Seasonal water quality index and suitability of the water body to designated uses at the eastern catchment of Lake Hawassa.

The availability of quality water is imperative to human health and ecosystem functioning. This study was aimed at determining the water quality index and examining its suitability to different water uses. Water samples were collected in dry and rainy seasons to capture the influence of seasonal variation. Water quality indicators (pH, electric conductivity (EC), temperature, total dissolved solids (TDS), turbidity, total suspended solids (TSS), nitrate, phosphate, and ammonia) were analyzed in the laboratory, and weighted arithmetic index method was employed to determine the quality index. The water quality index (WQI) showed higher value 870.3 and 1,313 for dry and rainy seasons which indicates that the water is unfit for human use, and the status of the water body is hypereutrophic. With cautions handling, the water appeared to be suitable for irrigation and livestock production but undesirable for aquatic life and resulted in an impairment of the ecosystem. The statistical analysis revealed a significant difference in water quality parameters between dry and rainy seasons (p < 0.05). The overall water quality status demonstrated concerns that could pose a significant risk; hence, measures should be taken to improve the quality and manage water to safeguard human health and environmental safety.