CEDA Iberian Conference

Dredging for sustainable port development

Strategies for sustainable sediment management: the case of Port of Antwerp

27-28 October 2016, Lisbon, Portugal

Agnes Heylen, Port Authority Antwerp, Belgium

To meet the demands of an expanding harbor, the Port of Antwerp need to perform maintenance and capital dredging works in her area. 

The dredging demands of our expanding harbor are compiled in a business development plan, the so called nautical vision 2020. It’s partly as a result of the latest Scheldt deepening that also in the port area an access for vessels with a larger draft should be guaranteed. As a result, the extra volume due to capital dredging works, that will arise the next few years is estimated at 12 106 m3.

Due to historical industrial activities (e.g. shipyards, oil refineries, tank storage) a part of these sediments are polluted. As the sediments are partly the result of maintenance and capital dredging activities, the port will be confronted with both sandy and silty material.

The timely and well-defined vision 2020 provides the Port with the opportunity to move as a function of the dredging activities in a more proactive and sustainable way. A number of actions are set up: among other things an extended qualitative mapping of the sediment quality is performed, as well as the construction of site specific sediment risk assessment.

The purpose of the presentation is to zoom in on both of these projects. Both projects were carried out in collaboration with different stakeholders.

The project Ecodocks, carried out by the Antwerp University, implies the construction of a mathematic site specific risk model where both distribution (mainly to the river Scheldt) and ecotoxicology are calculated. This is mainly based on our own data collection, as well as on literature (e.g. Kd-values).

A large set of data are collected in order to have a mathematical idea on the turbidity influence of sailing/maneuvering, dredging activities and lock movements, in order to calculate the potential distribution of pollutants.

In the project mapping 294 samples were taken in the port area in order to have an idea of the current sediment quality and moreover on the evolution in sediment quality since 2002. Evolutions in time, parameters and location will be discussed.

Additionally, information will be given on the latest developments of the plant AMORAS, the large mechanical dewatering installation in the port area where investments have been carried out for better representation of today’s challenges.

Also, attention will be given to the progress the Port has made in reusing the produced filter cakes and the large lots of natural dried sediments, and the challenges it has faced.

Finally, the goal of the presentation is to give examples of the sustainable actions in relation to the nautical accessibility on the river Scheldt that were carried out in the last years, together with the Flemish authority responsible. The Port remains the main stakeholder.

The examples will emphasize the pairing of nautical accessibility and morphological issues, as well as issues of climate change in the Natura 2000 area.

Last update: 19 October 2016