Authors : Adimasu Woldesenbet Worako
DOI : 10.2166/wcc.2025.832
Volume : 16
Issue : 9
Year : 2025
Page No : 2726-2741
ABSTRACT Drought is a disastrous natural phenomenon that causes social, economic, environmental and political crisis to a given region due to water scarcity. This study presents the hydrological drought characteristics in the Ethiopian Rift Valley Lakes Basin by using streamflow drought index (SDI). The streamflow data were collected from 18 stations from Ministry of Water and Energy (MoWE) of Ethiopia. The SDI value was computed by employing the drought index calculator (DrinC) software and the trend of hydrological drought for three periods (SDI-3, SDI-6 and SDI-12) was detected by applying the non-parametric Mann-Kendall trend test and Sen's slope method. The findings of the study indicate that there was no significant trend on a seasonal basis, whereas there was significant increasing and decreasing trends on biannual and annual bases in Kulfo, Tikurwuha, Kola and Katar stations. The most common severe hydrological drought periods in the basin were 1984, 1985, 1999 and 2002 and the most common extreme drought registered years were 1984, 1986, 1991 and 2002. The probability of drought occurrence varies from catchment to catchment and timescales used. Hence, this study may provide basic information about the hydrological conditions that helps to develop better water adaptation and mitigation strategies in the basin.