Assessing the coastal impact of port development and dredging activities.

Abstract

The construction of the Tangier Med port complex, Morocco's largest Mediterranean port, ignited concerns about its impact on nearby Dalia and Ksar Sghir beaches. This study investigated the morphodynamic changes of these beaches to determine the port's influence on their shoreline dynamics.Employing a multi-temporal approach, we analyzed shoreline changes across two distinct periods: 1988-2022 (pre- and post-construction) and 2013-2022. The first period leveraged aerial photographs, satellite imagery, and the Digital Shoreline Analysis System (DSAS) within a comprehensive Geographical Information System (GIS) framework. Erosion rates were quantified using established indices (NSM, EPR, LRR).Intriguingly, DSAS revealed a consistent erosive trend across the entire period, but with significantly higher rates before port construction. This suggests a potential stabilizing effect of the port complex and associated offshore dredging, potentially mitigating the impact of frequent storms and intense waves observed in the earlier period.Detailed topographical surveys in 2012 and 2022 corroborated these findings, revealing overall coastal stability with minor fluctuations attributed to meteorological and riverine factors. This highlights the complex interplay between human-induced infrastructure development and natural forces in shaping these beaches' evolution.This study underscores the critical need to consider both natural and anthropogenic factors in coastal management and planning. While the Tangier Med port complex and dredging may have contributed to shoreline stabilization, neglecting the influence of natural events, particularly in the pre-construction phase, could lead to inaccurate assessments and potentially unsustainable coastal development.