True or False?
A little exam on water quality and other things:
1. FALSE. Our water is already plenty soft. The numbers are 40-60 milligrams total hardness per liter, or about three grains per gallon. Don’t waste your money on additional softening.
2. FALSE. Soft water is more corrosive than hard water. Hard water can cause scaling, which is often mistaken for corrosion. But very soft water will actually eat holes in metal pipe and fixtures. Water is the universal solvent. Hardness (dissolved minerals) makes it a little less aggressive toward plumbing.
3. TRUE. This is on the minds of our operators when changing chlorine gas cylinders at the plant. But, it is also the most useful disinfectant for drinking water, and is likely to be that way for a long time.
4. TRUE. UV is used in water and wastewater disinfection. The problem is, it only works once, at the treatment plant. It is still necessary to add a chemical disinfectant, such as chlorine, which will persist throughout the distribution system to combat contamination there.
5. FALSE. We only wish it were true. Pipeline breaks, degraded pipe materials, and illegal cross-connections are sources of contamination in all distribution systems.
6. TRUE. However, it is expensive to generate, and, like UV, leaves no residual disinfectant to combat potential contamination downstream. Also, ozone, like chlorine, creates undesirable byproducts.
7. FALSE. Some people are naturally sensitive to chlorine, and want it out of their water. A properly designed and maintained activated charcoal filter will remove chlorine from your tap water. Having done so, it makes possible the growth of bacteria in the filter or elsewhere. If you have a home filter, you must take care of it or you can create more problems than you started with.
8. FALSE. These little beasts have been here all along. They are intestinal parasites, living in the gut of a variety of mammals, even those who walk upright and wear clothes. They are a problem in water treatment because they are very small, live for a long time in cold water, and resist chlorine. They should not worry you, because our membrane filters remove them.
9. Read the following, then guess the answer: In May 2000, in the town of Walkerton, Ontario, seven people died and 2,300 became ill - about half the population. Some children suffered kidney damage and will be on dialysis for life. The cause was contamination of the town’s drinking water by bacteria, primarily Escherichia coli. Walkerton’s water was supplied by wells. The operators had failed to add and monitor chlorine as required by law.
10. TRUE. But it’s like our obsession with hygiene. We rid ourselves and our pets of fleas, lice and other vermin because few people would care to risk acquiring “natural immunity” to bubonic plague. Why not take the same approach to water? I believe most of us would rather not die while trying to develop immunity to hepatitis, cholera, and all the rest of the water-borne diseases.
11. FALSE, unless you work for the marketing division of a bottling company. Most bottled water is obtained from public water treatment plants. Hey, why don’t we bottle our own? You folks think of a catchy name for our product. Too bad “Evian” is already taken (it’s “Naive” spelled backwards).
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