The Great Ruaha River is a

river A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases, a river flows into the ground and becomes dry at the end of its course without reaching another body of w ...

in south-central

Tanzania Tanzania (; ), officially the United Republic of Tanzania ( sw, Jamhuri ya Muungano wa Tanzania), is a country in East Africa within the African Great Lakes region. It borders Uganda to the north; Kenya to the northeast; Comoro Islands ...

that flows through the Usangu wetlands and the

Ruaha National Park Ruaha National Park is a national park in Tanzania. The addition of the Usangu Game Reserve and other important wetlands to the park in 2008 increased its size to about . The park is about west of Iringa. The park is a part of the Rungwa-Kizigo ...

east into the Rufiji River. It traverses and marks the borders between

Iringa Region Iringa Region (''Mkoa wa Iringa'' in Swahili) is one of Tanzania's 31 administrative regions. The region covers an area of . The region is comparable in size to the combined land area of the nation state of Guinea Bissau. Iringa Region is borde ...

Dodoma Region Dodoma Region (''Mkoa wa Dodoma'' in Swahili) is one of Tanzania's 31 administrative regions. The regional capital is the city of Dodoma. The region is located in central Tanzania, it is bordered by Singida Region to the west; Manyara Region ...

and

Morogoro Region Morogoro Region (''Mkoa wa Morogoro'' in Swahili) is one of Tanzania's 31 administrative regions. The region covers an area of . The region is comparable in size to the combined land area of the nation state of Ireland. Morogoro Region is border ...

. The Great Ruaha river has a basin catchment area of . The population of the basin is mainly sustained by

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 ...

and water-related livelihoods such as fishing and livestock keeping.

Size

Great Ruaha is about long, its tributary basin has a catchment area of and the mean annual discharge is per second. The Great Ruaha River supplies 22 percent of the total flow of the Rufiji catchment system. Thirty-eight species of fish have been identified in the Great Ruaha River. The river's headwaters are in the

Kipengere Range The Kipengere Range, also known as the Livingstone Mountains, lies entirely in Njombe Region in southwest Tanzania at the northern end of Lake Nyasa. Near Lake Nyasa they are known as the Kinga Mountains. It is a plateau-like ridge of mountains r ...

In west

Njombe Region Njombe Region (''Mkoa wa Njombe'' in Swahili) is one of Tanzania's 31 administrative regions. The region covers a land area of . The region is comparable in size to the combined land area of the nation state of El Salvador. Njombe Region is bor ...

. From there the Great Ruaha River descends to the Usangu plains, an important region for irrigated agriculture and livestock in Tanzania. The river eventually reaches the

Mtera Dam Mtera Dam is a hydroelectric dam in Tanzania. The dam is located midway between Iringa and Dodoma on the border between the Iringa Region and the Dodoma Region. The travel time from Dodoma is about two hours on a tarmac road. Overview Mtera Dam ...

and then flows south to the

Kidatu Dam Kidatu Dam, also Kidadu Hydroelectric Power Station, is a hydroelectric dam in Tanzania. Location The power station is located across the Great Ruaha River, in the village of Kilosa, in Morogoro Region, approximately , by road, southwest of D ...

. These two generate about 50 percent of Tanzania's electricity. The river continues southwards and flows across the Selous Game Reserve before reaching the Rufiji River. The major rivers contributing to the Great Ruaha River are Lukosi, Yovi, Kitete, Sanje, Little Ruaha, Kisigo, Mbarali, Kimani, and Chimala whereas the small ones include Umrobo, Mkoji, Lunwa, Mlomboji, Ipatagwa, Mambi, and Mswiswi rivers.

Issues

Decreased flows in the Great Ruaha have been recorded since the early 1990s, resulting in complete drying of sections of the river in 1993 and in dry years since (''illustration above''). This has been attributed to uncontrolled and poor water management, with the large rice irrigation schemes playing a major role. By 2019, the Great Ruaha experienced no water flow for several months per year. A report published by 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 ...

listed the Great Ruaha as an endowment in crisis due to environmental factors. Ruaha National Park Panorama

References

Sources

WWF.org - The Ruaha Water Programme

FAO - fact sheet on the ecohydrology of the Great Ruaha River (2003)
* Öhman, May-Britt, Taming Exotic Beauties: Swedish Hydro Power Constructions in Tanzania in the Era of Development Assistance, 1960s - 1990s, Stockholm, 2007, PhD Thesis, http://www.diva-portal.org/smash/record.jsf?pid=diva2:12267 {{Authority control Rivers of Tanzania Rufiji River