Water Quality

If a test of your tap water produces a brown substance, is it safe to drink?  The truth is that such tests are absolutely meaningless in terms of assessing the safety of water. Unfortunately, some door-to-door salespersons have been causing unnecessary concern among Ontarians with such tests as a way of luring people into buying costly reverse osmosis treatment units.

Ontario's Chief Drinking Water Inspector, says: "If you have been approached by someone offering to test your drinking water, and you have concerns, I advise you to contact your municipality, or your local health unit - they can answer any questions you may have.  If a salesperson claims that your drinking water is unsafe or claims to be testing the safety of your drinking water, please contact the Ministry of the Environment immediately and we will follow up."

To contact the Ministry of the Environment, Conservation and Parks call the Public Information Centre's toll-free number of 1-800-565-4923 or 416-325-4000 in Toronto. If fraud is suspected, you may also contact your local police force or the Ministry of Consumer Services at 416-326-8800 in Toronto or 1-800-889-9768 toll-free.

First, they use an electric current to activate naturally occurring minerals and make the water turn brown. Then, the treatment removes the minerals from the water, making the brown substance disappear.

The test does not and cannot identify contamination that could cause illness. In Ontario, only fully accredited laboratories licensed to perform drinking water testing - not such home-based testers - are authorized to perform health-based tests on drinking water. Our stringent standards for these labs make the province's municipal tap water among the best protected in the world. The people of Ontario can have confidence that their tap water is safe to drink.

Activated carbon filter fact sheet

Water softener fact sheet

It is required by law to add a disinfectant to public drinking water. Chlorine is an effective disinfectant that kills harmful bacteria and viruses found in natural fresh water. Peterborough Utilities Commission has been using chlorine to disinfect our drinking water since 1916.

While provincial drinking water standards do not include mandatory fluoridation, many municipalities have chosen to fluoridate their water for the benefit of their customers. The City of Peterborough Bylaw 1973-1 requires us to fluoridate the City's drinking water to levels of 0.50 and 0.80 mg/L leaving the Peterborough Water Treatment Plant. At these concentrations, no ill health effects have been linked to the fluoridation of drinking water and it has noticeably improved the dental health of Peterborough residents. Peterborough's Medical Officer of Health and the Canadian Dental Association endorse the fluoridation of municipal drinking water.

When water flows from your tap, tiny bubbles from dissolved air can be released and make your tap water appear cloudy. This problem is more frequent in winter, as cold water holds air longer than warm water. Cloudiness caused by air bubbles does not pose a health concern, but for some people it is unappealing. After a few minutes, these air bubbles disappear from a standing glass, so a good solution to this problem is to keep a jug of tap water in the fridge for drinking.

Many people assume that all chemicals are health hazards but this is an unfair assumption. While some chemicals in drinking water can be unhealthy, other chemicals such as fluoride and chlorine are quite beneficial in correct amounts. The Provincial government has established safe concentrations in drinking water and frequent testing ensures that safe concentrations of all chemicals exist in your drinking water.

Routine repairs or flushing of fire hydrants and water mains can stir up sediment and cause red or brown coloured tap water. This colouring is not a health concern but can stain laundry and fixtures. Running your cold water taps for a few minutes will usually flush out any sediment in your system.

If your hot water alone appears coloured, sediment in your water heater is likely to blame. Try draining the water from the bottom of your water heater to flush out these unwanted minerals. Repeat this procedure annually to prevent further build-up of sediment.

The source of raw, untreated water for Peterborough's drinking water is the Otonabee River. The Otonabee River water is of good quality and can be described as a moderately coloured water of low turbidity. The river water temperature ranges from 0°C in winter to approximately 26°C in summer. Water is continuously being treated and tested to ensure that customers always have access to drinking water that meets or exceeds all drinking-water standards set by the Ministry of Environment.

Rainwater flows over lawns and roads into storm sewers and then directly into local waterways, carrying with it dissolved pesticides, salts, oil, and other untreated waste products. Faulty septic systems adjacent the water course and waterfowl living in the Otonabee River also contribute pollution. Fortunately, the treatment process at the Peterborough Water Treatment Plant is very effective in treating this pollution to produce safe clean drinking water.

Lead from piping in older homes can dissolve into the house's water supply if left standing for long periods of time. To minimize exposure to lead, never drink or cook with water that has been standing in your pipes for longer than six hours. Run the taps until the water feels colder to the touch and use the flushed water for household cleaning or watering plants instead. Of course removal of sources of lead, such as lead pipes or lead solder is the best way to minimize your exposure to lead in the long-term. Additionally we can provide lead testing to homeowners if they suspect they may have lead services or fixtures in their home.   

Metals from household piping and water heaters dissolve into warm water more readily than cold water. This makes water from your hot water heater more likely to contain potentially harmful contaminants. Cold water should be used for household cooking as much as possible.

The water supplied by the City of Peterborough Water Services meets or exceeds all provincial water quality standards and is perfectly safe for everyday drinking and cooking. Some people who are sensitive to tastes or odours may use bottled water or in-home filters for drinking. This is a personal choice.

Chlorine is a very effective disinfectant that has been used successfully to treat Peterborough's drinking water for many years. Chlorine purifies water by killing harmful bacteria and other germs that pose health threats, but sometimes it can react with non-toxic, organic substances in the water to produce disinfection by-products (DBPs). Trihalomethanes (THMs) are regulated DBPs that can be formed during the disinfection process. As a result, THM's are tested quarterly both at the treatment plant and out in the distribution system to ensure that concentrations are at acceptable levels as established by the Ministry of the Environment.

White or tan particles in tap water usually come from the inside of your pipes, water heater or water softener. These particles can be a combination of calcium carbonate and magnesium carbonate and are often referred to as pipe scale. Calcium and magnesium carbonates are naturally occurring minerals and are found in varying concentrations in most waters around the world. These minerals are not a health threat; in fact, they are beneficial to human health. The amount of these minerals in the water determine the hardness of the water; higher mineral concentrations make the water harder. Over time, these minerals can deposit on the inside of your pipes and then begin to flake off. If you add a water softener to your plumbing system, the softer water can begin to re-dissolve the minerals from the pipes and pieces may begin to break loose. These are all common causes of pipe scale in the water and account for most customer complaints about white or tan particles in the water. Although pipe scale is not a health hazard, it can be a nuisance by clogging inlet screens to washing machines, showerheads and faucet aerators (the screen that screws on to the end of the water faucet).

In response to the W5 television program episode that aired over the weekend of March 26, 2023 about asbestos cement water mains, we would like to share some technical resources below for reference on the subject.

Health Canada and the World Health Organization have concluded that there is no consistent, convincing evidence that asbestos ingested through water is harmful to your health. If you drink water containing asbestos fibres, you eliminate the fibres, mostly through feces. For this reason, Health Canada has not established drinking water guidelines for asbestos.

We currently have around 4.7 km of AC pipe in Peterborough, which is less than 1% of the total length of water mains

Additional information on this subject can be found at the links below:

• Guideline for Canadian Drinking Water Quality: Technical Document - Asbestos
• Canadian Water and Wastewater Associate Speaker Notes on Asbestos