Yosef Abebe Yimer^1,, Abraha Geberkidan²

The aim of this study is to assess the current status of the Awash River. The study was desighned using 12 sampling stations for three consecutive months from December-2016 to February-2017. Samples were taken for physicochemical analysis from the main river and tributaries. All parameters have been analyzed using standard methods. High level of EC, TDS, NO₃^-, NH₃, Cl^-, SO₄^2-, Cr⁺⁶, DO, COD and BOD were recorded in station S04. Accordingly, EC in station S04, S07 and S09; nitrate in S02 and S04; chloride in S04 and S09; Na and alkalinity in S07, S09, S10, S11 and S12 exceeded the standard guideline limit of WHO and FAO. Some irrigation water quality parameters such as EC, %Na, SAR, RSC, HCO₃^-, and Cl^- concentration showed a progressive increase from station S10 to S12. Based on this investigation, it is concluded that the discharge of industrial, domestic, and agricultural effluents together with the expansion of Lake Beseka has strongly degraded the quality of Awash River at the study area. Untreated industrial wastes and unregulated lake water have caused significant pollution in the Awash River system and mitigation measures are required to restore good water quality.

water quality, degradation, untreated waste disposal, effluents and Awash River