Giant barriers keep waste out of the oceans

Barriers installed at the mouth of polluted rivers may seem a too simple solution to the growing plastic problem in the world’s oceans.

But for the Italian founders of an environmental startup, it is the very simple nature of the idea that could help spell the difference in the fight to save marine biodiversity.

A 2017 report published by the Helmholtz Centre for Environmental Research in Germany revealed that 90 percent of the over eight million tonnes of plastic that end up in the oceans every year have been transported there though one of the 10 most polluted rivers in the world.

Fabio Dalmonte, co-founder of startup Sea Defence Solutions or SEADS, says he came up with the idea during a research project on waste management in Jakarta, Indonesia.

He noted the huge amount of debris that floated on the Ciliwung River, which flows through the Indonesian capital.

"The mountain of waste that ends up in the Ciliwung and then in the sea, accumulating on the islands in front of the Gulf of Jakarta, ruins the beaches, damages tourism and causes serious problems to local communities,” he says. “Not to mention environmental damage such as a reduction of the fish population in the sea and the rivers."

Dalmonte says his idea was to stop the flow of plastic before it reaches the sea.

How else to do it but place barriers in the mouth of the rivers and send them to recyclers?

While the idea is simple, implementing it required thorough study and careful planning, with Dalmonte noting the need to ensure the system will not affect regular activities in the rivers.

To do this, he partnered with Mauro Nardocci, a business manager from Rome who now works in New York, to develop Blue Barriers, a system which they believe can be replicated in any river in the world.

“There are two floating barriers, positioned diagonally on the river and slightly offset, so as to create a current that transports waste to the bank, where a collection basin is built to accumulate, collect and then send the waste to be sorted,” explains Dalmonte.

The two barriers are made of recycled plastic, rigid and resistant enough to survive floods or the impact of large objects carried by currents.

Next to each couple of barriers, sorting centers will be created, which can also function to serve nearby communities and provide them with income from selling recyclable materials.

“In Jakarta and developing countries in general, many poor people collect their own waste to recycle and sell it,” says Dalmonte, “One of our parallel goals is to involve them in the activities that will be created around the barriers. We would like to make it possible for the municipality to include rag pickers in the waste collection system, providing them with adequate working conditions."

Ideally, Dalmonte said the barriers should be installed as close as possible to the mouth of the river, although these can be placed in other areas depending on the requirements of local governments.

A demonstration test will soon be conducted in Italy, on the Lamone river, and negotiations with the municipality of Jakarta to test the system on the Ciliwung are also well underway.

Soon, Dalmonte they hope their system would be adopted in other rivers, particularly in the 10 identified to contribute most to ocean plastic pollution. —  Elena Comelli, Corriere della Sera (Italy)

This article is being published as part of Earth Beats, an international and collaborative initiative gathering 18 news media outlets from around the world to focus on solutions to waste and pollution.