It was once a shoreline buried by enough trash to render it invisible, warranting the unfortunate nickname “toilet bowl”. Now the Philippines' Manila Bay beach is unrecognisably clean compared with a few months ago, a transformation so sudden and extreme that it brought tears to the eyes of residents.

The clean up started on 27 January, when 5,000 volunteers descended on Manila Bay to remove over 45 tonnes of garbage, marking the beginning of a nation-wide environmental rehabilitation campaign. But some two months before this massive movement began, a quiet revolution was already underway.

During the first week of December 2018, Brooklyn-based Bounties Network collected three tonnes of trash from Manila Bay over two days through a pilot project that paid a small network of people, mostly fishermen, for each cache of trash with a digital currency based on the Ethereum system.

You might also like:

For the mostly non-bank-using Filipino fishermen, this was a first-ever experience with a cryptocurrency. It’s one that could prove decisive in enabling poor communities around the world to take up arms in the fight against humanity’s waste, starting at the source of the bulk of global ocean pollution.

There are signs that this recycling-for-digital-payment industry may be just about to take off. Earlier in September 2018, Plastic Bank, a Vancouver-based blockchain company powered by IBM technology, also launched a similar inaugural project. They set up a scheme in Naga, a town in southern Luzon, the country's largest island, establishing a permanent collection point to let people trade plastic and recyclable materials for digital payouts through a reward system. Shaun Frankson, co-founder of Plastic Bank, says three more similar locations will open near Manila Bay over the next six months.