Challawa Gorge Dam
Encyclopedia
The Challawa Gorge Dam is in Kano State
in the Northeast of Nigeria
, about 90 km southwest of Kano city. It is a major reservoir on the Challawa River, a tributary of the Kano River
, which is the main tributary of the Hadejia River
.
The dam was built by Julius Berger Nigeria in 1990 - 1992 using rock fill construction. It is 42 m high and 7.8 km in length.
The dam has a full storage capacity of 904,000,000 m3. The direct catchment area is 3857 km2.
The dam has disrupted the natural balance along the river. Upstream areas are now subject to flooding while downstream riverine wetlands and croplands have dried out.
A 2002 study noted that while the dam was intended to support irrigation projects, none had been started, although much farmland had been covered by the dam. The water was being used only to supply Kano
city. The Challawa dam and the nearby Tiga Dam
have also had adverse affects on the downstream Hadejia-Nguru wetlands
.
Several studies have shown that these dams have delivered negative economic value when their effect on downstream communities was taken into account.
Kano State
Kano State is a state located in North-Western Nigeria. Created on May 27, 1967 from part of the Northern Region, Kano state borders Katsina State to the north-west, Jigawa State to the north-east, Bauchi State to the south-east and Kaduna State to the south-west...
in the Northeast of Nigeria
Nigeria
Nigeria , officially the Federal Republic of Nigeria, is a federal constitutional republic comprising 36 states and its Federal Capital Territory, Abuja. The country is located in West Africa and shares land borders with the Republic of Benin in the west, Chad and Cameroon in the east, and Niger in...
, about 90 km southwest of Kano city. It is a major reservoir on the Challawa River, a tributary of the Kano River
Kano River
The is a 1st class river in Shizuoka Prefecture of cenral Japan. It is 46 km long and has a watershed of 853 km².The Kano River rises from Mount Amagi in central Izu Peninsula and follows a generally northern path into Suruga Bay at Numazu. The Izu Peninsula is characterized by heavy...
, which is the main tributary of the Hadejia River
Hadejia River
The Hadejia River is a river in northern Nigeria and is a tributary of the Yobe River .Among the cities and towns that lie on or near its banks are Hadejia and Nguru....
.
Construction
The Challawa Gorge reservoir project was started by the Water Resources and Engineering Construction Agency of the Kano State Government, and was later handed over to the Federal Government who funded the project. The dam is owned and operated by the Hadejia-Jama’are River Basin Development Authority, a Federal agency.The dam was built by Julius Berger Nigeria in 1990 - 1992 using rock fill construction. It is 42 m high and 7.8 km in length.
The dam has a full storage capacity of 904,000,000 m3. The direct catchment area is 3857 km2.
Hydro power potential
The dam was designed with the potential for hydro power generation in mind, and may have a capacity of 3MW on average - more in the rainy season and less in dry season. However, power would cost considerably more to deliver than current retail prices, and it is not clear how a project to install the generating equipment would be financed.Issues
The soil in the immediate catchments of the dam has not been stabilized, so the reservoir may be silting up. Silt is also being deposited in the Challawa River, affecting the intake structures of Kano City Water Supply.The dam has disrupted the natural balance along the river. Upstream areas are now subject to flooding while downstream riverine wetlands and croplands have dried out.
A 2002 study noted that while the dam was intended to support irrigation projects, none had been started, although much farmland had been covered by the dam. The water was being used only to supply Kano
Kano
Kano is a city in Nigeria and the capital of Kano State in Northern Nigeria. Its metropolitan population is the second largest in Nigeria after Lagos. The Kano Urban area covers 137 sq.km and comprises six Local Government Area - Kano Municipal, Fagge, Dala, Gwale, Tarauni and Nassarawa - with a...
city. The Challawa dam and the nearby Tiga Dam
Tiga Dam
The Tiga Dam is in Kano State in the Northeast of Nigeria, constructed in 1971-1974. It is a major reservoir on the Kano River, the main tributary of the Hadejia River. Water from the dam supplies the Kano River Irrigation Project as well as Kano City...
have also had adverse affects on the downstream Hadejia-Nguru wetlands
Hadejia-Nguru wetlands
thumb|right|300px|[[Yobe River]] catchment area showing location of the Hadejia-Nguru wetlandsThe Hadejia-Nguru wetlands in Yobe State in northern Nigeria, which include Nguru Lake, are ecologically and economically important...
.
Several studies have shown that these dams have delivered negative economic value when their effect on downstream communities was taken into account.