Dr. Solomon Kibret
Chair, Global Coalition for Lake Tana Restoration
University of California, Irvine
Lake Tana is the largest lake in Ethiopia, accounting 50% of the country’s freshwater resources. It is approximately 84 km long and 66 km wide, with a maximum depth of 14 m and a surface elevation of 1,788 m above sea level. Its surface area ranges from 3,000 to 3,500 km² depending on season. The lake is fed by several rivers, with 97% of the water coming from four major rivers: Gilgel Abay, Ribb, Gumara and Megech. The annual inflow to the lake is estimated to be 4,986 Mm3 per year. The plains surrounding the lake (i.e. the Dembiya, Fogera and Kunzila plains in the north, east and southwest, respectively) form extensive wetlands favorable for large- and small-scale agriculture. As a result of the high heterogeneity in habitats, the lake and surrounding riparian areas support high biodiversity and are listed in the top 250 lake regions of global importance for biodiversity.
Lake Tana hosts 65 fish species – a quarter of which are endemic to the lake. Among them, it is home for eighteen species of barbus fish (i.e. of the Cyprinidae family) and the only extended cyprinid species flock in Africa. Other common fish species include tilapia (Oreochronmis niloticus) and catfish (Clarias gariepinus). A study in 1996 identified 217 bird species around the lake, with a minimum of 20, 000 water birds. The lake shore is also characterized by its extensive papyrus (Cyprus papyrus). Over 4 million people are estimated to live in the lake catchment and at least 15 000 people are believed to live on the 37 islands in the lake
The lake has tremendous socioeconomic benefits to the country. The major economic benefits include irrigation, hydropower generation, tourism and fishery. Several monasteries located in the lake’s islands have historical and religious assets. Studies show that the lake basin has an irrigation potential of 517,500 hectares of land. The potential fish production of Lake Tana is estimated to be 13 000 tons per annum. However, its current production is only about 1000 tons per year. Recent studies indicated a serious decline in fish stocks due to the spread of water hyacinth around fish spawning grounds.