Lake Rukwa is an
endorheic
An endorheic basin ( ; also endoreic basin and endorreic basin) is a drainage basin that normally retains water and allows no outflow to other external bodies of water (e.g. rivers and oceans); instead, the water drainage flows into permanent ...
lake located in the
Rukwa Valley of
Rukwa Region,
Songwe Region
Songwe Region (''Mkoa wa Songwe'' in Swahili language, Swahili) is one of Tanzania's 31 administrative Regions of Tanzania, regions. The region covers a land area of . The region is comparable in size to the combined land area of the nation state ...
and
Katavi Region in southwestern
Tanzania
Tanzania, officially the United Republic of Tanzania, is a country in East Africa within the African Great Lakes region. It is bordered by Uganda to the northwest; Kenya to the northeast; the Indian Ocean to the east; Mozambique and Malawi to t ...
. The lake is the third largest inland body of water in the country.
Geography
The alkaline Lake Rukwa lies midway between
Lake Tanganyika
Lake Tanganyika ( ; ) is an African Great Lakes, African Great Lake. It is the world's List of lakes by volume, second-largest freshwater lake by volume and the List of lakes by depth, second deepest, in both cases after Lake Baikal in Siberia. ...
and
Lake Malawi
Lake Malawi, also known as Lake Nyasa in Tanzania and Lago Niassa in Mozambique, () is an African Great Lakes, African Great Lake and the southernmost lake in the East African Rift system, located between Malawi, Mozambique and Tanzania.
It is ...
at an elevation of about , in a parallel branch of the rift system. Almost half of the lake lies in
Uwanda Game Reserve.
Hydrology
The lake has seen large fluctuations in its size over the years, due to varying inflow of streams. Currently it is about long and averages about wide, making it about in size. In 1929 it was only about long, but in 1939 it was about long and wide.
[Encyclopædia Britannica Online/Lake Rukwa](_blank)
/ref> During the early rifting of this part of Africa, the basin of Lake Rukwa may at times have been part of a much larger basin which also included the basins of Lake Tanganyika with Lake Malawi; ancient shorelines suggest a final date of overflow into Lake Tanganyika of 33,000BP. For overflow to occur again, the lake's elevation would need to exceed 900 meters. Overflow into Lake Malawi is not possible now, since the pass between the two basin stands at over 2000 meters elevation. (Neither Lake Tanganyika nor Lake Malawi can overflow into Lake Rukwa since they already overflow into the Atlantic and Indian Oceans respectively.)
There is an accumulation of heavy metals
upright=1.2, Crystals of lead.html" ;"title="osmium, a heavy metal nearly twice as dense as lead">osmium, a heavy metal nearly twice as dense as lead
Heavy metals is a controversial and ambiguous term for metallic elements with relatively h ...
like zinc, mercury, copper, lead, chromium, and nickel in sediment, water, and the muscle tissues of ''Clarias gariepinus'' (African catfish) and ''Oreochromis esculentus'' (Singida tilapia) in Lake Rukwa.
Helium discovery
In 2016, an estimated 1.53 billion cubic meters (54.2 billion standard cubic feet) volume of helium
Helium (from ) is a chemical element; it has chemical symbol, symbol He and atomic number 2. It is a colorless, odorless, non-toxic, inert gas, inert, monatomic gas and the first in the noble gas group in the periodic table. Its boiling point is ...
gas was discovered in Lake Rukwa worth $3.5 billion.
See also
*Rift Valley lakes
The Rift Valley lakes are a series of lakes in the East African Rift valley that runs through eastern Africa from Ethiopia in the north to Malawi in the south, and includes the African Great Lakes in the south. These include some of the world's ...
References
Lakes of Tanzania
Saline lakes of the Great Rift Valley
Geography of Katavi Region
Geography of Rukwa Region
Geography of Songwe Region
Freshwater ecoregions of Africa
Important Bird Areas of Tanzania
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