FAQ's - Water Quality
- Why does the water sometimes appear dirty and discolored, or have a sulphur odour?
- How can Iron, Manganese, and objectionable odours be managed?
- What about in-home water treatment systems?
- What is water hardness?
- What is a coliform?
- How often is the water tested and what is it tested for?
Answer: Iron and manganese are often found in a dissolved state in groundwater. Generally, the water appears clear when first drawn. Upon exposure to air, or after the addition of oxidants (such as chlorine bleach or ozone), this ferrous iron is oxidized ("rusted") to the ferric state to form insoluble particles. The water then looks orange or yellow, or in the case with manganese, brown or black. This can happen in toilet flush tanks and in the washing machine or dishwasher. Sulphur odours are caused from a small amount of hydrogen sulphide gas present in the groundwater that becomes more apparent in the warmer summer months. As little as 0.5 parts per million hydrogen sulphide is detectable by taste in drinking water. Occasionally an odour is present in the hot water only. This condition is usually caused by a chemical reaction which takes place within the water heater. When hot water containing sulphate salts comes into contact with the magnesium sacrificial anode, which is a normal part of most water heaters, a reaction occurs, converting some of the sulphate to hydrogen sulphide. Since the magnesium anode rod is removable, in many cases, removal of the rod is a remedy for the problem. Many people remove the rod entirely. Remember though, the anode is used in a water heater to reduce corrosion in the heater tank and its removal may invalidate the warranty.
Answer: RDN Water Services removes settled deposits of iron and manganese and pockets of "stale" water by regularly flushing water lines and reservoirs. RDN Water Services continues to explore and test other treatment options. Homeowners can control iron and manganese by regularly flushing their water lines and hot water tanks and twice annually opening all inside and outside taps to remove sediments and maximize water flow. Letting a tap run first thing in the morning will clear any sediment from the service line. Avoid using bleach when doing the laundry as it compounds the problem of iron staining by intensifying precipitation and oxidation. You can use a non-chlorinated whitener, such as OxiClean, to help remove existing stains from kitchen and bathroom fixtures and clothing, and keep stains away when added to your laundry along with your regular laundry soap.
Answer: Methods such as ion exchange, oxidizing filters and reverse osmosis can be used to treat problems with iron and manganese, however, their effectiveness varies and the costs to install and maintain systems can be high. The National Sanitation Foundation certifies water treatment products for specified purposes. RDN Water Services recommends that homeowners check the National Sanitation Foundation's Website at www.nsf.org before purchasing a unit.
Answer: The hardness of water is generally due to the presence of calcium and magnesium in the water. Hardness is reported in terms of calcium carbonate and in units of milligrams per litre (mg/L). Waters with values exceeding 120 mg/L are considered hard, while values below 60 mg/L are considered soft. Harder water has the effect of reducing the toxicity of some metals (i.e., copper, lead, zinc, etc.). Soft water may have corrosive effect on metal plumbing, while hard water may result in scale deposits in the pipes. If the water has a hardness of greater than 500 mg/L, then it is normally unacceptable for most domestic purposes and must be treated.
Answer: A group of closely related bacteria. Measuring coliforms provides an estimate of the degree of fecal contamination from human and animal wastes. Total coliforms include fecal coliforms, common to the intestinal tract of both humans and warm-blooded animals, and non-fecal coliforms that are naturally present in soils and on vegetation. While the presence of coliform bacteria does not necessarily cause disease, it may indicate the presence of pathogens that cause human illness.
Answer: RDN Water Services complies with Drinking Water Protection Regulations (2005), as do other municipal and private water systems in the province. The Regulation has sections dealing with water potability, the collection of samples and sets criteria that sample tests must meet.
The Environmental Health Officer designates the locations for the weekly collection of samples from RDN water systems. These samples are tested by both RDN Water Services staff at its lab and at a private lab chosen by the Health Authority. Water samples are tested for total and fecal coliform. The presence of fecal coliform indicate that the water may contain bacteria harmful to human health and would trigger an immediate "boil water advisory" for water system users.
In addition to weekly tests provided to the Health Authority, the RDN Water Services conducts annual potability tests on water from its systems. These tests measure chemical and physical properties such as colour and the presence of metals or minerals. The results of these potability tests are compared to the Guidelines for Canadian Water Guidelines. Water from the RDN's Water Service Area wells continues to meet the Guidelines except for periodic exceedances of certain aesthetic objectives such as iron and manganese.