We all know that there is a lot of plastic in our oceans. Together with a host of concerned organisations and members of the public, we have been working since our inception in 1990 to reduce marine litter. However, since plastics are distributed throughout the water column and break down over time into a ‘plastic soup’ it is impossible to completely clean up the plastic debris that is already in the oceans. As a society, we must therefore work together to reduce the input of plastic to the ocean quickly and efficiently.
In order to take practical measures to reduce plastic input, we need to answer two questions: ‘Where does it come from?’ and ‘How does it get into the sea?’. Dr. Christian Schmidt, a hydrogeologist at the Helmholtz Centre for Environmental Research addressed these questions in a study that appeared in a recent issue of Environmental Science & Technology journal. Dr Schmidt and his team analysed various scientific studies that examined the plastic load in rivers. They compared this data with the quantity of waste which is not properly disposed of in each river’s catchment area. “We were able to demonstrate that there is a definite correlation in this respect,” says Schmidt. “The more waste there is in a catchment area that is not disposed of properly, the more plastic ultimately ends up in the river and takes this route to the sea.”
The more waste there is in a catchment area that is not disposed of properly, the more plastic ultimately ends up in the river and takes this route to the sea.
The study also found that the correlation between river size and plastic load was not linear meaning that larger rivers carry disproportionately large amounts of plastic to the ocean. Any attempts to address the marine plastic pollution problem must therefore also address the inputs of plastic to our rivers. This seems like common sense but we now have the hard data to back it up.
Prof. Dick Vethaak introduces the huge and complex problem of plastic pollution of rivers and the sea (photo: Jan Joris Midavaine)
In order to curb the plastic pollution entering our rivers, KIMO Netherlands and Belgium organised and hosted the “No Plastic to the Sea” Conference which took place in the Hague on 30 November 2017. KIMO president Robert te Beest opened the conference and introduced an array of speakers with expert knowledge on the topic such as the Plastic Soup Surfer Merijn Tinga, Prof. Vethaak of Deltares, the VU University Institute for Environmental Studies (IVM-VU), and speakers from the Dutch Ministry of Infrastructure and Water (RWS), VNG (Association of Dutch Municipalities) and VNR (Association of Dutch Riverine Municipalities).
This was followed up by four topical workshops:
- Generating and keeping political support for tackling plastic pollution of rivers
- The components of an effective communications strategy regarding the problem of riverine plastic pollution
- Addressing local sources of riverine plastic pollution
- A plastic free Haringvliet Estuary (case study highlighting current steps being taken and exploring potential action gaps)
The workshops on “generating and keeping political support” and the “plastic free Haringvliet Estuary” generated cooperation agreements for reducing riverine plastic which was exactly the outcome we had hoped for. KIMO Netherlands and Belgium, together with their partners VNG and RWS would like to thank all participants for their valuable contribution. We look forward to facilitating further steps to tackle this huge problem!