Determination of Selected physicochemical water quality parameters of the upper stream of Amerti watershed of Western Ethiopia

Abstract

Water quality is problematic worldwide. In densely populated areas, there is an enormous deterioration in water quality parameters due to human activities, urbanization, industrialization, and, waste disposal. The main objectives of this study were to determine the physical and chemical water quality parameters of the upper Amerti watershed in western Ethiopia. Water sampling sites were identified at four different sites based on land use, distances, and human activity and overall,16(4 × 2*2) water samples by composite sampling techniques were collected and some of them were measured in the field. Nine water quality parameters were selected purposively based on the problems of the area. Two replications and two water samples were carried out in the morning and afternoon based on water-stable flow time. As a result, built-up land had a greater impact on the physicochemical properties of the water when compared with other land-use types. Consequently, at water sample site two (S2), the mean of both Ca2+ and Mg2+ were beyond standard values and the Ethiopian guideline for drinking water (256.73 mg/L and 154.64 mg/L, respectively). Similarly, turbidity (NTU) was above the 5 UTN limit set by the World Health Organization (WHO), Canadian Council of Ministers of the Environment water quality Index (CCMEWQI), Oregon water quality Index (OWQI), and Bureau of Indian Standard (BIS). Correspondingly, Pearson's correlation matrix expressed that all physicochemical water properties were significant at (P<0.05) except total suspended solid (TSS) Mg/L due to land use. But the mean Ca2+, Ma2+, and turbidity were beyond standard limited value restricted by WHO, OWQI, and BIS as a general. since, water physicochemical properties varied site to site in the watershed, owing to the effects of land use, effluent wastes, and human activities. For this reason, to be environmentalism for our environment, it is the best option and in order to reduce such human and water quality problems, increasing awareness, establishing waste treatment plant must be needed to clean it and then, management of land use accordingly at watershed level is crucial for sustainability of the environmental resources and to maintain quality of water resource in the watershed for different purposes is necessary.