Using Simple Semi-Empirical Models for Integrated Assessment of Scenarios for a Navigation Channel: The Case of the Port of Ostend, Belgium

Abstract

Scenarios for a new navigation channel to the port of Ostend (Belgium) are to be assessed. Regarding coastal sediments dynamics, two aspects are of importance: first the maintenance dredging of the navigation channel itself (functional aspect), secondly the impact on the surrounding environment. The latter involves primarely the impact on the morphology of the sea bottom and the impact on the turbidity of the coastal waters. Available results of in situ-measurements, numerical modeling and laboratory experiments for the Belgian coastal zone were gathered, as well as general scientific literature. It could be concluded that the state of knowledge on coastal sediment dynamics in the Belgian coastal zone is to limited to be able to completely validate a process-based numerical model. A simple semi-empirical model was built, that is able to represent the essence of the impact on coastal sediment dynamics of a new navigation channel. INTRODUCTION The assessment of master plans of coastal ports comprises an assessment of the impact of scenarios regarding coastal sediment dynamics. A functional assessment as well as an environmental assessment are needed. Recent European legislation on environmental impact assessment (EIA) stipulates the use of a cascade approach in two steps : first an assessment of scenarios of masterplans (a strategic EIA) and secondly a more detailed assessment of scenarios of infrastructure works that implement a chosen master plan (a project EIA). This regulation –adding the concept of a strategic EIAaims at considerations of environmental impact already to be taken into account in the earliest stages of design.