Modeling the dispersion of wastewater pollutants in Gaza's coastal waters

The disposal of sewage water in Gaza City has emerged as a significant issue with extensive environmental repercussions. This study seeks to investigate the pollution plume resulting from the discharge of untreated or partially treated sewage water through Gaza City's main outlet into the Mediterranean Sea. Additionally, it aims to predict scenarios for various design configurations of submerged outfalls with either single-port or multi-port diffusers and compare these scenarios against the Environmental Protection Agency (EPA) recreational water quality criteria. According to the EPA, the concentration of Enterococci bacteria at the edge of the mixing zone should not exceed 35 CFU/100 ml to minimize the adverse environmental impact on the marine ecosystem. CORMIX software was utilized as a modeling tool to simulate the dispersion and attenuation behavior of pollutants resulting from this process and to conduct a sensitivity analysis to optimize the design configuration of the sewage disposal system. The simulation considered the influence of ambient conditions (ambient velocity, wind, and seawater density), effluent characteristics (density, flow rate, pollutant concentration, and pollutant decay rate), outfall configuration, and sea bathymetry. Simulation results indicate that a single-port diffuser is unsuitable according to EPA recreation standards. Multi-port unidirectional diffusers, extending 490 m from the shore into the water, meet the required standards. To a lesser extent, the multi-port staged distributor also meets the standards and is more recommended for counter-current situations. •Environmental Impact Assessment: The paper addresses the significant environmental repercussions of sewage water disposal in Gaza City, highlighting the urgent need for effective wastewater management solutions.•Modeling Pollution Dispersion: It utilizes CORMIX software to simulate the dispersion of pollutants from sewage discharge into the Mediterranean Sea, providing a detailed analysis of how different outfall configurations affect pollution levels.•Comparison with EPA Standards: The study compares various design configurations of submerged outfalls against the Environmental Protection Agency (EPA) recreational water quality criteria, specifically focusing on Enterococci bacteria levels.•Design Recommendations: Findings suggest that multi-port unidirectional diffusers extending 490 m from the shore meet EPA standards, while single-port diffusers do not. This p