Understanding and modeling the process of resuspension of fines in the coastal zone; case Khalifa Port

Abstract

=Introduction= Worldwide there is an increasing amount of dredging activities, due to increasing demand for transport of goods over the world. These project are more and more near sensitive nature reserves and thereby a potential threat of biodiversity; which is a major concern for port developers, authorities, environmental organizations and dredging companies. This research has emerged from the execution of Khalifa Port in Abu Dhabi; a project which lasted from February 2008 to July 2010. Turbidity in the water column (near coral reefs) was one of the main problems affecting Boskalis’ workability. Predefined, tight and fixed turbidity levels, valid for the whole site and execution period, were not allowed to be exceeded without adverse measures for the dredging company. The client had stated that the dredging company would always be responsible for the measured turbidity values; no matter what cause. An extensive data set resulted from this project. === Objectives === The aim of this research is twofold and can be related to the following research key objectives: • The goal of this study is to gain insight in the relevant processes that result in the behavior of fines. • Set up a simplified conceptual model be used as guidelines for future projects. === Approach === Research was done, following two approaches. First, the turbidity data set was analysed, where the relation was made with occurred hydrodynamics. The pre-dredging period was considered to capture the natural conditions leading a conceptual understanding. Understanding of Khalifa data can be used for in general guidelines for projects with similar environmental issues. Second, the behavior of suspended fines with a resuspension origin was simulated in an idealized model set up, this to improve understanding and secondly to create the ability to anticipate on turbidity events with regard to planning workability.