The province is looking into new building rules that could allow greater use of reclaimed water.
A provincial working group is working on revisions to Alberta's building code, according to Alberta Municipal Affairs spokesperson Alf Durnie. In addition to changes that could raise energy efficiency standards, the group is also looking at how to regulate reclaimed or greywater — rainwater, stormwater, and wastewater that's partially treated for re-use.
Reclaimed water is one way Alberta can use water more efficiently under its Water for Life Strategy, said Durnie, the province's chief administrator/inspector of private sewer systems. By using water from your kitchen sink to water your lawn, Albertans could reduce the demand for fresh water and drain less of it from lakes and rivers.
But provincial law forbids many uses of reclaimed water — you can't use treated sewage to water lawns or gardens, for example. "Wastewater contains pathogens," Durnie said, and the province needs to be sure it gets treated enough to be safe for use. Residents might also be turned off by its look or smell, or ripped off by a shoddy rainwater collection system.
His group plans to release new guidelines to building residential rainwater systems in the fall, Durnie said, followed shortly by commercial guidelines. The group should have a draft framework for wastewater reuse by next spring.
It's high time the province took these steps, said Jim Hole of Hole's Greenhouses — he wants to use reclaimed water in his new greenhouse but can't until the province figures out its regulations. "The sooner we have a definition of greywater, the better off we are."
Light use, big savings
Albertans need maybe five litres of drinking water a day, said Jay White, a water quality biologist with Aquality Environmental Consulting, but use hundreds more to wash dishes and flush toilets. "Do we really need to be using world-class treated water to water our lawns?"
It's a waste he said could be avoided by using less-treated sources of water. Take rain, for example. Many European homes channel rain from their roofs into cisterns for later use. Those homes have two water systems, White said — one for rainwater, one for drinking water. By storing rainwater and using it during dry periods to flush toilets, those homeowners reduce demand on stressed rivers and get free water.
There aren't many buildings in Alberta that have such a system, Durnie said, but many have rain barrels. The new Hole's greenhouse will have a cistern to collect rainwater for its plants, according to Hole.
Many industrial processes can use treated wastewater in their plants, White said. Suncor's Edmonton refinery uses water from the Gold Bar treatment plant, for example, instead of taking about 5.5 million litres of water a day from the North Saskatchewan River. Most homes wouldn't have the resources to safely use wastewater, but big communities or buildings with treatment wetlands could pull it off.
Hole hoped new regulations would let his greenhouse have three water systems: tap water for drinking, rainwater for plants, and greywater for lawns. "You'd offset a huge proportion of the [water] demand with that."
Greywater has great potential, White said, but the province has to make it legal to use. His home used about 16,000 litres of water last month, almost all of which he said he could have replaced with greywater. "It's a colossal waste."
