Olmos Dam is a

detention dam A detention dam is a dam built to catch surface runoff and stream water flow to regulate the water flow in areas below the dam. Detention dams are commonly used to reduce the damage caused by flooding or to manage the flow rate through a channel. De ...

located in

San Antonio ("Cradle of Freedom") , image_map = , mapsize = 220px , map_caption = Interactive map of San Antonio , subdivision_type = Country , subdivision_name = United States , subdivision_type1= U.S. state, State , subdivision_name1 = Texas , s ...

Texas Texas (, ; Spanish language, Spanish: ''Texas'', ''Tejas'') is a state in the South Central United States, South Central region of the United States. At 268,596 square miles (695,662 km2), and with more than 29.1 million residents in 2 ...

."Dams and Reservoirs in Texas: Historical and Descriptive Information, December 31, 1966," Cleo LaFoy Dowell, Seth Darnaby Breeding, ''Texas Water Development Board'', 1967. p.36 It was built in the 1920s, following the disastrous

September 1921 San Antonio floods In early September 1921, the remnants of a Category 1 hurricane brought damaging floods to areas of Mexico and the U.S. state of Texas, particularly in the San Antonio region. On September 4, a tropical cyclone developed in t ...

. Work began on the dam on January 19, 1925, completed in 1926, and in 1929 a ''cut-off channel'', to allow excess water to bypass the Great Bend in downtown, was completed. Projects, which together have been providing flood control. In the 1970s, improvements were made by the

City of San Antonio ("Cradle of Freedom") , image_map = , mapsize = 220px , map_caption = Interactive map of San Antonio , subdivision_type = Country , subdivision_name = United States , subdivision_type1= State , subdivision_name1 = Texas , subdivision_t ...

and the

San Antonio River Authority In 1917, the voters of Texas, recognizing the necessity of developing and conserving the State's water resources and inspired by devastating floods of 1913 and 1914, passed a Constitutional amendment allowing the Legislature to create special pur ...

. In March 1979, an improvement was made to strengthen and anchor the dam, as well as modifying gate operations, in order to provide an emergency spillway. There are six gates within the dam, two of which are open at all times to a height of . They are rotated once a week. Each gate is controlled via an

actuator An actuator is a component of a machine that is responsible for moving and controlling a mechanism or system, for example by opening a valve. In simple terms, it is a "mover". An actuator requires a control device (controlled by control signal) a ...

that is situated inside the dam's gatehouse. ''

San Antonio Express-News The ''San Antonio Express-News'' is a daily newspaper in San Antonio, Texas. It is owned by the Hearst Corporation and has offices in San Antonio and Austin, Texas. The ''Express-News'' is the third largest newspaper in the state of Texas, with ...

'' history columnist Paula Allen has referred to the dam as "the jewel in the crown of San Antonio’s system of flood control." It has become a "staple structure north of downtown San Antonio." Excavations in the area around Olmos Dam, both prior to the dam's construction in the 1920s and in subsequent excavations such as in 1979, have yielded a good number of Native American artifacts.

References

Buildings and structures completed in 1927 Dams in Texas {{US-dam-stub

See also

References