<p>This study examines the environmental impacts of industrial and maritime pollution on the Nile River ecosystem, specifically focusing on how pollutants affect fish habitats. A two-dimensional mathematical model that analyzes the connection between dissolved oxygen levels and pollutant dispersion in river systems has been created. The model combines advanced numerical methods with analytical solutions to track pollution spread from various sources, including factory discharges and ship emissions. Our findings reveal five distinct ecological zones along the river, each with unique characteristics that determine fish survival and distribution. Particularly concerning is the identified septic zone where oxygen levels drop too low for most aquatic life. The research demonstrates how water flow speed and aeration techniques significantly influence pollution patterns, with faster flows increasing pollutant spread upstream while potentially improving conditions downstream. These insights provide water resource managers with practical tools to predict pollution effects, identify critical intervention points, and develop targeted strategies to protect vulnerable fish populations. The model's adaptable framework can be applied to similar river systems worldwide facing pollution challenges, offering a scientific basis for balancing industrial activity with aquatic ecosystem conservation.</p>