The Darbandikhan Dam ( ku, Bendava Derbendîxanê ,بەنداوی دەربەندیخان) is a multi-purpose

embankment dam 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 an ...

on the

Diyala River The Diyala River (Arabic: ; ku, Sîrwan; Farsi: , ) is a river and tributary of the Tigris. It is formed by the confluence of Sirwan river and Tanjaro river in Darbandikhan Dam in the Sulaymaniyah Governorate of Northern Iraq. It covers a to ...

in northern

Sulaymaniyah Governorate ar, محافظة السليمانية , other_name = , settlement_type = Governorate , image_skyline = , imagesize = , image_caption = Clockwise, from ...

Iraq Iraq,; ku, عێراق, translit=Êraq officially the Republic of Iraq, '; ku, کۆماری عێراق, translit=Komarî Êraq is a country in Western Asia. It is bordered by Turkey to Iraq–Turkey border, the north, Iran to Iran–Iraq ...

. It was constructed between 1956 and 1961. The purpose of the dam is

irrigation Irrigation (also referred to as watering) is the practice of applying controlled amounts of water to land to help grow crops, landscape plants, and lawns. Irrigation has been a key aspect of agriculture for over 5,000 years and has been devel ...

flood control Flood control methods are used to reduce or prevent the detrimental effects of flood waters."Flood Control", MSN Encarta, 2008 (see below: Further reading). Flood relief methods are used to reduce the effects of flood waters or high water level ...

hydroelectric Hydroelectricity, or hydroelectric power, is electricity generated from hydropower (water power). Hydropower supplies one sixth of the world's electricity, almost 4500 TWh in 2020, which is more than all other renewable sources combined an ...

power production and

recreation Recreation is an activity of leisure, leisure being discretionary time. The "need to do something for recreation" is an essential element of human biology and psychology. Recreational activities are often done for enjoyment, amusement, or plea ...

. Due to poor construction and neglect, the dam and its 249 MW power station have undergone several repairs over the years. A rehabilitation of the power station began in 2007 and was completed in 2013.

Background

After the Harza Engineering Company of USA designed the dam, construction began in 1956. The reservoir began to fill in November 1961 and the dam was complete that same year. After the reservoir filled, several problems occurred. In 1967, there was a major

slope failure Landslides, also known as landslips, are several forms of mass wasting that may include a wide range of ground movements, such as rockfalls, deep-seated slope failures, mudflows, and debris flows. Landslides occur in a variety of environme ...

about upstream of the dam. This and other slope failures are continually under repair. The bedrock beneath the dam has to be re-grouted and the crest of the dam settled too much, required it to be repaired. The

rip-rap Riprap (in North American English), also known as rip rap, rip-rap, shot rock, rock armour (in British English) or rubble, is human-placed rock or other material used to protect shoreline structures against scour and water, wave, or ice erosion ...

on the upstream face of the dam was also repaired in 1999 and 2000. Between 1983 and 1985 the dam's power station was replaced by German ( Polensky & Zöllner) and Japanese companies (

Mitsui is one of the largest ''keiretsu'' in Japan and one of the largest corporate groups in the world. The major companies of the group include Mitsui & Co. ( general trading company), Sumitomo Mitsui Banking Corporation, Nippon Paper Industries ...

). The original 2 × 800 kW generators were replaced with the current power plant's 83 MW generators. The generators were commissioned in 1990 after the political situation in the country calmed. However, two of the generators were not commissioned correctly and the turbines suffered from severe

cavitation Cavitation is a phenomenon in which the static pressure of a liquid reduces to below the liquid's vapour pressure, leading to the formation of small vapor-filled cavities in the liquid. When subjected to higher pressure, these cavities, ca ...

. New spillway gates were installed between 1989 and 1990 after they were removed in 1988 because of the

Iran–Iraq War The Iran–Iraq War was an armed conflict between Iran and Iraq that lasted from September 1980 to August 1988. It began with the Iraqi invasion of Iran and lasted for almost eight years, until the acceptance of United Nations Security Counci ...

. During the war, the spillway and substation were damaged from bombing. The power station was damaged from bombing in 1990 as well. In 2007, the

World Bank The World Bank is an international financial institution that provides loans and grants to the governments of low- and middle-income countries for the purpose of pursuing capital projects. The World Bank is the collective name for the Inte ...

began a US$35.36 million project to repair the Darbandikhan and

Dokan Dam The Dukan Dam (Sorani Kurdish: بەنداوی دووکان Arabic: سد دوكان) is a multi-purpose concrete arch dam in As Sulaymaniyah Governorate, Kurdistan Region of Iraq. It impounds the Little Zab, thereby creating Lake Dukan. The Dukan Da ...

s. Repairs to the Darbandikhan Dam cost $18.85 million and were completed in 2013 resulting in 100 percent power availability.

Design and operation

The dam is located within a gorge on a foundation of sedimentary rocks. It is a rock-fill embankment type with a central clay core. The dam is tall and long ( if the spillway section is included). Its crest is wide and at an elevation of . The structural volume of the dam including rock, clay and filters is . The dam collects water from a

catchment area In human geography, a catchment area is the area from which a location, such as a city, service or institution, attracts a population that uses its services and economic opportunities. Catchment areas may be defined based on from where people are ...

that covers . Its reservoir, by design, has a storage capacity of . Of that capacity, is active (or useful) storage while is dead storage. At a normal elevation of , the reservoir covers an area of . To protect the dam from flooding, it is equipped with a controlled chute

spillway A spillway is a structure used to provide the controlled release of water downstream from a dam or levee, typically into the riverbed of the dammed river itself. In the United Kingdom, they may be known as overflow channels. Spillways ensure th ...

on its right bank. It is controlled by three x 15 m

tainter gate The Tainter gate is a type of radial arm floodgate used in dams and canal locks to control water flow. It is named for Wisconsin structural engineer Jeremiah Burnham Tainter. A side view of a Tainter gate resembles a slice of pie with the ...

s. At the terminus of each chute there is a ski-jump to help dissipate energy. The maximum discharge capacity of the spillway is . The dam's power plant is located at its toe and contains 3 x 83 MW

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. They are each afforded a rated

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, ...

of and can each discharge . Above the tail-race for each turbine is an irrigation outlet. Each of the three outlets can discharge up to downstream.

References

External links

* {{Diyala River dams Dams in Iraq Dams on the Diyala (Sirwan) River Hydroelectric power stations in Iraq Rock-filled dams Sulaymaniyah Governorate Geography of Iraqi Kurdistan Dams completed in 1961 1961 establishments in Iraq Energy infrastructure completed in 1990

Background

Design and operation

See also

References

External links