There are many coliform bateria in our water, but many in small numbers are no threat.

Canadians used to be complacent about the purity of their drinking water. Then came the wake-up call at Walkerton. Until recently, Walkerton was a tranquil southwestern Ontario town, a friendly, vibrant tourism hotbed known for its quaint shops, nature trails, and canoe trips along a serpentine Saugeen River abundant with trout, bass, and salmon.

But today, in the daunting aftermath of a water-borne E. coli bacteria outbreak that killed six people and made nearly 2,000 sick, Walkerton has become eerily synonymous with an issue few would have thought possible in a country like Canada.

Of course, Canadians are well aware water contamination is a too-common occurrence in developing countries where water supplies are often scarce. Few Canadians, whose country boasts the most ample supply of fresh water in the world, would be surprised to learn 50 percent of the population in such nations suffer from afflictions related to contaminated water or food, according to UN University's International Network on Water, Environment, and Health.

But the Walkerton crisis has brought all that home. Suddenly, Canadians who never gave a second thought to the ready supply of water pouring from their taps are asking serious questions. Where does our water come from? How safe is it? What's being done to make sure it stays safe?

"Until the Walkerton tragedy I would have ranked the quality of Canada's drinking water among the best in the world," says Robert Gillham, a University of Waterloo researcher and hydrogeologist. "Most Canadians consider safe and ample drinking water their birthright, so Walkerton was very sobering. And there's sufficient evidence now to think that maybe our water quality isn't as good as we once thought it was."

Not that Canada's water is unsafe. Experts say the water quality is still comparable with that of any developed country and is vastly superior to that of developing nations.

Still, researchers have long been wary of increasing risks of water contamination in a country where preservation of natural resources has traditionally remained a low priority. They point to proliferation of fertilizers and industrial chemicals, farm run-off, septic tanks, and increased demand resulting from a burgeoning and rather wasteful population.

Back in 1992, mounting concerns about risk of groundwater contamination from various sources, as well as growing reliance on lower-quality surface water due to rapid population growth in larger communities, prompted the Natural Sciences and Engineering Research Council (NSERC) to establish a multi-million-dollar research chair on water treatment. Waterloo civil engineering professor Peter Huck, a renowned expert on water treatment who researches problems of contamination from uranium mining effluents, has served as chairholder since its inception.

Around that time a report by a task force of scientists and engineers appointed by the Canadian Geoscience Council warned about increasing risks of water contamination due to a scarcity of research and inability to recognize and solve groundwater problems before they reach dire and expensive proportions.

And just this summer, an Ontario environment ministry inspection blitz of 240 water treatment facilities across the province found deficiencies in almost two-thirds of them. Although there were no claims that water flowing from these plants was unsafe, the inspectors nevertheless found problems ranging from inadequate monitoring to insufficient chlorination. In 72 cases, field orders were issued for immediate remedial action.

"The problem is that we don't know if we actually have a worsening situation," Gillham says. "There are many coliform bacteria in our water but many in small numbers are no threat. We have just gone through a very traumatic experience in Walkerton. And now we've become very concerned about every bacterium that shows up. But, on average, are things getting worse? Or is Walkerton an isolated incident?"

That, for government officials, researchers and, of course, consumers, is the burning question.

A resource historically taken for granted in Canada is undergoing unprecedented scrutiny these days. Already, the Ontario government has come out with stringent new measures to bolster monitoring, testing, and treatment of water and ensure better and more timely reporting of problems that arise.

Which is lauded by people like Huck, who say Canada's regulatory system has always lagged well behind that of the United States.

"The US has a much more rigorous approach to regulating the levels of treatment and monitoring than we do," Huck says. "Some of us have felt it would be very beneficial if we could come close to what the US is doing and there's a sense that this may now be happening."

About 25 percent of Canada's water flows from the ground, from wells filled by nature-fed-and-replenished sand and gravel aquifers. Central Canada uses about 40 percent of that groundwater. The rest of our water comes from surface sources such as lakes, rivers, and streams.

Whatever the source, the water works its way through municipally run distribution systems and facilities where the water is treated with chlorine and sometimes ozone to kill bacteria and chemicals. Ideally, the water is regularly tested and monitored by qualified technicians to ensure it meets government-set safety guidelines.

But a lack of financial resources, particularly in smaller, rural areas, has sometimes created significant shortfalls in that regard. In many of these communities, Huck points out, less-than-qualified technicians are forced to juggle responsibilities that include testing and monitoring of water. Often, they lack training and expertise to respond appropriately when problems or concerns arise.

Susan Andrews, a Waterloo civil engineering professor who has conducted extensive research in the area of water treatment, believes the economic realities faced by rural communities remain a major concern when it comes to the provision of universally safe drinking water in Canada. "Larger cities have the resources to install a multi-barrier approach," she explains.

"Which means that if one thing should fail, there is a backup system or procedure available. Smaller municipalities often lack the resources for that."

Nevertheless, Andrews says there are few municipalities in Canada where water quality is 'out of whack' with government-set safety guidelines. Federal guidelines tend to state true maximum acceptable level of concentration (MAC), while the provinces, if they are so inclined, can specify somewhat lower levels. Municipalities can do the same, Andrews says, but rarely do because they generally lack financial resources to provide additional monitoring that would be required.

Reprinted with permission from the University of Waterloo Magazine, Fall 2000.