A dam is a barrier that stops or restricts the flow of surface water or underground streams. Reservoirs created by dams not only suppress floods but also provide water for activities such as irrigation, human consumption, industrial use, aquaculture, and navigability. Hydropower is often used in conjunction with dams to generate electricity. A dam can also be used to collect or store water which can be evenly distributed between locations. Dams generally serve the primary purpose of retaining water, while other structures such as floodgates or levees are used to manage or prevent water flow into specific land regions.
An arch bridge is a bridge with abutments at each end shaped as a curved arch. Arch bridges work by transferring the weight of the bridge and its loads partially into a horizontal thrust restrained by the abutments at either side. A viaduct may be made from a series of arches, although other more economical structures are typically used today.
A diversion dam is a dam that diverts all or a portion of the flow of a river from its natural course. Diversion dams do not generally impound water in a reservoir; instead, the water is diverted into an artificial water course or canal, which may be used for irrigation or return to the river after passing through hydroelectric generators, flow into a different river or be itself dammed forming an onground or groundwater reservoir or a storm drain.
The St. Francis Dam was a concrete gravity dam located in San Francisquito Canyon in northern Los Angeles County, California that was built between 1924 and 1926 to serve the city of Los Angeles's growing water needs. It failed catastrophically in 1928 due to a defective soil foundation and design flaws, unleashing a flood that claimed the lives of at least 431 people. The collapse of the dam is considered to have been one of the worst American civil engineering disasters of the 20th century, and remains the 3rd-greatest loss of life in California's history, exceeded only by the 1906 San Francisco earthquake and fire and the Great Flood of 1862.
The Mountain Dell Dam provides a water equalizing and storage reservoir for Salt Lake City, Utah located 10 miles (16 km) east of the city in northeastern Salt Lake County, near Interstate 80 in Parley's Canyon.
The Blue Mountains Dams are a series of six dams in the Blue Mountains which supply water to the Blue Mountains and Sydney, Australia. The Dams are managed by the WaterNSW. Water in this scheme may be supplemented from the Fish River Scheme.
The Contra Dam, commonly known as the Verzasca Dam and the Locarno Dam, is an arch dam on the Verzasca River in the Val Verzasca of Ticino, Switzerland. The dam creates Lago di Vogorno 2 km (1.2 mi) upstream of Lake Maggiore and supports the 105 MW Verzasca hydroelectric power station. It was constructed between 1961 and 1965 and starting shortly after its reservoir was filled, a series of earthquakes related to its water load occurred until 1971. The dam is owned and operated by Verzasca SA and is the fourth tallest in Switzerland.
Morrow Point Dam is a 468-foot-tall (143 m) concrete double-arch dam on the Gunnison River located in Colorado, the first dam of its type built by the U.S. Bureau of Reclamation. Located in the upper Black Canyon of the Gunnison, it creates Morrow Point Reservoir, and is within the National Park Service-operated Curecanti National Recreation Area. The dam is between the Blue Mesa Dam (upstream) and the Crystal Dam (downstream). Morrow Point Dam and reservoir are part of the Bureau of Reclamation's Wayne N. Aspinall Unit of the Colorado River Storage Project, which retains the waters of the Colorado River and its tributaries for agricultural and municipal use in the American Southwest. The dam's primary purpose is hydroelectric power generation.
A buttress dam or hollow dam is a dam with a solid, water-tight upstream side that is supported at intervals on the downstream side by a series of buttresses or supports. The dam wall may be straight or curved. Most buttress dams are made of reinforced concrete and are heavy, pushing the dam into the ground. Water pushes against the dam, but the buttresses are inflexible and prevent the dam from falling over.
Buffalo Bill Dam is a concrete arch-gravity dam on the Shoshone River in the U.S. state of Wyoming. It is named after the famous Wild West figure William "Buffalo Bill" Cody, who founded the nearby town of Cody and owned much of the land now covered by the reservoir formed by its construction. The dam is part of the Shoshone Project, successor to several visionary schemes promoted by Cody to irrigate the Bighorn Basin and turn it from a semi-arid sagebrush-covered plain to productive agricultural land. Known at the time of its construction as Shoshone Dam, it was renamed in 1946 to honor Cody.
The Bakhtiari Dam is an arch dam currently under construction on the Bakhtiari River within the Zagros Mountains on the border of Lorestan and Khuzestan Provinces, Iran. At a planned height of 325 metres (1,066 ft), it will be the world's tallest dam once completed and withhold the second largest reservoir in Iran after the Karkheh reservoir. The main purpose of the dam is hydroelectric power production and it will support a 1,500 MW power station. By trapping sediment, the dam is also expected to extend the life of the Dez Dam 50 km (31 mi) downstream.
The Tsankov Kamak Hydroelectric Power Plant, also Tsankov Kamak HPP, comprises an arch dam and hydroelectric power plant (HPP) on the territory of the village of Mihalkovo, southwestern Bulgaria. It is situated on the Vacha River in Smolyan Province, on the borders of Pazardzhik Province and Plovdiv Province, roughly 40 kilometres (25 mi) southwest of Plovdiv and downstream (north) of the town of Devin. It is a part of the Dospat–Vacha Hydropower Cascade (500.2 MW) development of the Vacha River involving five dams and seven power stations in the provinces of Smolyan, Plovdiv and Pazardzhik, 250 kilometres (160 mi) southeast of the capital Sofia. The other four dams are Dospat, Teshel, Vacha and Krichim.
The Daniel-Johnson dam, formerly known as Manic-5, is a multiple-arch buttress dam on the Manicouagan River that creates the annular Manicouagan Reservoir. The dam is composed of 14 buttresses and 13 arches and is 214 km (133 mi) north of Baie-Comeau in Quebec, Canada. The dam was constructed between 1959 and 1970 for the purpose of hydroelectric power production and supplies water to the Manic-5 and Manic-5-PA power houses with a combined capacity of 2,660 MW. The dam is 214 m (702 ft) tall, 1,314 m (4,311 ft) long and contains 2,200,000 m3 (2,900,000 cu yd) of concrete, making it the largest dam of its type in the world.
The Glanum Dam, also known as the Vallon de Baume dam, was a Roman arch dam built to supply water to the Roman town of Glanum, the remains of which stand outside the town of Saint-Rémy-de-Provence in Southern France. It was situated south of Glanum, in a gorge that cut into the hills of the Alpilles in the Roman province of Gallia Narbonensis. Dating to the 1st century BC, it was the earliest known dam of its kind. The remains of the dam were destroyed during the construction of a modern replacement in 1891, which now facilitates the supply of water to Saint-Rémy-de-Provence in the Bouches-du-Rhône region of France.
The Dara Dam was a Roman arch dam at Dara in Mesopotamia, a rare pre-modern example of this dam type. The modern identification of its site is uncertain, but may rather point to a common gravity dam.
The Salmon Creek Dam is a concrete arch dam on the Salmon Creek, 3 miles (5 km) northwest of Juneau, Alaska. Built in 1914, it is the world's first constant-angle arch variable radius dam. Since it was built, over 100 such dams have been constructed all over the world. The dam was designated as a National Historic Civil Engineering Landmark by the American Society of Civil Engineers in 2022.
The Pensacola Dam, also known as the Grand River Dam, is a multiple-arch buttress dam located between the towns of Disney and Langley on the Grand River in Mayes County, Oklahoma. The dam is operated by the Grand River Dam Authority and creates Grand Lake o' the Cherokees. After decades of vision and planning, it was constructed between 1938 and 1940 for the purposes of hydroelectric power generation, flood control and recreation. It is Oklahoma's first hydroelectric power plant and is referred to as the longest multiple-arch dam in the world.
Changuinola I Dam, is located in district of Changuinola, in the Province of Bocas del Toro, in the western part of Panama. It is the largest roller-compacted concrete arch-gravity dam in the World.
The Aqua Anio Vetus was an ancient Roman aqueduct, and the second oldest after the Aqua Appia.
The Matahina power station is a hydroelectric power facility in Bay of Plenty in New Zealand on the Rangitaiki River downstream of the Aniwhenua Power Station. The river was dammed to form Lake Matahina from which water is drawn and diverted through the power station before being discharged back into the river. The Matahina dam is the largest earth embankment dam in the North Island of New Zealand.
