In the major local revolution over how best to get rid of different kinds of garbage, one small piece has flown under the radar: garburators.
In many circles, the gadgets, reminiscent of the 1960s era of suburban house-building, get a thumbs down.
The David Suzuki Foundation's Lindsay Coulter pooh-poohs them, saying it's better to compost. Many cities in Canada and the United States have banned them outright, saying they put stuff in the sewage system that clogs it or is expensive to treat.
But some cities are reversing their bans and looking at new ways of working with food waste from garburators.
And Metro Vancouver is holding off on any official policy about in-sink garbage disposals, even though its bureaucrats and politicians have taken strong stands on everything else, with a ban on food scraps in landfills coming into place in 2015.
But its go-slow approach on garburators is due partly to the fact that it looks as though people are voluntarily using them less.
"We're not currently looking for a requirement for a ban and we might not need a policy one way or the other," said Fred Nenninger, Metro Vancouver's director of wastewater-treatment-plant upgrades. "With efforts at water conservation and green bins [for food scraps], the rate of use is slowing down quite a bit. Once you have a green bin, it's easier to put stuff there."
The amount of food waste that ended up in the sewage system, which is where garburated food scraps go, used to increase in line with population increases. But that's slowed down, said Mr. Nenninger.
Currently, about 25,000 tonnes of food now end up in the region's two treatment plants, 7 per cent of the total volume. Estimates indicate about 50 per cent of homes have garburators.
However, some cities elsewhere are looking at how to do more with the food scraps in their recycling system.
"The trend in the wastewater area now is to look at it as more of a resource than waste," said Kendall Christiansen, a consultant with the U.S. InSinkErator empire. "This is a whole new field in food waste."
Wastewater-treatment plants are being designed to do more to capture biogas and turn the solids filtered out of sewage into fertilizer. The region's new, $750-million Lions Gate treatment plant will have some of those capabilities.
Mr. Christiansen, who follows Metro Vancouver's policy stands closely and will be at the region's annual Zero Waste Conference next week, said he tries to make sure that bureaucrats keep open minds about the appliances.
Vancouver is an ideal candidate for garburators because of its already dense pockets of high-rise residential areas, with plans for more.
"Vancouver's a very important market for InSinkErator," he said.
The garburator industry currently has demonstration projects going on in five U.S. cities it has partnered with, including Philadelphia and Tacoma, Wash.
"These are all cities that have said to us, 'We don't want to put another truck on the street to collect food scraps,'" Mr. Christiansen, a former recycling manager with the City of New York, said. He said the industry is also working on options for commercial operations that would entail placing a vat on-site. It would contain ground-up food waste and water that would be stored as a kind of slurry that could then be pumped out.
Metro Vancouver officials aren't quite as enthusiastic about the new ideas.
Mr. Nenninger and Darrell Mussatto, the City of North Vancouver mayor who is chair of Metro Vancouver's utilities commission, both say that the best thing for residents and businesses to do is put food scraps into green bins.
Mr. Nenninger said it costs about $1,000 a tonne to process food scraps that end up in the sewage system, compared to $100 a tonne when they go into a bin. (The York region of Ontario, which looked at whether to ban garburators and didn't, estimated the costs much differently, saying it was $236 to process food scraps in sewage, versus about $178 in green bins.)
However, he acknowledged that some of the region's older buildings may never be able to switch over to a green-bin system because they don't have the room.
"If they can't do green bins, maybe the garburator is an option."