Investigation of the Wabe River water’s suitability for drinking purposes and aquatic life and detection of pollution sources

Abstract

Abstract Wabe River is a vital source of drinking water, irrigation for agriculture, and income for the local residents. However, the river's declining quality has led to an increase in waterborne infections and made it appear muddier. The study's objective was to evaluate the Wabe river water quality using 23 different water quality parameters to calculate the Weighted Arithmetic Water Quality Index (WAWQI), Metal Index (MI), Pollution Index (PI), and Potential Ecological Risk Index (PERI). The origins and hydro-chemical makeup of the river water were also ascertained using Piper diagrams and Gibb's plots. During the wet season, the WAWQI results revealed that the River water is unfit for drinking, which range from 205.4 to 487.8 (> 100) at all sampling stations. During the dry season, the water quality ranged from good to unsuitable (48.7–101.4). Similarly, the results of the Metal Index were greater than 1(MI > 1) indicates ‘Threshold of warning’ for drinking and aquatic life in both seasons. Pollution index results showed ‘seriously’ effect on aquatic life. However, the risk level posed by those metals according to PERI was in the range of 436.9 (Strong) to 1714.1 (Very high) and 288.5 (Moderate) to 704.3 (Very high) during the wet and dry seasons, respectively. The sources of contamination were confirmed by Gibb's plots as rock weathering, evaporation, and anthropogenic activities, and the water type was classified as calcium-magnesium-chloride by the piper diagram. Controlling the sources of pollution is necessary for preserving the Wabe River's sustainability.