An important goal of CleanSea was to provide policymakers and administrators in Europe with approaches for reducing the amount of plastics in Europe’s seas and oceans. Deltares was one of seventeen partners in the consortium.

Cleansea was the first integrated research project in this area in Europe and it focused on research questions like: How do you measure plastics?, How do they behave in water? and How quickly do plastics degrade? Socio-economic aspects are also being investigated, such as how much money or time bathers are willing to invest in leisure activities on plastics-free beaches.

Deltares has primarily been collecting new knowledge about the transport of larger and smaller pieces of plastic from rivers to the sea, and the degradation and fragmentation of plastic waste in a plastic soup we created ourselves. We have also looked at the effects of microplastics on parts of the food chain in both experiments and in ecological models (DEB models). We found out that the growth of microalgae is adversely affected at high concentrations of microplastics, but that there may also be adverse effects on the growth of zooplankton, organisms higher in the food chain. This means that the presence of plastics results in less food for animals such as fish in these areas. The plastics accumulate primarily in the coastal zone, both in the water and in sediment.

Cleansea involves collaboration with the Institute of Environmental Studies (IVM) of the VU-University of Amsterdam (NL), the University of Exeter (UK), EUCC Mediterranean Centre (ESP), Deltares (NL), KIMO (NL), ILVO (BE), Denkstatt (BU), University of Ӧrebro (SWE), Aegean University (GR), NILU (NO), Corpus data &image analysis (SWE), Callisto (UK), K/C Denmark (DE), EcoLogic (DE), ISI (NL), the Romanian National Institute for Marine Research and Development (RO), and HCMR (GR).