From the M62, Dream looks like a 65ft Tic Tac, poking out of a grassy slag heap. As you get closer, it grows features and hair — a young girl facing across the motorway towards a distant coal power station.

Sitting in a canvas chair, his can of Fosters clutched contemplatively, Ste approves. “It’s quite nice, like. I’ve a couple of grandkids I’ll take to see it.” Ste, who says only that his wife calls him Stephen (“and only then when I’m in trouble”), has broken off from a fishing trip to witness the unveiling. “I know it will have a pair of glasses on soon. Somebody’ll get up there; there’ll be a bit of red hair, a moustache.” Ste looks as if he would appreciate such additions.

Dream is one of the great success stories of the Big Art Project, a Channel 4 initiative that over the past four years has, in collaboration with local communities, commissioned seven public artworks around the country. Instigated by a group of former miners, Dream was created by the Spanish artist Jaume Plensa, and is already becoming a loved feature of the St Helens skyline.

The other six artworks have not been so successful. In Sheffield, the proposed canvases — two disused cooling towers — were demolished by their owners. In Cardigan, plans to fill the estuary with buoys that talk have caused a minor civil war.

Now one of the backers, the Art Fund, has organised a debate that asks the question that underpins the whole project: should people such as the miners of St Helens be given a say in public art; or is good art something that should be imposed by experts who know best?

Grayson Perry, one of the speakers at the debate, takes the elitist view. “Democracy has terrible taste,” he says. “One of the dominant strains in art is rebellion: antagonism to the status quo, mischief-making. The idea that that can be shoe-horned into a health and safety-certified piece of art for a bland public square is anathema.”

Part of Perry’s problem is that he is really not sure that he likes the idea of any public art. Andrew Shoben, however, his opponent in the debate, is the founder of Greyworld, a group with the specific goal of creating public art in public spaces.

“It is disgraceful,” he says of Perry’s views. “What arrogance; to say that you know best, that you can plonk work in a city and it will be liked.” He believes that it is essential that the people who will see the art every day are involved in its creation. “Public art has often been bronze statues or polished rocks of men holding swords. Why is there a highly polished rock? What is it to do with me? That is why there must be consultation, so that people can say, ‘That’s ours.’ Isn’t that what art is about?”

Where this debate leaves the theoretical — and enters the vitriolic — is in Cardigan. Channel 4 has big plans for Cardigan. Turbulence will be a collection of buoys bobbing in the estuary, connected to a microphone on the bank. The microphone will record what people say, to be played back whenever waves or tides move the buoys. This is supposedly a celebration of the Welsh oral tradition. Cardigan’s residents think it is more likely to be a celebration of the local youths’ capacity for swearing.

“What we find so sleazy is that it is being forced on us,” says Ralph Rea, a resident helping to run the “no” campaign. “The process of democracy has been usurped.”

He says: “This is so despised by the people of Cardigan, it will be vandalised. It’s going to end up with green algae and seagull s*** all over it, stuck in the mud, and spouting out four-letter words.”

Jim Evans, who instigated the work, accepts the level of opposition. “But this has been the case time and again for public art. You can’t convince people that their views will change, that they will come to love it.

“What we have shown here is that you can’t involve the public in public art. On a personal level, I am a democrat and I am discomforted by that position. But, ultimately, I think I am right.”

Big Art, Channel 4, Sunday, 7pm; the Art Fund debate “Can the public be trusted to choose public art?” is at the RSA, London WC2, May 20; www.artfund.org

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