Precipitation and streamflow variability in Tekeze River basin, Ethiopia
Book Chapter
Fentaw, F, Melesse, AM, Hailu, D et al. (2019). Precipitation and streamflow variability in Tekeze River basin, Ethiopia
. 103-121. 10.1016/B978-0-12-815998-9.00010-5
Fentaw, F, Melesse, AM, Hailu, D et al. (2019). Precipitation and streamflow variability in Tekeze River basin, Ethiopia
. 103-121. 10.1016/B978-0-12-815998-9.00010-5
This research is carried out using nonparametric Mann-Kendall test and indicators of hydrologic alteration (IHA) to determine the potential trend and variability of precipitation and streamflow in Tekeze River basin, Ethiopia. Precipitation trend analysis result showed increasing trends for Annual, Kiremt, and Belg seasons whereas a decreasing trend in the Bega season throughout the basin. Tekeze River streamflow analysis also showed a decreasing trend in annual and dry season (October to January), and increasing trend in the wet season months. The IHA and range variability approach methods are used to evaluate the pre- and postimpact hydrologic regimes due to Tekeze River dam construction. The result showed that Tekeze hydropower reservoir operation significantly changed the hydrological regime downstream of the dam. Multiday minima streamflow increased, multiday maxima streamflow decreased, high pulse count decreased, and fall and rise rates decreased, number of annual hydrograph reversals increased, and the number and duration of high and low pulses increased. Hence, investigation of trends in the hydro-climatic variables of Tekeze basin revealed many significant trends, both increasing and decreasing. The findings may assist water managers in better planning and management of water resources under climate variability and change.
