Lake Turkana

Lake Turkana () is a saline lake in the Kenyan Rift Valley, predominantly in northern Kenya; the far northern end crosses into Ethiopia. It is the world's largest permanent desert lake and the world's largest alkaline lake. By volume it is the world's fourth-largest salt lake after the Caspian Sea, Issyk-Kul, and Lake Van (passing the shrinking South Aral Sea), and among all lakes it ranks 22nd. Lake Turkana is now threatened by the construction of the Gilgel Gibe III Dam in Ethiopia due to the damming of the Omo River which supplies most of the lake's water.

Although the lake commonly has been—and to some degree still is—used for drinking water, its salinity (slightly brackish) and very high levels of fluoride (much higher than in fluoridated water) generally make it unsuitable for drinking; it has also been a source of diseases spread by contaminated water. Increasingly, communities around the lake rely on underground springs for drinking water. The same characteristics that make it unsuitable for drinking limit its use for irrigation.

The climate is hot and very dry. The rocks of the surrounding area are predominantly volcanic. Central Island is an active volcano, emitting vapour...