The present study focuses on the analysis of physicochemical and biological water qualityrnparameters: electrical conductivity, nitrate, phosphate, COD, BOD, DO, turbidity , totalrndissolved solids, total alkalinity, total hardness, trace elements and biological parameters likernE- Coli and total coliform in the upper Awash River basin. Awash River is in a greatrnenvironmental concern because most of its tributaries streaming from the different catchmentrnarea of the basin contain several pollutants. The main threat to the surface water quality in upperrnAwash River basin is environmental pollution derived from domestic, Industrial and Agriculturalrnactivities. Due to inadequacy of controlled waste management strategies and waste treatmentrnplants, people are forced to discharge wastes both on open surface and within water bodies.rnImproper waste disposal has deteriorated the quality of Awash River by changing the physical,rnchemical and biological properties of river water. Twelve samples of river water from differentrnselected points during dry and wet season were collected and taken to Addis AbabarnEnvironmental protection laboratory and Oromia water quality laboratory for identification ofrnsurface water quality status. physicochemical and bacteriological analysis of the samples duringrnthe dry and wet season along the streams show that the level of unwanted chemical andrnbiological constituents are higher than the maximum permissible limit of Ethiopian and WHOrnstandards. Therefore, this study aims to assess the quality of Upper Awash River Basin surfacernwater quality based on physicochemical and bacteriological parameters and figure out if therernare environmental and health risk associated with the use of these water sources. The resultrnindicated that the range of BOD (7.6-216mg/l), Ammonia (0.12- 44.8mg/l), phosphate (0.28-rn9.64mg/l), turbidity (104- 5100mg/l) and alkalinity (40- 438mg/l). Total coliform and E-Colirnpresent in the samples were at levels indicative of fecal pollution. It also exceeded all thernguidelines for human use whether for personal contact, drinking, washing and cooking.rnTherefore this indicates that there is a serious health risk from the use of these water sources.rnThe lack of industrial and municipal wastewater treatment plant of the towns in the basin hasrncaused the Awash River to suffer from a serious pollution.