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.
The Aswan Dam, or more specifically since the 1980s, the Aswan High Dam, is one of the world's largest embankment dams, which was built across the Nile in Aswan, Egypt, between 1960 and 1970. Its significance largely eclipsed the previous Aswan Low Dam initially completed in 1902 downstream. Based on the success of the Low Dam, then at its maximum utilization, construction of the High Dam became a key objective of the government following the Egyptian Revolution of 1952; with its ability to better control flooding, provide increased water storage for irrigation and generate hydroelectricity, the dam was seen as pivotal to Egypt's planned industrialization. Like the earlier implementation, the High Dam has had a significant effect on the economy and culture of Egypt.
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 Tuolumne River flows for 149 miles (240 km) through Central California, from the high Sierra Nevada to join the San Joaquin River in the Central Valley. Originating at over 8,000 feet (2,400 m) above sea level in Yosemite National Park, the Tuolumne drains a rugged watershed of 1,958 square miles (5,070 km2), carving a series of canyons through the western slope of the Sierra. While the upper Tuolumne is a fast-flowing mountain stream, the lower river crosses a broad, fertile and extensively cultivated alluvial plain. Like most other central California rivers, the Tuolumne is dammed multiple times for irrigation and the generation of hydroelectricity.
The Sevier River is a 400-mile (640 km)-long river in the Great Basin of southwestern Utah in the United States. Originating west of Bryce Canyon National Park, the river flows north through a chain of high farming valleys and steep canyons along the west side of the Sevier Plateau before turning southwest and terminating in the endorheic basin of Sevier Lake in the Sevier Desert. It is used extensively for irrigation along its course, with the consequence that Sevier Lake is usually dry.
Dworshak Dam is a concrete gravity dam in the western United States, on the North Fork of the Clearwater River in north central Idaho. In Clearwater County, the dam is located approximately four miles (6 km) northwest of Orofino and impounds the Dworshak Reservoir for flood control and hydroelectricity generation.
A reservoir is an enlarged lake behind a dam. Such a dam may be either artificial, built to store fresh water or it may be a natural formation.
Run-of-river hydroelectricity (ROR) or run-of-the-river hydroelectricity is a type of hydroelectric generation plant whereby little or no water storage is provided. Run-of-the-river power plants may have no water storage at all or a limited amount of storage, in which case the storage reservoir is referred to as pondage. A plant without pondage is subject to seasonal river flows, thus the plant will operate as an intermittent energy source. Conventional hydro uses reservoirs, which regulate water for flood control, dispatchable electrical power, and the provision of fresh water for agriculture.
Auburn Dam was a proposed concrete arch dam on the North Fork of the American River east of the town of Auburn, California, in the United States, on the border of Placer and El Dorado Counties. Slated to be completed in the 1970s by the U.S. Bureau of Reclamation, it would have been the tallest concrete dam in California and one of the tallest in the United States, at a height of 680 feet (210 m) and storing 2,300,000 acre-feet (2.8 km3) of water. Straddling a gorge downstream of the confluence of the North and Middle Forks of the American River and upstream of Folsom Lake, it would have regulated water flow and provided flood control in the American River basin as part of Reclamation's immense Central Valley Project.
The Kenney Dam is a rock-fill embankment dam on the Nechako River in northwestern British Columbia, built in the early 1950s. The impoundment of water behind the dam forms the Nechako Reservoir, which is also commonly known as the Ootsa Lake Reservoir. The dam was constructed to power an aluminum smelter in Kitimat, British Columbia by Alcan, although in the late 1980s the company increased their economic activity by selling excess electricity across North America. The development of the dam caused various environmental problems along with the displacement of the Cheslatta T'En First Nation, whose traditional land was flooded.
The Gillespie Dam is a concrete gravity dam located on the Gila River between the towns of Buckeye and Gila Bend, Arizona. The dam was constructed during the 1920s for primarily irrigation purposes. It was key to the development of a 72,000-acre (29,000 ha) parcel owned by "millionaire" W.S. Gillespie of Tulsa, Oklahoma, initially allowing for irrigation of 10,000 acres (4,000 ha). A portion of the dam failed unexpectedly in 1993 during unusually heavy rains.
The Zarqa River or Jabbok River is the second largest tributary of the lower Jordan River, after the Yarmouk River. It is the third largest river in the region by annual discharge and its watershed encompasses the most densely populated areas east of the Jordan River. It rises in springs near Amman, and flows through a deep and broad valley into the Jordan, at an elevation 1,090 metres (3,580 ft) lower.
The Harbaqa Dam or Kharbaqa Dam was a Roman era Palmyrene gravity dam in the Syrian desert about 70 kilometres (43 mi) southwest from Palmyra on the road to Damascus. The dam, built of rubble, concrete, and dressed with ashlar stones, dates to the first or second century AD. The dam later was used as a water supply for the Umayyad palace of Qasr al-Hayr al-Gharbi.
Sadd el-Kafara was a masonry embankment dam on Wadi al-Garawi 10 km southeast of Helwan in Cairo, Egypt. The dam was built in the first half of the third millennium BC by the ancient Egyptians for flood control and is the oldest dam of such size in the world. Never completed, the dam was under construction for 10–12 years before being destroyed by a flood. It was rediscovered by Georg Schweinfurth in 1885.
The Upper Wardha Dam is an earthfill straight gravity dam across the Wardha River, a tributary of the Godavari River, near Simbhora village in Morshi taluk in Amravati district in the Indian state of Maharashtra. The dam provides multipurpose benefits of irrigation, drinking water supply, flood control and hydropower generation.
The Sweetwater Dam is a dam across the Sweetwater River in San Diego County, California. It is located approximately 12 miles (19 km) east of San Diego, 9 miles (14 km) and borders Bonita to the southwest and La Presa to the northeast. The 108-foot (33 m)-high masonry arch dam impounds 960-acre (390 ha) Sweetwater Reservoir.
The Cheslatta River is a tributary of the Nechako River, one of the main tributaries of the Fraser River, in the Canadian province of British Columbia. It flows through the Nechako Plateau. Before the construction of Kenney Dam in the early 1950s the Cheslatta was a minor tributary of the Nechako. Today the Nechako River is dry above the Cheslatta, which provides all its source water.
The Potomac River basin reservoir projects were U.S. Army Corps of Engineers programs that sought to regulate the flow of the Potomac River to control flooding, to assure a reliable water supply for Washington, D.C., and to provide recreational opportunities. Beginning in 1921 the Corps studied a variety of proposals for an ambitious program of dam construction on the Potomac and its tributaries, which proposed as many as sixteen major dam and reservoir projects. The most ambitious proposals would have created a nearly continuous chain of reservoirs from tidewater to Cumberland, Maryland. The 1938 program was focused on flood control, on the heels of a major flood in 1936. The reformulated 1963 program focused on water supply and quality, mitigating upstream pollution from sewage and coal mine waste.
Qasr Burqu' is a set of ruins and an archaeological site in the badia of eastern Jordan and is the site of one of the earliest of the Umayyad desert castles.
Wadi Rajil is a seasonal stream (wadi) in the Badia region of eastern Jordan and southern Syria. It originates in the Jabal al-Druze and flows south through the harrat al-Sham into the Azraq oasis. One of the major watercourses in the Azraq basin, it drains much of the northern part of the basaltic harrat al-Sham, which is also known as the harrat al-Rajil.
