Morphodynamic Modelling of Bottom Evolution Around a Low Crested Structure. José M. Alsina, Agustín Sánchez-Arcilla, Daniel González, Iván Cáceres, Joan P. Sierra and Cesar Mösso Laboratori d’Enginyeria Marítima, ETSECCPB, Universitat Politècnica de Catalunya, c/. Jordi Girona 1-3, Campus Nord ed. D1, 08034 Barcelona Tel: +34 93 401 6468 Fax: +34 93 401 7357 E-mail: jose.alsina@upc.es , agustin.arcilla@upc.es , daniel.gonzalez-marco@upc.es , i.caceres@upc.es , joan.pau.sierra@upc.es , , cesar.mosso@upc.es Abstract In this paper a study of a beach morphological response modelling protected by a low crested structure (LCS) is presented. Different test cases have been performed with the aim to evaluate the performance of the numerical model suite involved in the modelling process. Introduction The coastal area of Catalonia is an important economic and social resource, due to the interaction of different interests (social, economic and environmental). One of the principal problems that frequently coastal managers have to tackle at the Catalonian coast is the erosion of the shoreline and the lost of beach surface. Several reasons have been argued as the cause of this problem. Among them, the following are