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Liquid assets
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Straight up facts about tap water and your health
By Ian Douglas, Water Quality Engineer
 Every day, most Canadians turn on the tap and enjoy a glass of water. But for many people in the developing world — and parts of Canada, as the recent tragic outbreak of e. coli. bacteria in Walkerton, Ontario, demonstrated — safe drinking water is not to be taken for granted. The 1993 Milwaukee outbreak of waterborne Cryptosporidium, which made more than 400,000 people sick and killed 100, also demonstrated that public health relies on safe drinking water. How could something as simple as tap water undermine our enviable standard of living?
Since ancient times, human civilization has revolved around its water supply. Egyptians used alum and sweet almonds to clarify drinking water before consumption, and the Romans were no slouches in water supply engineering, boasting sophisticated plumbing far before other civilizations. Our Canadian population has invariably settled around plentiful sources of fresh water: water for transportation, for energy, for industry, for beauty, for washing, and of course for drinking.
Although we live on a blue planet, 99 per cent of the water is non-potable, either as ocean salt-water, or frozen at the polar ice caps. In Canada, we have access to 25 per cent of the world’s fresh water supply. With only 1 per cent of the world’s population, Canada is blessed with fresh water supplies well beyond our needs.
Nevertheless, our grandparents knew the value of safe drinking water. Chances are they knew someone who died from typhoid fever, cholera, dysentery, or some other waterborne disease at the turn of the century. In fact, chlorination of drinking water supplies has been cited as the 20th century’s top achievement in advancing public health. First applied to a water supply in Ottawa in 1911 following a severe typhoid epidemic, chlorine has been hailed as both saviour and evil temptress.
Remember Grade 5 biology class? Our bodies are composed of roughly two-thirds water, one-third other stuff. That likens us to a bunch of water balloons blobbing around, each with a unique collection of water and bones. Not very poetic on a philosophical scale, but evidence perhaps that we truly are what we drink. If this is so, then how safe is the water that we swallow each day?
Drinking water is not sterile, nor does it need to be. Our bodies are designed to handle ambient background levels of bacteria and other trace substances. What need to be removed are pathogenic viruses, bacteria and any harmful chemical substances. Fortunately, most are removed through conventional water treatment processes, the level of treatment depending upon the quality of the source water. Most treatment plants use a “multiple barrier” approach that removes contaminants through several stages of treatment, removing about 99.99 per cent of particles and micro-organisms from the source water.
The Canadian Water & Wastewater Association maintains that water supplied across the country is of high quality and among the safest in the world. There are 104 substances regulated in the Canadian Guidelines for Drinking Water Quality produced by Health Canada (www.hc-sc.gc.ca). Each standard is thoroughly researched by epidemiologists, health officials and engineers to set a limit that is safe and protective of public health.
Talk to your local water supplier and request the details about your water quality. Compare your local standards with the guidelines for safe drinking water quality, especially the 84 health-related standards. Most municipal water supplies in Canada are well within the guidelines.
What about bottled water? Whether derived from a mountain stream or an iceberg, bottled water is definitely a health trend. Most bottled waters in Canada are safe to drink, although a recent Health Canada study found 30 per cent of commercial bottled waters do not meet health standards. Instead, water bottlers are governed by food and beverage regulations, which for water mostly deal with packaging guidelines.
Most bottled waters taste good, but cost approximately 10,000 times more than tap water, which must comply with rigorous drinking water standards. Put another way, it will cost you one cent to fill a bottle 60 times with tap water. A reality check for sure, but most consumers of bottled water simply buy into the “purity” myth reflected by the pretty labels.
There’s also the convenience of carrying a bottle wherever you go. It’s a recent cultural phenomenon to see people carrying their bottle of water with them like a lifeline — hiking, shopping downtown, at the work station, or out on the soccer field. Water’s popularity is probably triggered by the health-conscious push to drink eight glasses of water a day, which is a good thing. But when I was a kid playing Frisbee on a hot summer day, it was just the splash of the garden hose.
What about treating tap water at home? There are dozens of devices — from carbon filtered pitchers to faucet attachments — that are capable of removing undesirable substances, if they are present in the tap water in the first place. However, for most municipal water supplies, further treatment is not necessary and won’t improve the healthiness of your tap water.
That said, most substances that are harmful to your health cannot be detected by human sensory perception of sight, taste or smell. Instead, modern analytical laboratories routinely measure thousands of substances at trace quantities. Again, talk to your local water supplier and request the details about your water quality. If your water has some esthetic problems such as taste, odour, iron, sulphur, or hardness, there are some effective filters for removing these.
The best advice is simple: first decide what substance you want to remove and why, then search the market carefully for the product to match. Talk to a professional at your local water supply, investigate consumer reports, and look for a National Sanitation Foundation (NSF) rating on the product for quality assurance. Lastly, follow manufacturers’ instructions for operating. Some devices can actually make water quality worse or unsafe if not used correctly.
If you live on a private well, understand that your water quality and health is solely your responsibility. Most groundwater wells provide a safe water supply, but should be monitored for contamination. Have your water tested every six months for bacteria, preferably in spring and fall when the water table is changing. Your local health department will test Total Coliform bacteria and e. coli. at no cost. If you suspect possible contamination from pesticides, fertilizer, heavy metals, petroleum, or solvents, then contact a private lab to conduct a more thorough drinking water analysis. It will cost you approximately $100, but will help protect you and your family’s health.
A taste test
If you don’t like the taste or smell of your tap water, try this experiment at home. Run the cold water for a few minutes to obtain a fresh sample. Fill a jug and refrigerate overnight. In a blindfold test, compare the taste of this water to your favourite bottled water or filtered water. You might find that simply cooling the water and letting it breathe overnight provides a palatable glass of water at a fraction of the cost.
Ian Douglas, B. Sc., B.E.Sc., P. Eng., is responsible for the quality of the drinking water in the Region of Ottawa-Carleton.
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