Assessing Nile Delta Coastal Region shoreline dynamics to inform urban resilience planning

The urbanized coast of the Nile Delta, a region of immense socio-economic importance, faces escalating threats from coastal erosion and accretion, driven by a confluence of anthropogenic pressures and climate change. This study presents an integrated, multi-method assessment of shoreline dynamics to analyze their implications for urban resilience. The research combines a high-resolution observational analysis of shoreline change using Sentinel-2 satellite imagery (2017–2022) with a process-based numerical model (LITPACK) to quantify the underlying drivers of littoral sediment transport and establish a regional sediment balance. Furthermore, future shoreline retreat is projected under IPCC RCP4.5 and RCP8.5 scenarios for near-term (2030–2040) and long-term (2050–2070) horizons. The findings reveal a complex pattern of coastal change, with a regional median erosion rate of − 0.8 m/year masking localized hotspots where erosion exceeds − 20 m/year. The numerical model quantifies the severe sediment deficit and transport gradients responsible for this erosion, particularly around the Rosetta and Damietta promontories, and validates these findings against observed shoreline changes. Projections indicate continued and potentially accelerated shoreline retreat, directly threatening critical urban infrastructure. The results demonstrate a critical disconnect between localized, hard-engineering adaptation strategies and the regional scale of the sediment deficit, which often exacerbates vulnerability in downdrift locations. This paper argues for a paradigm shift in coastal management, moving from a reactive, site-specific protection approach towards a proactive, integrated framework that prioritizes regional sediment management and nature-based solutions to build long-term socio-ecological resilience for the delta's urban centers.