Coupled coastal modelling system and particle tracking model for shoreline morphodynamics and management at the Kitchener Drain Outlet, Northern Nile Delta, Egypt

Abstract

Sediment imbalance, hydrodynamic forces, and human-driven interventions have led to substantial morphological changes at the Kitchener Drain outlet, located on the northern Nile Delta coast of Egypt. This research employed a synthesis of the Coastal Modelling System (CMS) and the Particle Tracking Model (PTM) to simulate several engineering and nourishment scenarios, encompassing hydrodynamics, sediment transport, and morphological evolution. The model attained good predictive accuracy using wave, current, and sediment data from 2012 to 2013 for calibration, with a time step of 450 s, a Manning coefficient of 0.04, and the Van Rijn transport formula. Jetties, groins, spur dikes, and detached breakwaters were among the hard structures, alongside soft interventions, evaluated in six various scenarios. The most optimal compromise between upstream accretion and reduced downstream erosion was found in Scenario 5, which involved targeted replenishment with a sediment trap. Scenario 4, on the other hand, generated long-term stability with no net change due to the detached breakwaters. Nevertheless, other combinations, like Scenario 3 with spur groins, resulted in localized scour. After five years of simulations, the impacts of nourishment alone, particularly in high-energy zones, decreased in the absence of structural support. According to the findings, a hybrid management approach that incorporates both structural and nourishment measures is the best course of action for enhancing coastal stability and maintaining the Kitchener Drain discharge.