Marine litter is a clearly visible problem along the Baltic Sea coastline. It also appears under the surface and in many different size classes.

Around 70 % of the marine litter in the Baltic Sea is plastic. Plastic materials are of special concern due to their risks to the environment and slow degradation. Litter thrown on the streets will be flushed to the underground stormwater system during rainfall events.

As this system has been typically designed to convey water directly to the sea, all the litter that is in the water is also transported to the outlet. New technological solutions and approaches are needed to stop this pollution.