Kihansi Dam
Encyclopedia
Kihansi Dam is a hydroelectric dam located on the Kihansi River at the end of the Kihansi Gorge before the convergence with the Ulanga River
in Tanzania
approximately 450 km southwest of the capital Dar Es Salaam
.
gravity dam owned by the Tanzania Electric Supply Company Limited
. Its construction began in July 1995 and was opened by President Benjamin W. Mkapa on 10 July 2000. It cost $36 million. Its installed capacity is 180 MW, and it helps provide aproximently 13% of the total electrical power in Tanzania.
. The dam reduced the amount of silt and water coming down from the waterfall into the gorge by 90 percent. This led to the spray toad's microhabitat being compromised, as it reduced the amount of water spray, which the toads were directly reliant on for oxygen. This also meant that the toad may have been more susceptible to a chytrid fungus, which was believed to have been transported to the area by conservationists' boots. This chytridiomycosis
, which in 2003 was confirmed to be in dead animals of the species, was possibly responsible for the sudden population crash after the world's largest sprinkler system was installed in that area in August 2003. This system was installed to try and conserve the toad species from becoming extinct in the wild, but did not succeed.
Ulanga River
The Ulanga River, also known as the Kilombero River, is a river that starts in the southwest of Tanzania on the eastern slope of the East African Rift that flows northeast into the Rufiji River then to the Indian Ocean.-Geology:...
in Tanzania
Tanzania
The United Republic of Tanzania is a country in East Africa bordered by Kenya and Uganda to the north, Rwanda, Burundi, and the Democratic Republic of the Congo to the west, and Zambia, Malawi, and Mozambique to the south. The country's eastern borders lie on the Indian Ocean.Tanzania is a state...
approximately 450 km southwest of the capital Dar Es Salaam
Dar es Salaam
Dar es Salaam , formerly Mzizima, is the largest city in Tanzania. It is also the country's richest city and a regionally important economic centre. Dar es Salaam is actually an administrative province within Tanzania, and consists of three local government areas or administrative districts: ...
.
Kihansi Dam
The Kihansi Dam is a concreteConcrete
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...
gravity dam owned by the Tanzania Electric Supply Company Limited
Tanesco
Tanzania Electric Supply Company Limited is a Tanzanian parastatal organisation established in 1964. It is wholly owned by the government of Tanzania...
. Its construction began in July 1995 and was opened by President Benjamin W. Mkapa on 10 July 2000. It cost $36 million. Its installed capacity is 180 MW, and it helps provide aproximently 13% of the total electrical power in Tanzania.
Environmental Impact
The Kihansi Dam destroyed an 800m-high waterfall, affected over 20,000 villagers, and was directly responsible for the extinction in the wild of the Kihansi Spray ToadKihansi Spray Toad
The Kihansi spray toad, Nectophrynoides asperginis, is a dwarf toad, with adults reaching no more than three quarters of an inch long. It was discovered in 1996. It was found only in the spray zone around the Kihansi and Mhalala waterfalls in the southern Udzungwa Mountains in Tanzania...
. The dam reduced the amount of silt and water coming down from the waterfall into the gorge by 90 percent. This led to the spray toad's microhabitat being compromised, as it reduced the amount of water spray, which the toads were directly reliant on for oxygen. This also meant that the toad may have been more susceptible to a chytrid fungus, which was believed to have been transported to the area by conservationists' boots. This chytridiomycosis
Chytridiomycosis
Chytridiomycosis is an infectious disease of amphibians, caused by the chytrid Batrachochytrium dendrobatidis, a non-hyphal zoosporic fungus. Chytridiomycosis has been linked to dramatic population declines or even extinctions of amphibian species in western North America, Central America, South...
, which in 2003 was confirmed to be in dead animals of the species, was possibly responsible for the sudden population crash after the world's largest sprinkler system was installed in that area in August 2003. This system was installed to try and conserve the toad species from becoming extinct in the wild, but did not succeed.