Water quality assessment and reuse potential of groundwater combined saline solution for irrigation

This study aims to evaluate the water quality and reuse potential of groundwater combined with a saline solution for irrigation. The brine dilution process was done by adding groundwater by determining the total dissolved salts (TDS) value according to the irrigation criteria and then by calculating the amount of groundwater to be added using the law of concentrations to obtain the water mixture, as the TDS value decreased from 4922 and 3810 mg/l to 2587 and 2200 mg/l, respectively. The assessment aimed to determine the suitability of the water for irrigation, and the quality indices used were sodium adsorption ratio, magnesium hazard ratio percentage, sodium percentage, residual sodium carbonate, permeability index, Kelly index, and irrigation water quality index. The results indicated that the water after mixing is suitable for irrigation. The USSL diagram was used to evaluate the post-mixing water at two stations, Touggourt and El-Oued, and the results showed that the post-mixing water at Touggourt falls in the C4–S1 group (extremely high salinity with low sodium), and the post-mixing water at El-Oued falls in the C4–S2 group (very high salinity with medium sodium).