Study to analyse the monitoring, assessment and identification of sources of litter in selected locations in 4 river basins within Europe.

Specific contract under Framework contract ENV.D.2/FRA/2012/0025

This report summarises findings of the project SFRA0025: Identification and Assessment of Riverine Input of (Marine) Litter for the DG Environment of the European Commission. The aim of the project is to investigate the level of pollution in EU rivers from plastic litter and to estimate the level of inputs of plastic litter from the rivers into four European regional seas.
Specific contract Duration From Until
Identification and assessment of riverine input of (marine) litter 10 months October 2013 August 2014
Under the framework contract:
ENV.D.2/FRA/2012/0025
Emerging pressures, human activities and measures in the marine environment (including marine litter)
Process
Four large rivers, discharging into different regional seas (North Sea, Baltic Sea, Mediterranean Sea and Black Sea) were selected for monitoring of meso- to microsized floating litter items. These rivers also belong to the group of important European rivers with respect to discharges. Rivers selected for monitoring were: Rhine, Dalålven, Danube and Po. 

For each river, a sampling location was chosen on a dominant branch in a river delta, within approximately 50 km of the mouth and, where possible, downstream of the last urban area and sewage treatment plant and downstream of the last tributary. The sampling was done in one two-week sampling period per river, except the Rhine, where sampling was done two times, according to the time and financial constraints of the project. On the Rhine samplings were done only during the outgoing tide, because in this region high tidal differences are present. 

In accordance with these criteria, the following sampling locations were selected:
  • Rhine –Rotterdam (3 times visited, 2 times sampled) - North Sea;
  • Dalålven - Ålvkarleby - Bothnic Gulf;
  • Po – Ferrara – Mediterranean Sea; and
  • Danube – Galati – Black Sea.
Three methods were used for monitoring to test the feasibility of the monitoring approach. Monitoring of floating microlitter was done with:
  • The manta net (mesh size 330 µm), especially modified for monitoring in rivers (Rhine, Danube, Po);
  • The pump-mantanet method (Dalålven and Po), where water was pumped through the manta-net, providing results on litter in suspension; and
  • With the Waste Free Waters (WFW) sampler(all monitored rivers). The sampler contains two metal nets (for surface and suspension sampling) with a mesh size of 3.2 mm.
3. Conclusions
This project has provided a quick-scan of the riverine environments in the EU and is one of the first projects that has looked at quantities of microsized litter in multiple rivers and compared them. We have demonstrated that plastic litter is found in all of the rivers sampled, even in the rivers with low population pressure (i.e the Dalålven). Since no threshold values for litter items exist, it is difficult to say whether the concentrations found are a cause for immediate alarm from an environmental perpective, more research is required to assess this. It can, however, be stated that rivers play an important role in transporting all sorts of litter items from the terrestrial to the marine environment, possibly also in the further fragmentation of larger litter items, and that management action is required if this input is to be decreased.
Coordinator:
Eunomia Research & Consulting Ltd
Bristol, UK
Website: www.eunomia.co.uk
Partners:
Ifremer, Deltares, Waste Free Waters , IWRS

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