Aldeadávila Dam
Encyclopedia
Aldeadávila Dam is a concrete
arch-gravity dam
on the Douro
River (also known as the Duero River) on the border between Spain and Portugal. The Douro River forms the international boundary between Portugal and Spain. The nearest Spanish town is Aldeadávila de la Ribera
in the Province of Salamanca, about 11.3 kilometres (7 mi) to the east. The nearest Portuguese town is Fornos
in Bragança District, about 8 kilometres (5 mi) to the southwest. The Portuguese side of the river around the dam site lies within the International Douro Natural Park
.
The dam is 140 metres (459.3 ft) high and its cost was estimated in 1962 at US$60,000,000 (about $443.5 million in 2010 inflated-adjusted dollars). It was one of a series of very high dams built in Europe in the two decades after World War II which incorporated a downstream face inclined toward the upstream flow. This simplified the dam's design and construction (although it required more concrete to build), and more readily incorporated the spillway
s into the dam face. Indeed, the dam's face is nearly vertical. Design work on the dam began in 1956, and construction completed in 1963. The structure was built by the Iberdrola Ingeniería y Construcción construction firm. Pedro Martínez Artola was the design engineer. The dam was built on high-quality granite
rock. During construction, grout
ing was used to fill cracks in the rock which ran parallel to the dam's foundation, and on the Portuguese bank where two fractures in the rock occurred. The underground power station and tunnels were excavated using a mining procedure known as large-chamber stoping
, and the dam's use of this technique is considered a textbook example. The turbine and generator hall and the transformer hall were both cut from solid granite as well. The turbine and generator room is 140 metres (459.3 ft) long, 18 metres (59.1 ft) wide, and 40 metres (131.2 ft) deep. The total volume of excavated material for all halls, rooms, and abutments was 600175 cubic metres (784,999.3 cu yd).
The structure has eight overflow gates
which channel water into four spillways. The spillways incorporate side piers on the upstream face to more correctly channel water over the dam so that each spillway discharges the same amount of water. The spillways release their water slightly above the actual bed of the river, creating a waterfall effect when they are fully open. A spillway tunnel carved from granite in the right bank of the river augments the spillways and provides for additional overflow. The total spillway capacity is half that of Grand Coulee Dam
. The Export-Import Bank of the United States
provided $8.9 million (about $67.2 million in 2010 inflation-adjusted dollars) in credits in 1958 to Iberduero to enable it to purchase six 120 Megawatt (MW) turbines and other electrical equipment for the power generating station, all of which was supplied by American firms.
The dam won Spain an international reputation as a builder of very large dams. The dam's eye-catching, "ski jump" style spillways are its most noted feature, and have been called "outstanding" by leading dam engineers.
The canyon through which the Douro River flows is exceptionally deep and narrow, leaving behind a reservoir that has a relatively small surface area for its immense size. In some ways, this limits use of the reservoir for recreational activities. However, the Aldeadávila Dam reservoir is a popular one for boating
.
capability. The dam's power plant contains 2 x 211 MW pumped-storage generators than can generate power in the normal way by allowing water to flow through its turbines. However, during periods when the demand for electricity is low (such as evenings, weekends, or during seasonal fluctuations), the dam can use its excess power generating capacity to pump water back into the reservoir—enhancing reservoir capacity and storing water for periods when the demand for electricity is high. At the time it was constructed, the Aldeadávila Dam had the largest pumping station in Europe.
The Aldeadávila Dam has two diversion tunnels, each 1400 metres (4,593.2 ft) in length. Each tunnel has a 53 metres (173.9 ft) high surge tank. The dam also contains more than 12 kilometres (7.5 mi) of tunnels which divert water to the electrical generation turbines. There are six penstock
tunnels, each about 5 metres (16.4 ft) in diameter. The design of the penstocks and auxiliary spillways using these tunnels has proved to be an issue, however. Cavitation problems have damaged these tunnels in the past. Until the Alcantara Dam
was built in 1969, the Aldeadávila Dam was the largest hydroelectric power
plant in Europe. As of 2010, it remains the largest in Spain. The dam's hydroelectric power station originally housed six 170000 hp Francis turbine
s which generated 718 MW, about half that of Hoover Dam
. In 1987, the Aldeadávila II power station extension was completed, boosting generating capacity by 400 MW.
film Doctor Zhivago were filmed at the Aldeadávila Dam. The dam's famous spillways were opened for the filming, and are shown in the motion picture open at full force. Another scene depicts workers walking into one of the dam's enormous tunnels. The final scenes of Antonio Mercero
's 1972 film, La cabina
(The Telephone Box) were also filmed inside the dam.
Concrete
Concrete is a composite construction material, composed of cement and other cementitious materials such as fly ash and slag cement, aggregate , water and chemical admixtures.The word concrete comes from the Latin word...
arch-gravity dam
Arch-gravity dam
An arch-gravity dam, curved-gravity dam or arched dam is a dam with the characteristics of both an arch dam and a gravity dam. It is a dam that curves upstream in a narrowing curve that directs most of the water against the canyon rock walls, providing the force to compress the dam...
on the Douro
Douro
The Douro or Duero is one of the major rivers of the Iberian Peninsula, flowing from its source near Duruelo de la Sierra in Soria Province across northern-central Spain and Portugal to its outlet at Porto...
River (also known as the Duero River) on the border between Spain and Portugal. The Douro River forms the international boundary between Portugal and Spain. The nearest Spanish town is Aldeadávila de la Ribera
Aldeadávila de la Ribera
Aldeadavila de la Ribera is a village and municipality in the north-west of the province of Salamanca, western Spain, part of the autonomous community of Castile-Leon.-External links:...
in the Province of Salamanca, about 11.3 kilometres (7 mi) to the east. The nearest Portuguese town is Fornos
Fornos (Freixo de Espada à Cinta)
Fornos is a civil parish in the municipality of Freixo de Espada à Cinta, located 17 kilometres south of the municipal seat, in the northeast of Portugal...
in Bragança District, about 8 kilometres (5 mi) to the southwest. The Portuguese side of the river around the dam site lies within the International Douro Natural Park
International Douro Natural Park
The International Douro Natural Park is one of the thirteen natural parks of Portugal. It is located in the municipalities of Miranda do Douro, Mogadouro, Freixo de Espada à Cinta and Figueira de Castelo Rodrigo, spanning through a wide area along the Douro River as it makes the border between...
.
About the dam
In 1864, Portugal and Spain signed the "Treaty of Limits" (ratified in 1866), which established the present international boundaries of the two nations. A treaty on transboundary rivers clarifying issues regarding the use of such rivers was signed and affirmed in 1912. A treaty regulating the development of hydroelectric facilities on the Douro River was signed in 1927. The Aldeadávila Dam was built by Spain pursuant to these treaties, and was the final dam to be built by Spain on the section of river alloted to that country.The dam is 140 metres (459.3 ft) high and its cost was estimated in 1962 at US$60,000,000 (about $443.5 million in 2010 inflated-adjusted dollars). It was one of a series of very high dams built in Europe in the two decades after World War II which incorporated a downstream face inclined toward the upstream flow. This simplified the dam's design and construction (although it required more concrete to build), and more readily incorporated the spillway
Spillway
A spillway is a structure used to provide the controlled release of flows from a dam or levee into a downstream area, typically being the river that was dammed. In the UK they may be known as overflow channels. Spillways release floods so that the water does not overtop and damage or even destroy...
s into the dam face. Indeed, the dam's face is nearly vertical. Design work on the dam began in 1956, and construction completed in 1963. The structure was built by the Iberdrola Ingeniería y Construcción construction firm. Pedro Martínez Artola was the design engineer. The dam was built on high-quality granite
Granite
Granite is a common and widely occurring type of intrusive, felsic, igneous rock. Granite usually has a medium- to coarse-grained texture. Occasionally some individual crystals are larger than the groundmass, in which case the texture is known as porphyritic. A granitic rock with a porphyritic...
rock. During construction, grout
Grout
Grout is a construction material used to embed rebars in masonry walls, connect sections of pre-cast concrete, fill voids, and seal joints . Grout is generally composed of a mixture of water, cement, sand, often color tint, and sometimes fine gravel...
ing was used to fill cracks in the rock which ran parallel to the dam's foundation, and on the Portuguese bank where two fractures in the rock occurred. The underground power station and tunnels were excavated using a mining procedure known as large-chamber stoping
Stoping (mining method)
Stoping is the removal of the wanted ore from an underground mine leaving behind an open space known as a stope. Stoping is used when the country rock is sufficiently strong not to cave into the stope, although in most cases artificial support is also provided...
, and the dam's use of this technique is considered a textbook example. The turbine and generator hall and the transformer hall were both cut from solid granite as well. The turbine and generator room is 140 metres (459.3 ft) long, 18 metres (59.1 ft) wide, and 40 metres (131.2 ft) deep. The total volume of excavated material for all halls, rooms, and abutments was 600175 cubic metres (784,999.3 cu yd).
The structure has eight overflow gates
Floodgate
Floodgates are adjustable gates used to control water flow in flood barriers, reservoir, river, stream, or levee systems. They may be designed to set spillway crest heights in dams, to adjust flow rates in sluices and canals, or they may be designed to stop water flow entirely as part of a levee or...
which channel water into four spillways. The spillways incorporate side piers on the upstream face to more correctly channel water over the dam so that each spillway discharges the same amount of water. The spillways release their water slightly above the actual bed of the river, creating a waterfall effect when they are fully open. A spillway tunnel carved from granite in the right bank of the river augments the spillways and provides for additional overflow. The total spillway capacity is half that of Grand Coulee Dam
Grand Coulee Dam
Grand Coulee Dam is a gravity dam on the Columbia River in the U.S. state of Washington built to produce hydroelectric power and provide irrigation. It was constructed between 1933 and 1942, originally with two power plants. A third power station was completed in 1974 to increase its energy...
. The Export-Import Bank of the United States
Export-Import Bank of the United States
The Export-Import Bank of the United States is the official export credit agency of the United States federal government. It was established in 1934 by an executive order, and made an independent agency in the Executive branch by Congress in 1945, for the purposes of financing and insuring...
provided $8.9 million (about $67.2 million in 2010 inflation-adjusted dollars) in credits in 1958 to Iberduero to enable it to purchase six 120 Megawatt (MW) turbines and other electrical equipment for the power generating station, all of which was supplied by American firms.
The dam won Spain an international reputation as a builder of very large dams. The dam's eye-catching, "ski jump" style spillways are its most noted feature, and have been called "outstanding" by leading dam engineers.
The canyon through which the Douro River flows is exceptionally deep and narrow, leaving behind a reservoir that has a relatively small surface area for its immense size. In some ways, this limits use of the reservoir for recreational activities. However, the Aldeadávila Dam reservoir is a popular one for boating
Boating
Boating is the leisurely activity of travelling by boat, or the recreational use of a boat whether powerboats, sailboats, or man-powered vessels , focused on the travel itself, as well as sports activities, such as fishing or water skiing...
.
Power plant
The Aldeadávila Dam has a 422 MW pumped-storagePumped-storage hydroelectricity
Pumped-storage hydroelectricity is a type of hydroelectric power generation used by some power plants for load balancing. The method stores energy in the form of water, pumped from a lower elevation reservoir to a higher elevation. Low-cost off-peak electric power is used to run the pumps...
capability. The dam's power plant contains 2 x 211 MW pumped-storage generators than can generate power in the normal way by allowing water to flow through its turbines. However, during periods when the demand for electricity is low (such as evenings, weekends, or during seasonal fluctuations), the dam can use its excess power generating capacity to pump water back into the reservoir—enhancing reservoir capacity and storing water for periods when the demand for electricity is high. At the time it was constructed, the Aldeadávila Dam had the largest pumping station in Europe.
The Aldeadávila Dam has two diversion tunnels, each 1400 metres (4,593.2 ft) in length. Each tunnel has a 53 metres (173.9 ft) high surge tank. The dam also contains more than 12 kilometres (7.5 mi) of tunnels which divert water to the electrical generation turbines. There are six penstock
Penstock
A penstock is a sluice or gate or intake structure that controls water flow, or an enclosed pipe that delivers water to hydraulic turbines and sewerage systems. It is a term that has been inherited from the technology of wooden watermills....
tunnels, each about 5 metres (16.4 ft) in diameter. The design of the penstocks and auxiliary spillways using these tunnels has proved to be an issue, however. Cavitation problems have damaged these tunnels in the past. Until the Alcantara Dam
Alcantara Dam
The Alcantara Dam, also known as the Jose María de Oriol Dam, in Spain, regulates much of the flow of the Tagus River, the longest of the Iberian Peninsula, just before the river enters Portugal. It was built in 1969 and is the second largest reservoir in Europe...
was built in 1969, the Aldeadávila Dam was the largest hydroelectric power
Hydroelectricity
Hydroelectricity is the term referring to electricity generated by hydropower; the production of electrical power through the use of the gravitational force of falling or flowing water. It is the most widely used form of renewable energy...
plant in Europe. As of 2010, it remains the largest in Spain. The dam's hydroelectric power station originally housed six 170000 hp Francis turbine
Francis turbine
The Francis turbine is a type of water turbine that was developed by James B. Francis in Lowell, Massachusetts. It is an inward-flow reaction turbine that combines radial and axial flow concepts....
s which generated 718 MW, about half that of Hoover Dam
Hoover Dam
Hoover Dam, once known as Boulder Dam, is a concrete arch-gravity dam in the Black Canyon of the Colorado River, on the border between the US states of Arizona and Nevada. It was constructed between 1931 and 1936 during the Great Depression and was dedicated on September 30, 1935, by President...
. In 1987, the Aldeadávila II power station extension was completed, boosting generating capacity by 400 MW.
In popular culture
A 30-minute documentary about the dam, La presa de Aldeadávila, was produced by Iberduero (the power company that built the dam) in 1963. Several scenes in the 1965 David LeanDavid Lean
Sir David Lean CBE was an English film director, producer, screenwriter, and editor best remembered for big-screen epics such as The Bridge on the River Kwai , Lawrence of Arabia ,...
film Doctor Zhivago were filmed at the Aldeadávila Dam. The dam's famous spillways were opened for the filming, and are shown in the motion picture open at full force. Another scene depicts workers walking into one of the dam's enormous tunnels. The final scenes of Antonio Mercero
Antonio Mercero
Antonio Mercero is a Spanish director of the series Verano azul and later Farmacia de guardia. He is best known as the director of a 1972 surrealist short horror film titled La cabina, that won an Emmy Award...
's 1972 film, La cabina
La cabina
La cabina is an Emmy award-winning, 1972 film directed by Spanish director Antonio Mercero, and written by him and José Luis Garci...
(The Telephone Box) were also filmed inside the dam.
External links
- Iberdrola - Web site of the company which owns the dam
- Búrdalo, Soledad. "Geometría tectónica." La Revista del Ministerio de Fomento. Abril 2007. - Article from The Magazine of the Ministry of Public Works and the Economy about the construction of the dam.
- Artola, Pedro Martínez. "El Salto de Aldeadávila." Revista de Obras Públicas. Diciembre 1962. - Article by dam engineer Pedro Martínez Artola in the Journal of Public Works on the construction of the dam.
- Olaguibel, L. "La Construccion de la Presa de Aldeadávila." Revista de Obras Públicas. Abril 1964. - Article in the Journal of Public Works on the construction of the dam.