GIS and REMOTE Sensing Based Water Level Change Detection of Lake Hayq, North Central Ethiopia

Abstract

This study investigates the response of Lake Hayq water level change over the period of 1972 to 2012. The purpose of this study was to show the water level change of Lake Hayq and the management practices for this change. The water level change of Lake Hayq was assessed by examining the water balance of the lake. Precipitation, runoff from the watershed area, evaporation and surface outflow from the lake are the major components of water balance of Lake Hayq. Penman’s combined energy balance and mass transfer approach formula was used to calculate annual evaporation rate of the lake. The resultant of water balance of the lake Hayq show that annually 0.9×10⁶ m³ of water misplaced from the lake. The width of the isthmus of Lake Hayq has increased from 33 meter, to 108 meter and 163 meter in the years 1972, 1986 and 2012 respectively.  As such, any fluctuations in the area and the level of the lake can be imposed by both natural and anthropogenic forces. Some of the natural factors are drought, topography of the watershed, erodibility of the soil, and variability of the rainfall. Some of anthropogenic factors are over pumping of the lake water for irrigation, inappropriate use of wetland, LULC change and deforestation. In order to keep the natural balance of the area wetland management in the buffering zone, studies based use of lake water for irrigation, afforestation, and soil conservation program are must be needed.

Keywords: Water Balance, lake level,  Lake Hayq,  Ethiopia