Dredging encompasses all the work involved in removing and depositing sand, silt and other layers on the waterbed. This technique is mainly used for maritime access and coastal defense, but also for land reclamation and nature development. Globally, more than 99% of the sediment deposited into the sea comes from dredging of ports and navigation channels. Between 2008 and 2014, more than one thousand million tons (dry weight) of dredged material was deposited in the OSPAR2 region (Northeast Atlantic and North Sea) (OSPAR IA 2017). A large part of these sediments were dredged and deposited in the southern part of the North Sea, which is largely due to the maintenance of the shipping channels to major seaports such as: Hull, Zeebrugge, Rotterdam, Bremen, Emden, Hamburg, Esbjerg, etc. (OSPAR QSR 2010). In the Belgian part of the North Sea (BNS), 10.9 million tonnes (dry weight) were dumped in 2017 (Lauwaert et al. 2019). The evolution of the amount of dredged material deposited in the BNS has been monitored by the Management Unit of the Mathematical Model of the North Sea (RBINS-BMM) since 1991.  Due to the ever-increasing volume, there needs to be strong regulation on exactly where and how much material can be dumped. In the marine spatial plan (MSP 2020-2026, RD of 22 May 2019 see also Verhalle and Van de Velde 2020), five zones for dumping dredged material were delineated: Bruggen en Wegen Zeebrugge East (ZBO), Ostend (OST), Nieuwpoort (NWP), S1 and S2 . In addition, the MSP also defines a number of search zones for dumping dredged spoil, which can be used to relocate or optimize the existing dumping zones S1, Bruggen en Wegen Ostend, Nieuwpoort and Zeebrugge Oost.

For more information we refer to the thematic chapter 'Dredging and dumping' of the Compendium for Coast and Sea.

Marine Spatial Planning
Dredging and dumping sites and intensity