El Atazar Dam is an

arch dam An arch dam is a concrete dam that is curved upstream in plan. The arch dam is designed so that the force of the water against it, known as hydrostatic pressure, presses against the arch, causing the arch to straighten slightly and strengthe ...

built near

Madrid Madrid ( , ) is the capital and most populous city of Spain. The city has almost 3.4 million inhabitants and a metropolitan area population of approximately 6.7 million. It is the second-largest city in the European Union (EU), and ...

Spain , image_flag = Bandera de España.svg , image_coat = Escudo de España (mazonado).svg , national_motto = '' Plus ultra'' (Latin)(English: "Further Beyond") , national_anthem = (English: "Royal March") , ...

on the

Lozoya River The Lozoya River () is a river flowing near the centre of Spain. It originates at a high altitude in the Sistema Central and cuts downward through steep rocks to flow into the Jarama River, a major tributary of the Tajo, the longest river on ...

, very close to where the Lozoya joins the

Jarama Jarama () is a river in central Spain. It flows north to south, and passes east of Madrid where the El Atazar Dam is built on a tributary, the Lozoya River. It flows into the river Tagus in Aranjuez. The Manzanares is a tributary of the Jaram ...

. The curved design of the dam is optimum for the narrow

gorge A canyon (from ; archaic British English spelling: ''cañon''), or gorge, is a deep cleft between escarpments or cliffs resulting from weathering and the erosive activity of a river over geologic time scales. Rivers have a natural tendency to cu ...

in which it was built to retain water in the

reservoir A reservoir (; from French ''réservoir'' ) 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. Reservoirs can be created in a number of ways, including contr ...

. Arch dams are thin and require less material to construct than other dam types. When the dam was built, the decision was made to use the dam to store and regulate water only and not to provide energy. Construction started on the dam in 1968 and finished in 1972.

Design

The dam is 134 m (440 ft) high and 52.3 m (171.6 ft) wide at the foundation. The reservoir capacity is 424,000,000 m³ (344,000 acre feet). It is a double

curvature In mathematics, curvature is any of several strongly related concepts in geometry. Intuitively, the curvature is the amount by which a curve deviates from being a straight line, or a surface deviates from being a plane. For curves, the can ...

concrete arch

buttress A buttress is an architectural structure built against or projecting from a wall which serves to support or reinforce the wall. Buttresses are fairly common on more ancient buildings, as a means of providing support to act against the lateral (s ...

design.

Problems

Monitoring of the dam revealed abnormal movement. Although dams normally move, the left side of the El Atazar Dam was moving more than the right because a support built on the dam's right made that side less flexible. In 1977 a crack was noticed in the dam. By 1979 the crack had grown to 46 m (150 ft) in length and was repaired. Inspection in 1983 revealed that the settling in the foundations and the movements of the dam had caused fracturing in the rock, resulting in significantly increasing the foundation's permeability. The crack has been treated and since then the problems have abated.

Power plant

The dam supports a hydroelectric power plant with a

nameplate capacity Nameplate capacity, also known as the rated capacity, nominal capacity, installed capacity, or maximum effect, is the intended full-load sustained output of a facility such as a power station,

of 9,56 MW. Its annual generation lies between 18,66 (2012) and 44,49 (1998) GWh. The power station contains 2

Francis turbine The Francis turbine is a type of water turbine. It is an inward-flow reaction turbine that combines radial and axial flow concepts. Francis turbines are the most common water turbine in use today, and can achieve over 95% efficiency. The proc ...

-generators with 4,78 MW (5,4 MVA) each. The turbine rotation is 500 rpm. The

hydraulic head Hydraulic head or piezometric head is a specific measurement of liquid pressure above a vertical datum., 410 pages. See pp. 43–44., 650 pages. See p. 22. It is usually measured as a liquid surface elevation, expressed in units of length, ...

is 56 m. Maximum flow per turbine is 8 m³/s.

Gallery

Image:Después del embalse del Atazar.jpg Image:El Atazar dam view01.jpg Image:El Atazar dam view06.jpg Image:El Atazar Aerial View.JPG

Notes

External links

How is the way to build a Dam ? Sociedad Española de Presas y Embalses
profile {{DEFAULTSORT:Atazar Dam Dams in Spain Hydroelectric power stations in Spain Arch dams Buildings and structures in the Community of Madrid Dams completed in 1972 Reservoirs in the Community of Madrid