Terry Halifax
Northern News Services

Yellowknife (Apr 24/00) - Northerners are blessed with some of the largest supplies of fresh water in the world. Our massive lakes and river systems account for about nine per cent of the world's fresh water.

Each spring our creeks and rivers rush with the melt of the winter's ice and snow, pushing the water at a force about five times as fast as the normal river flow. The raging waterways become muddied with the sediments of centuries gone by.

Along with the fine silt, the waters are teeming with a winter's worth of caribou droppings, carcasses, organic material, bacteria and parasites pulled in from the river banks and melting ice surfaces.

Terry Brookes, an engineer for Municipal and Community Affairs (MACA) said community-based water systems, whether trucked or piped, need treatment year-round but especially in the spring, to make sure these floating contaminants don't make it to our water glass.

"We've come a long way in the delivery of water up here, but there's always room for improvement," he said. "Our waters are relatively pristine, and the problems we have are with spring thaws.

"The water treatment people will be a little more cognisant of the problem and add more chlorine," he said. "A good operator will know if there is less and less residual chlorine as it gets used up."

The parasite -- Giardia Lamplia -- that causes so called "beaver fever", is particularly resilient and can be present in untreated water, especially in the spring.

"It's one we associate with people out on the land at a nice pristine lake and they're drinking from it, not noticing the beaver pond over there..." Brookes said. "Not that all beavers have them. Some do and they can stick around for a while."

Even boiling water may not kill the Giardia. "The stomach is a very acidic environment and these things survive -- they've been evolving for thousands of years.

"It's a resistant type of bug. It's not a bacteria, it's not a virus, it's a waterborne parasite. It could be muskrats or beavers. It comes from rodents and it's there and needs to be treated."

Water in the NWT is filtered and then treated with powdered chlorine. Some municipalities use ozone, steam or ultraviolet light to treat water, but Brookes said chlorine is still the most practical solution for the North.

Health and social services environmental health consultant Duane Fleming says Giardia is not a big problem in the North, but people drinking untreated water should boil it for at least five minutes before drinking.

"If you're getting your water from the municipal source, you won't have a problem," Fleming said. "It's rarely associated with a public water system.

"Chlorine has no effect on it, the water has to be filtered," he said.

Although thousands of caribou migrate along our frozen river systems, Fleming said there is no Cryptosporidium, a water-borne parasite associated with animal feces.

These illnesses can cause vomiting, cramps and diarrhoea and can last for as long as a month.

According to health and social services records there have been about 60 confirmed case of Giardiasis and only one case of Cryptosporidosis in the NWT over the past 10 years.

"Certainly some animal feces get into the water, but again, if you're drinking chlorinated water, that shouldn't be a problem," he said.

Community research

Dr. John Morse a doctor of internal medicine at Stanton Hospital in Yellowknife, hopes to undertake a study of water in the North to search for a bacteria now established as the primary cause of ulcers and may also be linked to some forms of cancer.

Helicobacter Pylori, a bacteria that is found only where humans exist, but as of yet, no one has been able to determine where the bacteria originates.

"We know it comes from man -- it's not from nature, you only find it where there are people," Morse said.

Morse suspected the bacteria comes from domestic water sources and feels the North would be a suitable environment to conduct a study because of the isolated communities.

"We're finding it a lot, but not necessarily more than you'd find in Alberta or B.C. or anywhere else -- we just think because of our geography, that we might have a good opportunity to study a relatively cohesive and isolated community," Morse said.

If the study goes ahead, Morse said they will pick one community and conduct an extensive study of the water system.

"It's going to be a fairly big undertaking in terms of manpower and dollars, so we want to make sure it's scientifically sound," he said.