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 earliest known dam is the Jawa Dam in Jordan, dating to 3,000 BC.
The United States Army Corps of Engineers (USACE) is an engineer formation of the United States Army that has three primary mission areas: Engineer Regiment, military construction, and civil works. The day-to-day activities of the three mission areas are administered by a lieutenant general known as the commanding general/chief of engineers. The chief of engineers commands the Engineer Regiment, comprising combat engineer, rescue, construction, dive, and other specialty units, and answers directly to the Chief of Staff of the Army. Combat engineers, sometimes called sappers, form an integral part of the Army's combined arms team and are found in all Army service components: Regular Army, National Guard, and Army Reserve. Their duties are to breach obstacles; construct fighting positions, fixed/floating bridges, and obstacles and defensive positions; place and detonate explosives; conduct route clearance operations; emplace and detect landmines; and fight as provisional infantry when required. For the military construction mission, the commanding general is directed and supervised by the Assistant Secretary of the Army for installations, environment, and energy, whom the President appoints and the Senate confirms. Military construction relates to construction on military bases and worldwide installations.
Saint Anthony Falls, or the Falls of Saint Anthony located at the northeastern edge of downtown Minneapolis, Minnesota, is the only natural major waterfall on the Mississippi River. Throughout the mid-to-late 1800’s, various dams were built atop the east and west faces of the falls to support the milling industry that spurred the growth of the city of Minneapolis. In 1880, the central face of the falls was reinforced with a sloping timber apron to stop the upstream erosion of the falls. In the 1950s, the apron was rebuilt with concrete, which makes up the most visible portion of the falls today. A series of locks were constructed in the 1950s and 1960s to extend navigation to points upstream.
Rainy Lake is a freshwater lake with a surface area of 360 square miles (932 km2) that straddles the border between the United States and Canada. The Rainy River issues from the west side of the lake and is harnessed to make hydroelectricity for US and Canadian locations. International Falls, Minnesota and the much smaller city of Ranier, Minnesota are situated opposite Fort Frances, Ontario, on either side of the Rainy River. Rainy Lake and Rainy River establish part of the boundary between the US state of Minnesota and the Canadian province of Ontario.
Pine Flat Dam is a concrete gravity dam on the Kings River in the Central Valley of Fresno County, California United States. Situated about 28 miles (45 km) east of Fresno, the dam is 440 feet (130 m) high and impounds Pine Flat Lake, one of the largest reservoirs in California, in the foothills of the Sierra Nevada just outside the boundary of Kings Canyon National Park. The dam's primary purpose is flood control, with irrigation, hydroelectric power generation and recreation secondary in importance.
Gavins Point Dam is a 1.9 mi (3 km) long embankment rolled-earth and chalk-fill dam which spans the Missouri River and impounds Lewis and Clark Lake. The dam joins Cedar County, Nebraska with Yankton County, South Dakota a distance of 811.1 river miles (1,305 km) upstream of St. Louis, Missouri, where the river joins the Mississippi River. The dam and hydroelectric power plant were constructed as the Gavins Point Project from 1952 to 1957 by the United States Army Corps of Engineers as part of the Pick-Sloan Plan. The dam is located approximately 4 miles (6.4 km) west or upstream of Yankton, South Dakota.
Ford Dam, officially known as Lock and Dam No. 1, is on the Upper Mississippi River and is located between Minneapolis and Saint Paul, Minnesota just north of the confluence of the Mississippi with the Minnesota River at Mississippi River mile 847.9, in Minneapolis. The powerhouse portion was previously owned by the Ford Motor Company, which operated a hydroelectric power station to feed electricity to its Twin Cities Assembly Plant on the east side of the river. It was sold to Brookfield Power Co. in April 2008. The dual-lock facility and dam was built and is operated by the St. Paul district of the U.S. Army Corps of Engineers' Mississippi Valley Division.
Lock and Dam No. 7 is a lock and dam located on the Upper Mississippi River at river mile 702.5 near the cities of La Crescent, Minnesota and Onalaska, Wisconsin. It forms pool 7 and Lake Onalaska. The facility was constructed in the mid-1930s and placed in operation on April, 1937. It underwent major rehabilitation from 1989 through 2002. The lock and dam are owned and operated by the St. Paul District of the United States Army Corps of Engineers-Mississippi Valley Division.
Terminus Dam is a dam on the Kaweah River in Tulare County, California in the United States, located near Three Rivers about 15 mi (24 km) from the western boundary of Sequoia National Park and 20 mi (32 km) east of Visalia. The dam forms Lake Kaweah for flood control and irrigation water supply. Completed by the U.S. Army Corps of Engineers (USACE) in 1962, Terminus is an earthfill dam 255 ft (78 m) high and 2,375 ft (724 m) long. The reservoir has a maximum capacity of 185,600 acre⋅ft (0.2289 km3) of water, although it usually sits at much lower levels.
The Winnibigoshish Lake Dam is a dam at the outlet of Lake Winnibigoshish into the Mississippi River in Minnesota, United States. The dam crosses the county line between Cass County and Itasca County, and lies within the Leech Lake Indian Reservation. The first dam on the site was built by the United States Army Corps of Engineers from 1881 to 1884 to regulate the flow of water on the Upper Mississippi River. A constant flow was desired by loggers, fur traders, and millers downstream at St. Anthony Falls. The current structure was built in 1899. Lake Winnibigoshish is Minnesota's fifth largest lake, at 67,000 acres (270 km2).
J. Strom Thurmond Dam, also known in Georgia as Clarks Hill Dam, is a concrete-gravity and embankment dam located 22 miles (35 km) north of Augusta, Georgia on the Savannah River at the border of South Carolina and Georgia, creating Lake Strom Thurmond. U.S. Route 221 cross it. The dam was built by the U.S. Army Corps of Engineers between 1946 and 1954 for the purposes of flood control, hydroelectricity and downstream navigation. The concrete structure of the dam spans 1,096 feet (334 m) and rises 204 feet (62 m) above the riverbed, housing a power plant with an installed 380 MW capacity. The Dam has prevented over $185,000 in estimated flood damage annually and also provides recreation, water quality, water supply, along with fish and wildlife management.
Abiquiu Dam is a dam on the Rio Chama, located about 60 miles (97 km) northwest of Santa Fe in Rio Arriba County, New Mexico. Built and operated by the U.S. Army Corps of Engineers (USACE), the dam is an earth embankment structure 354 feet (108 m) high and 1,800 feet (550 m) long, containing 11.8 million cubic yards of fill. The dam forms Abiquiu Lake, one of the largest lakes in New Mexico with a full storage capacity of 1,369,000 acre-feet (1,689,000 dam3) and 5,200 acres (2,100 ha) of water. To date, the reservoir has never filled to capacity, with a record high of 402,258 acre-feet (496,178 dam3), 29.4% of full pool, on June 22, 1987. The dam's primary purpose is flood control, in addition to irrigation and municipal water storage, and hydroelectric generation.
Pokegama Lake Dam is a dam in Cohasset, Itasca County, Minnesota, northwest of the city of Grand Rapids.
Orwell Dam is a dam in Otter Tail County, Minnesota, about six miles southwest of Fergus Falls.
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.
Dayton Hollow Dam is a hydroelectric gravity dam on the Otter Tail River in Otter Tail County, Minnesota in the United States. It is located 5 miles southwest of the city of Fergus Falls. Completed in 1909, it is the first power plant built by the Otter Tail Power Company and is one of five dams on the river. Together, they produce about 3.5 megawatts of power.
Thomson Dam, also known as the Thomson Hydro Station or Thomson Water Project, is an embankment and concrete gravity dam on the Saint Louis River near the town of Thomson in northeastern Minnesota, United States. It consists of a 1600-foot long primary structure and multiple supplementary dams which, together with precambrian rock outcrops known as the Thomson formation, impound the river to create Thomson Reservoir.
The Klamath river begins below Upper Klamath Lake in Southern Oregon and flows about 300 miles through Northern California until draining into the Pacific ocean. Upper Klamath Lake is the largest freshwater lake in Oregon and was established by the late Pliocene period. The lake fills a graben that is thousands of meters deep. The Klamath Basin lies on the edge of the Basin and Range province and is adjacent to the High Cascades of Southern Oregon.
