Water level fluctuations of Lake Tana and its implication on local communities livelihood, northwestern Ethiopia

ABSTRACT

Lake Tana is a shallow inland lake with an average depth of 9 m. It is fresh water lake with the total area of 3150 km².The lake level has experienced a rapid water level fluctuation in recent years. The study was aimed at analysing the water level fluctuation of Lake Tana. Four Landsat images acquired at different times from the United States Geological Survey have been processed and analysed by using the ERDAS and ARC-GIS softwares to detect changes in the lake area through time. In addition to this, the long-time lake level and climate data obtained from National Metrological Agency were analysed using a linear regression model to complement the lake level change. Focus group discussion, key informant interview and direct observation were held to analyse the impact of lake level fluctuation on the livelihood of the community. The result of the study indicated that more than 180 km² of Lake Tana area has been converted to farm and other land uses during the last 35 years. The climate variability has been observed for the study period. There was continuous lake level fluctuation because of land-use changes, climate variability and water regulation for hydropower productions. Water level fluctuation of the lake had impacted on land use and its environment. The land use and regulated water at Chara Chara weirs, which are the contributing factors for Lake Tana water level fluctuation, should be managed regularly and critically.

Abbreviations: ERDAS, Earth resource dynamic analysis system; GLCF, Global Land Cover Facility; FGD, Focus Group Discussions; IPCC, the Inter-Governmental Panel on Climate Change

KEYWORDS:

• Chara Chara
• lake level
• Lake Tana
• remote sensing
• water fluctuation

Disclosure statement

It is the sole work of the author and all sources are acknowlegded.