddle and pack animals on the mesa when they were driving their flocks through the area. It has an estimated elevation of above sea level.

Reservoir

The dam forms Apache Lake as it impounds the Salt River. The dam and reservoir are located downstream from the

Theodore Roosevelt Dam Theodore Roosevelt Dam is a dam on the Salt River located northeast of Phoenix, Arizona. The dam is high and forms Theodore Roosevelt Lake as it impounds the Salt River. Originally built between 1905 and 1911, the dam was renovated and expande ...

, and upstream from the

Mormon Flat Dam The Mormon Flat Dam is a dam on the Salt River located Northeast of Phoenix, Arizona. The dam is 380 feet long, 224 feet high and was built between 1923–25. It is named after nearby Mormon Flat, a place where Latter-day Saints (Mormon) settl ...

References

External links

SRP Horse Mesa Dam
* {{Authority control Dams in Arizona Hydroelectric power plants in Arizona Dams on the Salt River (Arizona) Buildings and structures in Maricopa County, Arizona United States Bureau of Reclamation dams Dams completed in 1927 Historic American Engineering Record in Arizona National Register of Historic Places in Maricopa County, Arizona Dams on the National Register of Historic Places in Arizona