The invitation was mouth-watering. “Come and join us on our rubbish dump! It’s next to a huge landfill site! In Croydon! You can build something out of rubbish while you’re here!”

This conjured up exciting associations: making a fort on the compost heap in my back garden as a boy; postnuclear holocaust survival stories; life in the shanties of the Third World or Samuel Beckett’s Happy Days, in which a character called Winnie spends the entire play sitting in a rubbish-topped mound.

The invitation was to the set of Dumped, Channel 4’s new environmental reality show, which runs this week from Sunday to Wednesday. It is an attempt to raise public awareness of the issue of excessive waste and the need for recycling, but in a fun, nonsermonising way. Eleven willing saps, sorry “volunteers”, answered strategically placed adverts, mainly on the internet, to spend three weeks on an “ecological challenge” at a mystery location.

They handed in their passports and were given injections. The night before their departure they were taken to a country house hotel near Gatwick, imagining they were off to Central America or the Congo. They were issued with survival kits, including a sleeping bag, billy-cans, one loo-roll each and a wind-up torch, loaded on to a coach with blacked-out windows and driven off to adventure. The first episode skips over their first reactions on arrival at the dump, possibly because of unsuitable language. Here they must build their own camp, including all facilities, using only what they can recycle from the rubbish around them. Those who survive the three weeks will share a £20,000 prize.

My visit comes halfway through their stay, and despite the initial trauma and the early loss of a tattooed joiner called Darren, they are in good spirits (Darren likes to put on brand-new underwear every day, but even he has learnt something before he leaves and resolves to send his discarded underpants to the Third World). I am with a small group of journalists, and the remaining eco-pioneers cluster around us like excited pupils at a school open-day, eager to show us their project work.

Their encampment sits in a landscape of specially constructed rubbish-hillocks, intersected by winding pathways, like the set of Teletubbies, but with garbage instead of grass. In fact, this is carefully chosen rubbish, representing a typical selection of British waste, but without the used nappies and putrefying food to be found on the real landfill near by. It also handily includes things like an old box of carpenter’s tools, plumbing pipes with snap-lock joints and a useful selection of dining chairs.

The day is hot and dusty, and the aroma of the gull-infested landfill hangs in the air. “The stench is appalling,” says Jarvis, an advertising executive, “first thing in the morning when the wind wafts through our tent . . . ”

After a first night on site in the luxury of an empty shipping container, the group managed to build a large A-frame tent, where they are still sleeping while they work on a bigger, more robust wooden shed.

Food was a potential problem. If they ate waste food from the landfill, they’d probably all be dead by now.

Researchers discovered that the typical Brit discards £424 of food a year, so on Day One a trailer arrived loaded with £424’s worth of comestibles. In the group’s open-air kitchen Sylvia, an eco-resort publicist, is stewing apples to eat with the breakfast porridge and enthusiastically describes their baked potatoes and the birthday cake they made last week.

The living area looks rather cosy. There’s a shelter covering tables loaded with their food supplies, seating arranged around the fire and, of course, a spa bath. Two of the group are pretty young blondes – this is infotainment after all – and part-time model Sasha explains how the bath works. They have drilled two holes in the side of an old tub. Pipes run to an old radiator propped on its side over an open fire. This heats the water, which bubbles back into the bath. It’s ingenious, if public. An exercise bike linked to a car alternator linked to a moped battery generates electricity for their light bulb, and I earn my keep with a full two minutes of pedalling.

The group can’t wait to show us the other facilities, starting with the lavatories. They are particularly proud of “the sh***er”, a seat over straw (which must be added to a compost bin and replaced after each use) in an open-air cubicle. Jason, a jeweller, wants to show off his improvements to the shower, which heats water in another old radiator embedded in a solar panel. An observing Jew, he has a special kosher sink for his ablutions and washing up.

It’s not all brilliant improvisation. They have been taught how to make these Heath-Robinson contraptions by an “eco designer” called Rob. Christine, a Scottish-Canadian artist-designer is obviously enjoying herself hugely, despite the pong. “It’s like one long sleepover party,” she says, taking me on a tour of their sports area, the video-diary tepee where she likes to meditate and shows me the pile of shiny metal things she is collecting to make an art installation.

This gets me thinking about my own rubbish project. The dump is vast. The possibilities seem endless, but I soon realise I simply won’t have time to rebuild my study using recycled plastic bottles. But for some reason the dump contains several mannequins, or mannequin legs. If I could create a surreal installation of my own I might be able to sell it to Charles Saatchi. The programme’s point is well made. You can do anything with recycled rubbish if you’re creative enough.

Dumped, Sun-Wed, C4, 9pm

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