The objective of the project is conducting a theoretical-computational and experimental investigation of the propagation of the wave disturbance, from the upwind leeward side of a coastal structure through renewal pipelines. The result of the project is the formulation of general fundamental equations, as well as building a numerical model of wave disturbance propagation in coastal structures through renewal pipelines, as a function of (a) wave characteristics, (b) the geometric characteristics of the renewal pipelines and (c) the parameters which take into account the shape of the coastal structure.