VANCOUVER -- How many artists would want their work associated with the swill draining through a city's sewage system?

Quite a few, it turns out, at least in Vancouver, where 643 responses were received from professional and amateur artists to Art Underfoot, a competition to design two new cast-iron manhole covers for the city's storm and sanitary sewer systems.

"We thought we'd receive maybe 300 submissions," says Barbara Cole, the project manager with the City of Vancouver's Public Art Program.

"We didn't know what to expect. At first you might think 'Who wants art on sewer covers? How mundane.' But man, it's going to be great," she said.

"I think it will make a huge difference to the city. People from out of town will notice them immediately, I'm sure. I think there's some real lasting value in the designs that were chosen."

The two winning designs - selected from a shortlist of 30 -- will be unveiled this evening at Vancouver's Roundhouse Community Centre, where all 643 submissions are on display until Saturday.

The two chosen artists will each receive a $2,000 prize. Their designs will be turned into an aluminum mould and sent to a foundry in China, where the patterns will be mass produced into cast-iron discs that weigh approximately 100 kilograms and are expected to last for about a century.

The $20,000 project follows the lead of a growing number of cities to commission designer lids for their sewage systems that include Calgary, Seattle, New York and Tokyo.

"It's a mark of sophistication for a city to think of including artists when they're designing a manhole cover," says Daina Augaitis, chief curator of the Vancouver Art Gallery and one of the four jury panel members that included aboriginal artist Sonny Assu, Suzuki Foundation executive director Jim Fulton and writer/designer Douglas Coupland.

"Why not use an artist instead of a city engineer?" says Augaitis. "It adds to a city's consideration of itself."

In addition to sprucing up Vancouver's infrastructure, the competition was intended to raise awareness around the city's efforts to separate sanitary and storm-water sewer pipes over the next 46 years. Once completed, the project will prevent sewage overflows from polluting local waters during heavy rain.

The two new designs will be rolled out slowly when the city's 25,000 existing manholes need replacing or the network is expanded. It will mark the separate systems -- one for storm sewers that carry runoff rainwater, the other for sanitary sewers that carry waste from homes and businesses.

The competition was open to anyone who lived, worked or went to school in Vancouver.

It thus reached far beyond the city's artistic community to include amateur designers and even several school projects. Cole says that only about one-third of the submissions were from recognizable artists.

To give everyone a fair shake, the entries were juried blind. And given the manhole's long life expectancy, the jury was asked to select relatively classic designs that worked with the circular format and could be easily translated to the aluminum mould.

"It was important to us that these manhole covers somehow speak of Vancouver," explains Augaitis, adding that the jury selection was "fun" and surprisingly quick.

The more common motifs included raindrops, puddles, spirals, herons, crabs, whales, first-nations symbols and references to the 2010 Olympics.

"There were some great abstracts, and some that were more conceptually oriented," she explains. "They might work in a gallery, but not so well in the streets.

"I think we considered all of them -- even having a kid's drawing out there would have been quite delightful. In the end, we chose two quite sophisticated designs that were complex and interesting and beautiful to look at."

With any luck, Vancouver's new designer manhole covers might become as popular as they are in Vail. Earlier this month, the Colorado ski-resort town rolled out its new 16-piece Vail Manhole Cover Jewellery line. The sterling silver charms and cufflinks are miniature replicas of manhole covers that feature the town's "V" logo, founding date and elevation. All proceeds go towards supporting Vail's Art in Public Places program.

Cole says she wouldn't be at all surprised if Vancouverites demanded a similar sort of replica.

"Out of context, the manhole cover itself is a very beautiful thing. If you saw one on someone's wall, you would think it was pretty gorgeous."