We push off from the quay by Amsterdam’s Westerkerk, leaving the tourist bustle and long, fidgety queue for the Anne Frank House behind us. Our little electric boat heads quietly south down the Keizersgracht canal for a tour of the city. Our guide, Erik, points out the sights: a famous hotel, a secret church, the seven bridges view but we are distracted, focused on the plastic debris that bobs by our boat. As with more than 15,000 people before us, we have jumped on board one of Amsterdam’s most unusual boat trips: a plastic fishing tour of the canals – and we are eager to see what we can find.

Unlike the slippery perch who flit deep beneath us, the docile plastic is an easy catch. From our open-topped boat, nets in hand, we haul in the flotsam. If we had orange jumpsuits on, jokes Erik, we’d look like we were doing community service. In fact, I’m travelling with seven tourists who have paid to collect rubbish as part of their holiday.

Children take a trip to clean the waterways Photograph: PR

Founded by Marius Smit in 2011, Plastic Whale runs plastic fishing tours in Amsterdam and Rotterdam. While travelling across Asia in his 30s, Smit, now 45, was shocked by the plastic pollution he saw and wanted to make a difference. When he returned to Amsterdam and noticed all the plastic in the canals, he realised the problem was closer to home than he had thought.

The Amsterdam water company, Waternet, has estimated that around 3,500kg of rubbish is removed from Amsterdam’s waterways each day. “About 80% of what is floating out at sea comes from cities around the world,” says Smit. “My conviction was that there were millions of people like me who wanted to contribute [to change that] in a positive way.”

Anne Jakobsen from Copenhagen, fishing alongside me, is a good example. She and her husband, Ole, have brought the family along “to lift the carbon footprint we leave behind. And show the kids you can do something other than the Rijksmuseum,” she says.

Marius Smit, centre, in a publicity image for Plastic Whale. Photograph: Natasja Noordervliet

Rolling up your sleeves and helping a city dispose of its waste may not sound like a fun way to experience a destination but the tour – which claims to be the first of its kind – is surprisingly popular. Plastic Whale has seen a surge of interest as awareness of the plastic crisis has grown. And with the announcement today of the world’s first plastic-free supermarket aisle opening in Amsterdam, the city is now seen as a leader in the fight against plastic pollution. In 2017, its Amsterdam fleet of nine boats took 6,000 people fishing for plastic, plucking 50-60,000 PET (polyethylene terephthalate) bottles out of the water and nearly three times this volume in other waste.

Around 8,500 rescued bottles have been used to make the plastic boat we are travelling in. It’s a circular solution to the problem: the more plastic collected, the more boats can be built and the broader the clean-up operation.

Erik is full of interesting anecdotes about the city and the objects they have found in its waters. Since plastic fishing began, he tells us, the canals have revealed an underworld of wallets, passports, and car keys discarded by thieves or dropped by drunken tourists. One passenger shrieked when she mistook a submerged mannequin for a dead body and they once found a bottle containing an envelope addressed to Germany. They put it in the mail but are yet to receive a reply.

Our loot is less exotic. We have a parsnip, some cans and a small sachet of weed labelled “Dr Grinspoon”, sieved from the water by nine-year-old Gus Krohn from Minnesota, who is unfamiliar with this quintessentially Amsterdam item. Later Gus enjoys what he calls “a pirate takeover” as we leap onto an abandoned boat covered in trash and rob it of its plastic booty.

Spiffing work … Gus having fished out ‘Dr Grinspoon’. Photograph: Jake Krohn

“Plastic fishing has a positive impact on kids, they love it,” says Smit. “As soon as they take the plastic out of the water, they see it doesn’t belong there. When we tell them that we make boats out of it they understand it should be seen as a raw material, not as waste.” Today, around a fifth of their trips are with schools.

Visitors keen to try out the plastic fishing tour should sign up soon. As the Plastic Whale fleet expands, plastic will become scarcer and may eventually bring about a natural end to the activity. But for Smit, the Plastic Whale’s extinction is part of the mission. He is already investigating moving the concept to Indonesia or India, where he says “poverty and waste go hand in hand”.

“We exist to solve a problem,” he says. “We want to go out of business.”

• plasticwhale.com. Two-hour trip £23pp, includes snack and drinks

Keep it clean: environment-focused events in the UK

The sea and shore seen from Birling Gap, East Sussex. Photograph: Joas Souza/Getty Images

For an eco-conscious stroll in the UK, from 2-4 March there is the annual Great British Spring Clean, with hundreds of events around the country coordinated by the Keep Britain Tidy campaign. These include events at National Trust properties, from beaches and heaths to parklands, including a litter pick at Badbury Hill, Oxfordshire, Birling Gap in East Sussex and Rhossili on the Gower peninsula. From 7-15 April, Surfers Against Sewage organises the Big Spring Beach Clean, which involves more than 1,000 beach cleans around the UK and, since launching in 2010, has removed 152,741kg of rubbish. The charity also organises a beach clean in autumn. In a similar vein, on the third weekend of September the Marine Conservation Society runs the Great British Beach Clean with litter picking events at more than 300 beaches.

Will Coldwell