Kainji Dam
Map of Nigeria showing the location of Kainji Dam.
Location	Kainji, Niger, Nigeria
Coordinates	09°51′45″N 04°36′48″E / 9.86250°N 4.61333°E / 9.86250; 4.61333
Construction began	1964
Opening date	1968
Construction cost	US$209 million
Owner(s)	Federal Government of Nigeria
Operator(s)	Mainstream Energy
Dam and spillways
Impounds	Niger River
Height	65 m (213 ft)
Length	550 m (1,804 ft)
Reservoir
Creates	Kainji Lake
Power Station
Commission date	1968
Turbines	8
Installed capacity	760 megawatts (1,020,000 hp) 960 megawatts (1,290,000 hp) (max)

Kainji Dam is a dam across the Niger River in Niger State of Central Nigeria.^[1] Construction of the dam was carried out by Impregilo (a consortium of Italian Civil Engineering Contractors) to designs by Joint Consultants, Balfour Beatty and Nedeco, and began in 1964 to be completed in 1968.^[2] The total cost was estimated at US$209 million (equivalent to about US$1.4 billion in 2022 dollars^[3]), with one-quarter of this amount used to resettle people displaced by the construction of the dam and its reservoir, Kainji Lake.^[4][5]

Dimensions

Kainji Dam extends for about 10 kilometres (6.2 mi), including its saddle dam, which closes off a tributary valley. The primary section across the outflow to the Niger is 550 metres (1,800 ft). Most of the structure is made from earth, but the centre section, housing the hydroelectric turbines, was built from concrete. This section is 65 metres (213 ft) high. Kanji Dam is one of the longest dams in the world.^[6]

Power station

The dam was designed to have a generating capacity of 960 megawatts (1,290,000 hp); however, only 8 of its 12 turbines have been installed, reducing the capacity to 760 megawatts (1,020,000 hp).^[7] The dam generates electricity for all the large cities in Nigeria.^[8] Some of the electricity is sold to the neighbouring country of Niger. In addition, occasional droughts have made the Niger's water flow unpredictable, diminishing the dam's electrical output.^[9]

• 
  Flow of water through four openings in the Kainji Dam, 1970–1973.
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  Overview from the dam of the island in the Niger River with electricity File:pylons, 1970–1973.
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  Zebus crossing the dam, 1970–1973.
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  A shepherd boy at the dam, 1970–1973.
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  Man above the foaming water, 1970–1973.

Lock

The dam has a single-lock chamber capable of lifting barges 49 metres (161 ft).

Discharge flooding

In October 1998, in response to upstream flooding, a torrent of water was released from the dam, bursting the river banks. Downstream from the dam 60 villages were flooded. Domestic animals drowned and dikes as well as several farms were washed away. Dam officials were criticized for waiting too long before starting, then dumping too much water.^[10]

Lake Kainji

Kainji Lake measures about 135 kilometres (84 mi) long and about 30 kilometres (19 mi) at its widest point, and supports irrigation and a local fishing industry.^[11] In 1999, uncoordinated opening of floodgates led to local flooding of about 60 villages.^[12]