WINNIPEG -- Cities are both real and imagined places. What's interesting about Winnipeg and the reputation of its visual artists -- both those who have left and those who continue to live here -- is that the real and the imaginary have become indistinguishable. Because of the emergence on the international art scene of a group of artists, including Tim Gardner, Karel Funk, Jon Pylypchuk, Sarah Anne Johnson and Marcel Dzama and the Royal Art Lodge, Winnipeg is now viewed in New York, Los Angeles and London as a place that has produced an inexplicable number of good artists. There are rumours circulating about the water, the cold and the sense of community. All of them may be true.

What is unquestionably true, however, is that Winnipeg has developed a keen sense of itself as an art city, and the success of their peers is a model on which the current crop of artists can imagine how they might flourish in the rough-and-tumble art world. The most recent evidence of what those artists are up to is Supernovas. The Winnipeg Art Gallery and its adjunct curators Shawna Dempsey and Lorri Millan (who are themselves performance artists with an international reputation) have picked this stellar title as a way of focusing attention on "the future of art in Winnipeg" and on the basis of the quality and quantity of the work they have included, no one would disagree with that assessment.

But what is equally apparent is how thoroughly this group exhibition of 29 young artists is also about the "past of art in Winnipeg."

Winnipeg is, by and large, conservative, a predisposition that encourages the city's artists to use the past as a way of informing the present. Winnipeg artists also waste nothing; they are seriously committed to dumpster-diving and other forms of aesthetic recycling. Two-Sicks (the name is migratory and turns up as 26, Twenty-six and Too-Six), is a collective of some-time graffiti artists who ride around on bicycles in the summer and attach art pieces to walls, billboards and telephone poles in the inner city.

Two of Two-Sick's members, Shaun Morin and Fred Thomas, indicate the wide range that can be worked inside the surface chaos of urban art; Thomas uses aerosol paint to transform the refuse of the back alley -- tin-can lids and pieces of discarded metal -- into paintings of haunting, edgy beauty. Morin, who uses the tag Slomotion when he's on the street, can make elegant art in the studio as well. His ability to effortlessly yoke together the craggy figuration of the late Philip Guston with a positively formal sense of composition reveals him to be the most accomplished painter in the exhibition.

But that formal quality is everywhere apparent in Supernovas; in the collages of Justin Ludwar, the video of Heidi Phillips, in the deft Wite-Outing and cut-outing of Shawna McLeod's mixed-media drawings and the different registers of emotional restraint in the photographs of Meera Margaret Singh and Richard Hines. These 29 artists work in all media -- from Mike Germain's computer art to Jennie O'Keefe's doll-making -- but what emerges is a sense of intelligent control, a wariness that refuses to let the material and the process of art-making get out of hand. If these artists were members of a political movement, they would be old-style Red Tories.

There is a sense of restrained blueness in the exhibition as well. The back space of the gallery includes a clutch of artists who direct their attention to the body and its desires. Erica Eyres's ballpoint-pen drawings of young women are a disturbing species of fictional self-portraiture; while Liz Garlicki's large, loosely rendered vinyl-on-vinyl paintings of porn images are utterly compelling because they are so difficult to read. Porn shots that don't deliver are genuinely subversive, and it's in this territory of confused expectation and surprise that Paul Robles also works his tongue-in-cheeky magic. His two dozen meticulous origami paper-cuts on vellum are brilliantly naughty; inside the innocent form of the silhouette he executes a spectrum of sexual acts worthy of the Kama Sutra.

There is much to praise in this eclectic exhibition and much to be cautious about as well. The aesthetics of impoverishment -- how so many of these artists use the detritus of the street and punk culture -- is a way of making something out of nothing, but it can also become a style, a sort of material dumbing down. It can also become a way of simply gathering things together, which is not necessarily a way of making art. But at its most rigorous, the art of the overlooked and the undervalued can be delightful and dramatic. Adrian Williams, one of the founders of the Royal Art Lodge, is an older member of the new "supernovas." His mixed media on found material collages are a highlight of the exhibition, as is his expressed attitude toward making art. His method is "an attempt at resurrecting old objects with the clumsy magic wand of a new imagination." What he has always done in the past is a perfect description of what the "Supernovas" are so effectively doing in the present.

Supernovas continues at the Winnipeg Art Gallery until May 14 (204-786-6641).