The Dutch town of Katwijk has installed a 'bubble barrier', otherwise known as the 'Great Bubble Barrier', in the Oude Rijn river in the town. The idea began in 2018, when local citizens became concerned about the amount of plastic pollution. Eventually, they invited councillor Jacco Knape of the municipality of Katwijk to take part in plastic cleanup activities.
Taking part in the cleanup activities allowed the councillor to see the plastic problem with his very own eyes. After this, support continued to grow, which would eventually lead to the development of 'The Great Bubble Barrier'. The first Bubble Barrier is now fully operational in the Dutch town of Katwijk, just one kilometre from the North Sea.
The Great Bubble Barrier works by using three main components: the bubble curtain, the compressor, and the catchment system. Using compressed ambient air from the air supply, air is pumped through a perforated tube at the bottom of the river, creating a 'bubble curtain'. These bubbles push the plastic upwards toward the surface of the river.
It is placed diagonally across the river, so that the natural flow of the river will help to push the plastic waste to the side, where it enters the catchment system. The plastic is then gathered from the catchment system to be processed and reused.
The Great Bubble Barrier boasts several benefits:
- The system uses renewable energy wherever possible, which is kinder to the planet.
- It operates 24 hours per day, 7 days a week.
- It allows fish to pass through safely.
- Increases levels of dissolved oxygen, which benefits the aquatic ecosystem.
- Open for ship traffic and causes no obstruction.
- The barrier extends across whole river.
- It is versatile and can adapt to a variety of infrastructures.
- It is suitable for various river types.
The Great Bubble Barrier is also effective against microplastics which measure as small as 1 millimeter, up to 1 meter. It is also effective at catching up to 86% of plastic, past studies of the system have shown. In 2022, they are expecting to receive results from further tests which will give them more data on the new technology.
Other technologies around the world are also being developed to help prevent pollution in our seas and rivers, for example, seaweed farms are helping to combat nitrogen pollution in river estuaries.