Projections of Proper Beach Nourishment Volume as an Adaptation to Beach Recession based SLR along the Nile Delta Coastline of Egypt

Abstract

Sharaan, M. and Udo, K., 2020. Projections of proper beach nourishment volume as an adaptation to beach recession based SLR along the Nile Delta coastline of Egypt. In: Malvarez, G. and Navas, F. (eds.), Global Coastal Issues of 2020. Journal of Coastal Research, Special Issue No. 95, pp. 637-642. Coconut Creek (Florida), ISSN 0749-0208.Beach loss and shoreline recession-based sea-level rise (SLR) is considered one of the most critical coastal issues worldwide. The Nile Delta coastline of Egypt is categorized as a low-lying and sandy coastal area that is prone to impacts of SLR. Beach nourishment is considered one of the most common adaptation strategies for erosion mitigation. Sandy beaches have a significant role in tourism, recreational purposes, and disaster prevention. The projection of proper beach nourishment volume (fill density) as an adaptation to beach loss-based SLR and land subsidence using the Bruun rule were investigated along the Nile Delta coastline of Egypt. The ensemble-mean regional SLR data included Representative Concentration Pathway (RCP) scenarios. Three main steps were applied to estimate the required proper beach nourishment volume. First, the future beach width due to SLR was estimated, and vulnerable areas to shoreline retreat were identified. Second, the targeted beach width to be protected in terms of coastal conservation, tourism purposes, and maintenance of the present beach was proposed based on Egyptian polices. Third, proper sand beach nourishment volume was estimated for four RCP scenarios, when local land subsidence is considered. The results show that the proper volume of beach nourishment required to maintain the beach width along the whole Nile Delta coastline varies from 24.8×106 to 145.5×106 m3 in 2100, with respect to RCP2.6 and RCP8.5, respectively.