Assessment of secondary wastewater treatment technologies for agricultural reuse in Rafah, Gaza Strip: Application of evidential reasoning method

Abstract

Water scarcity is a global issue confronting the present generation, particularly acute in arid regions such as Palestine. Treated wastewater reuse is recognized as a strategic solution. The challenge in obtaining effluent quality that meets the reuse requirements of the area is how to select the best treatment technology. A multi-criteria decision-making method is necessary for assessing the sustainability of different wastewater treatment technologies. This study selected the most sustainable secondary treatment technology that could produce quality effluent for agricultural reuse at the Rafah wastewater treatment plant in the Gaza Strip. The Evidential Reasoning method was applied to evaluate the sustainability of sand filters, constructed wetlands, activated sludge, and bio-tower technologies. The evaluation was based on four sustainability dimensions and thirty-five indicators. The dimensions and indicators were obtained from a review of related literature and validated by experts. Using a questionnaire, the judgment of local experts (professionals working on the project, selected university professors, and members of the agricultural NGOs) was used to evaluate the dimensions and indicators qualitatively. Data analysis was done using the Intelligent Decision System and Expert Choice software tools. The utility interval-based evidential reasoning ranking technique was used to rank the wastewater treatment options with and without ignorance as follows: constructed wetlands > sand filters > bio-towers > activated sludge. Constructed wetlands ranked as the most sustainable alternative, with a minimum utility of 0.7345. The environmental dimension, with a relative weighting of 60.4%, was the dimension with the greatest influence on ranking the secondary wastewater treatment alternatives.