Integrating river restoration goals with urban planning practices: the case of Kebena river, Addis Ababa

Investigation of Wabe River water fitness for agricultural and industrial purposes

The Wabe River is bordered by 74.84% agricultural area, and farmers rely solely on rainfall. The present research made an attempt to investigate the suitability of the Wabe river water for Agricultural and Industrial purpose. The suitability of river water for agricultural use was evaluated using the sodium adsorption ratio (SAR), potential salinity (PS), magnesium ratio (MR), Kelly index (KI), permeability index (PI), residual sodium carbonate (RSC), sodium percentage (%Na), and heavy metal pollution index (HPI). Additionally, the Ryznar Stability Index (RSI), Aggressive Index (AI), and Langelier Saturation Index (LSI) were used to evaluate the river water's suitability for industrial uses. Furthermore, plot the Gibb's diagrams to identify the sources of pollution and Piper diagrams to determine the hydrochemical composition of Wabe water. According to the HPI, pollution levels in the wet and dry seasons ranged from 53.34 (low) to 317.58 (medium) and 32.24 to 102.42 (low), respectively. The results showed that the Wabe River has very acceptable water quality characteristics and that the trace elements identified did not surpass thresholds that made them dangerous for agricultural usage. The findings showed that domestic wastewater and leachate contamination at sampling point W4 is the cause of the water quality deterioration in the downstream zone. The Ryznar Stability Index (RSI), Aggressive index, and Langelier saturation index readings were less than 9 at all sampling locations during both seasons, suggesting that the river water was corrosive, highly aggressive and unusable for industrial use without treatment.