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.
A gravity dam is a dam constructed from concrete or stone masonry and designed to hold back water by using only the weight of the material and its resistance against the foundation to oppose the horizontal pressure of water pushing against it. Gravity dams are designed so that each section of the dam is stable and independent of any other dam section.
Diamond Valley Lake is a man-made off-stream reservoir located near Hemet, California, United States. It is one of the largest reservoirs in Southern California and one of the newest. It has a capacity of 800,000 acre-feet (990,000,000 m3). The lake nearly doubled the area's surface water storage capacity and provides additional water supplies for drought, peak summer, and emergency needs.
Lake Cumberland is a reservoir in Clinton, Pulaski, Russell, Wayne, and Laurel, counties in Kentucky. The primary reasons for its construction were a means for flood control and the production of hydroelectric power. Its shoreline measures 1,255 miles (2,020 km) and the lake covers 65,530 acres (265 km2) at the maximum power pool elevation. The reservoir ranks 9th in the U.S. in size, with a capacity of 6,100,000 acre-feet (7.5 km3) of water, enough to cover the entire Commonwealth of Kentucky with 3 inches (76 mm) of water. The main lake is 101 miles (163 km) long and over one mile (1.6 km) across at its widest point.
Center Hill Lake is a reservoir in the U.S. state of Tennessee. It is located in Middle Tennessee near Smithville. Created by means of a dam constructed by the U.S. Army Corps of Engineers in 1948, the lake has a dual purpose: electricity production and flood control. Center Hill Dam is 260 ft (79 m) high, and it is composed of concrete and earth structures, with 8 gates that are 50 ft (15 m) wide each. Center Hill Lake is one of four major flood control reservoirs for the Cumberland; the others being Percy Priest Lake, Dale Hollow Reservoir, and Lake Cumberland.
J. Percy Priest Dam is a dam in north central Tennessee at river mile 6.8 of the Stones River, a tributary of the Cumberland. It is located about ten miles (16 km) east of downtown Nashville. The reservoir behind the dam is Percy Priest Lake. It is one of four major flood control reservoirs for the Cumberland; the others being Wolf Creek Dam, Dale Hollow Dam, and Center Hill Dam.
Pomme de Terre Lake is located in southwest Missouri at the confluence of Lindley Creek and the Pomme de Terre River. The lake is located in southern Hickory and northern Polk counties, about 50 miles (80 km) north of Springfield. Its name is the French language word for potato.
Tuttle Creek Lake is a reservoir on the Big Blue River 5 miles (8 km) north of Manhattan, in the Flint Hills region of northeast Kansas. It was built and is operated by the Army Corps of Engineers for the primary purpose of flood control. Secondary functions of the project include release of water stores to maintain barge traffic on the Mississippi River during seasons of drought, maintenance of a multi-use conservation pool for fish and wildlife enhancement and recreation, and release of sufficient water in droughts to maintain water quality for downstream communities.
Hartwell Dam is a concrete and embankment dam located on the Savannah River at the border of South Carolina and Georgia, creating Lake Hartwell. The dam was built by the U.S. Army Corps of Engineers between 1955 and 1962 for the purposes of flood control, hydropower and navigation. The concrete and earthen structure spans 15,840 feet (4,828 m). The concrete section is 1,900 feet (579 m) long and rises 204 feet (62 m) above the riverbed at its apex. The Hartwell Dam currently produces 468 million KWh of electricity annually, has prevented over $40 million in flood damage since completion and also provides recreation, water quality, water supply, along with fish and wildlife management.
Mangrove Creek Dam, a concrete faced rockfill embankment dam, is the primary reservoir for water supply to residents of the Central Coast in New South Wales, Australia.
Roller-compacted concrete (RCC) or rolled concrete (rollcrete) is a special blend of concrete that has essentially the same ingredients as conventional concrete but in different ratios, and increasingly with partial substitution of fly ash for Portland cement. The partial substitution of fly ash for Portland Cement is an important aspect of RCC dam construction because the heat generated by fly ash hydration is significantly less than the heat generated by Portland Cement hydration. This in turn reduces the thermal loads on the dam and reduces the potential for thermal cracking to occur. RCC is a mix of cement/fly ash, water, sand, aggregate and common additives, but contains much less water. The produced mix is drier and essentially has no slump. RCC is placed in a manner similar to paving; the material is delivered by dump trucks or conveyors, spread by small bulldozers or specially modified asphalt pavers, and then compacted by vibratory rollers.
The Canning Dam and reservoir are a major source of fresh water for the city of Perth, Western Australia. The dam is situated on the Darling Scarp and is an impoundment of the Canning River. It is noted for its innovative structural and hydraulic design that was considered to be at the forefront of concrete gravity dam design at the time of construction in from 1933 to its completion 1940.
An embankment dam is a large artificial dam. It is typically created by the placement and compaction of a complex semi-plastic mound of various compositions of soil or rock. It has a semi-pervious waterproof natural covering for its surface and a dense, impervious core. This makes the dam impervious to surface or seepage erosion. Such a dam is composed of fragmented independent material particles. The friction and interaction of particles binds the particles together into a stable mass rather than by the use of a cementing substance.
Alum Creek Lake is a man-made reservoir located in Delaware County, Ohio, United States. It was built in 1974, covers 5 square miles (13 km2), and has a maximum capacity of 134,815 acre-feet (166,292,000 m3).
Mosul Dam, formerly known as Saddam Dam, is the largest dam in Iraq. It is located on the Tigris river in the western governorate of Nineveh, upstream of the city of Mosul. The dam serves to generate hydroelectricity and provide water for downstream irrigation. At full capacity, the structure holds about 11.1 cubic kilometres (2.7 cu mi) of water and provides electricity to the 1.7 million residents of Mosul.
Fontenelle Dam was built between 1961 and 1964 on the Green River in southwestern Wyoming. The 139-foot (42 m) high zoned earthfill dam impounds the 345,360-acre-foot (0.42600 km3) Fontenelle Reservoir. The dam and reservoir are the central features of the Seedskadee Project of the U.S. Bureau of Reclamation, which manages the Fontenelle impoundment primarily as a storage reservoir for the Colorado River Storage Project. The dam suffered a significant failure in 1965, when the dam's right abutment developed a leak. Emergency releases from the dam flooded downstream properties, but repairs to the dam were successful. However, in 1983 the dam was rated "poor" under Safety Evaluation of Existing Dams (SEED) criteria, due to continuing seepage, leading to an emergency drawdown. A concrete diaphragm wall was built through the core of the dam to stop leakage.
John Redmond Reservoir is a reservoir on the Neosho River in eastern Kansas. Built and managed by the U.S. Army Corps of Engineers, it is used for flood control, recreation, water supply, and wildlife management. It borders the Flint Hills National Wildlife Refuge to the northwest.
The Portugués Dam is a roller-compacted concrete thick arch dam on the Portugués River, three miles (5 km) northwest of the city Ponce, in Barrio Tibes, Ponce, Puerto Rico. Construction on the dam began in April 2008, soon after the U.S. Army Corps of Engineers, Jacksonville District awarded the Spanish firm Dragados USA, a division of Grupo ACS, with a $180 million contract in March 2008 to build the dam.
Pressure grouting or jet grouting involves injecting a grout material into otherwise inaccessible but interconnected pore or void space of which neither the configuration or volume are known, and is often referred to simply as grouting. The grout may be a cementitious, resinous, or solution chemical mixture. The greatest use of pressure grouting is to improve geomaterials. The purpose of grouting can be either to strengthen a formation or to reduce water flow through it. It is also used to correct faults in concrete and masonry structures. Since first usage in the 19th century, grouting has been performed on the foundation of virtually every one of the world's large dams, in order to reduce the amount of leakage through the rock, and sometimes to strengthen the foundation to support the weight of the overlying structure, be it of concrete, earth, or rock fill. It is also a key procedure in the creation of post-tensioned prestressed concrete, a material used in many concrete bridge designs, among other places.
San Antonio Dam is an embankment flood control and debris dam on San Antonio Creek in San Bernardino County, California, about 5 miles (8.0 km) north of Ontario. The dam was authorized by the Flood Control Acts of 1936 and 1938 as part of a major program to provide flood protection in the Santa Ana River system. Construction began in April 1952 and finished in May 1956. The dam controls runoff from a rugged catchment area of 27 square miles (70 km2) in the San Gabriel Mountains.
