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Drinking water - Frequently asked questions

Answers to the most commonly asked questions about drinking water. If you have a question that is not addressed, please call 3-1-1.

Common questions about water quality

Taste and odour

  • “Earthy” or “musty” odour: Ottawa's water system draws from the Ottawa River, which has a natural, slightly "earthy” or “musty" odour. This odour is caused by trace levels of natural organic substances produced by plants and algae in the river. The water purification process removes almost all of the odour present in the river water. Some sensitive consumers may still notice an odour, especially when tap water is warmed up (e.g. showering). The odour is not a health concern.
  • “Sulphur” or “septic” odour from your tap: If you notice a "septic” or "sulphur" odour when using the bathroom and kitchen faucets, it is usually caused by decaying hair, dirt and debris that is caught in the drain. It is not coming from your tap water. To check this, fill a glass with cold water and take it immediately to another room in the house. If this water is odourless, the odour is coming from your drain. To correct the problem, the drain must be cleaned physically or with the use of a chemical drain cleaning product. Alternatively, you can pour a small amount of baking soda, followed by vinegar down the drain. Wait a few minutes and then run your cold water tap for one minute.

My water looks cloudy

At times during the year, you may find that your tap water appears cloudy. This is not a health concern. The cloudy water you are experiencing is due to air bubbles that are trapped in the tap water. As the water warms up slightly in your household plumbing and pressure is reduced through your tap fixture, dissolved air will be released resulting in the cloudy white appearance when filling a glass which should disappear within a few minutes. To confirm this, pour some cold water into a glass and observe. You should notice the air bubbles gradually disappear from the bottom of the glass upwards within 1 to 2 minutes. If the cloudiness persists, call 3-1-1 to arrange for water quality testing.  

Rusty/discoloured water

If the water in your cold water tap or toilet tank is rusty, yellow, or discoloured, this could be a result of sediment coming from the water main. This often occurs when water main construction or fire hydrant maintenance is being conducted in your area. Sudden changes in flow can disturb rusty or iron sediments within older water main pipes. The red/yellow discoloured water is caused by the presence of iron, and while it is not aesthetically pleasing, it does not pose a health concern.

Do I need to filter or boil my water?

You do not need to filter or boil your tap water. Be aware of door-to-door salesmen or imposters making false claims about the City’s tap water being unsafe. Ottawa’s tap water is tested more than 100,000 times a year at 65 different locations. Since 2009, Ottawa-owned water purification facilities have received only perfect scores in annual inspections performed by Ontario’s Ministry of the Environment and Climate Change. If you require additional information or would like to have your tap water tested, please contact 3-1-1 (TTY 613-580-2401). 

Residents serviced by a communal or private well may consider purchasing an in-home treatment system for aesthetic purposes such as taste or odour. For more information, please email info-water@ottawa.ca or consult the following Health Canada resources before purchasing an in-home water system:

Is there lead in Ottawa's drinking water supply?

Drinking water supplied by the City is lead-free. However, trace amounts of lead can dissolve into drinking water during contact with plumbing materials in the home, such as lead pipes, brass fixtures, and lead solder. This may have an effect on the safety of tap water.

In most cases, lead concentrations in Ottawa’s tap water are well below the drinking water standard of 10 ppb (parts per billion), as established by Health Canada and the province of Ontario. Typical concentrations are as follows:

0 ppb leaving Ottawa’s water treatment plants0 ppb for tap water in the majority of Ottawa homes (85%)1-5 ppb in most homes with lead service pipes. In some homes, the lead concentration can be higher than 10 ppb, usually due to the length of the water service pipe connected to the home.

For information on having your lead service line replaced refer to the Lead Pipe Replacement Program.

Particles or sediment in your tap water

Occasionally, particles might be observed in your tap water. There are a few common situations that can lead to particles:

  • White/brown particles: If the particles are white and appear to have a slight brown appearance on one side, it might be a piece of ceramic from the liner of your hot water tank. To check this, the particle should be able to be crushed with a spoon and should fizz when vinegar is added. Contact your hot water tank supplier and have it inspected if you find ceramic particles in your water.
  • Sand or sediment: If the particles appear to be sandy and are observed in the storage tank at the back of your toilet, it is most likely sediment that was disturbed in the water main. Hydrant flushing will generally clear any sediment from the water mains in your area. If the issues persists, contact 3-1-1 to have the hydrant flushed again.
  • Black particles: Black particles can sometimes be small pieces of rubber from a deteriorating gasket or rubber washer in your tap fixture. In some cases, black particles can be caused by the presence of high levels of manganese in a groundwater well. In this case, contact 3-1-1.
  • Reddish/brown: If you observe tiny brown spheres in your tap water, it might be resin beads from a water softener or filtration system. These beads look almost translucent and their presence indicates your water softener needs to be inspected or replaced.

What is the pink stuff in my bathroom?

Many customers report a persistent pink stain in their bathroom, usually on moist surfaces such as tile grout, showerheads, sink drains, or bathtub surfaces. This is usually caused by an airborne bacterium called Serratia marcescens commonly found in air, dust, and soil. These bacteria thrive on moisture, dust, and phosphates and are widely distributed especially in areas under construction or near farms. The bacteria, produces a pinkish or orange film on surfaces that are regularly moist, such as bathroom surfaces. The best solution to keep these surfaces free from the bacterial film is routine cleaning using a disinfectant such as Javex or a bleach-based cleanser. Installing a bathroom fan will also help to minimize the moist environment in bathrooms.

Is there fluoride in Ottawa’s drinking water?

The City of Ottawa adds fluoride to the drinking water. The target level of 0.70 mg/L (ppm) of fluoride in the drinking water is maintained in accordance with a recent study entitled “Findings and Recommendations of the fluoride Expert Panel to Health Canada”. The target level of 0.70 mg/L is within the 0.50 – 0.80 mg/L concentration range for fluoride suggested by the Ontario Ministry of the Environment and Health Canada, where adding fluoride to drinking water is practiced.

Fluoride is not added to the water from the five communal well systems (Carp, Munster, Kings Park, Shadow Ridge and Vars) owned and operated by the City. However, drinking water from these systems may contain naturally occurring fluoride in the range of 0.10 mg/L to 0.70 mg/L.

Water system       Fluoride concentration
Ottawa central water supply                    0.70 mg/L
Carp well system                      0.55 mg/L
Kings Park (Richmond) well system 0.40 mg/L
Munster well system                              0.65 mg/L
Shadow Ridge (Greely) well system           0.05 mg/L
Vars well system                                          0.15 mg/L

Why does the City use chloramine and chlorine?

As part of its ongoing commitment to maintain and improve drinking water quality, the City of Ottawa implemented a new way of disinfecting drinking water in July 1992. Chloramine (a combination of chlorine and ammonia) is now added to the water before it travels through the distribution system. Chloramine is an effective and long-lasting disinfecting agent that is safe for drinking, cooking and bathing.

Chlorine is used in the five communal well systems’ (Carp, Munster, Kings Park, Shadow Ridge, & Vars) water supply. It is added to provide disinfection during treatment and to maintain water quality throughout the distribution system.

Is Ottawa’s drinking water hard or soft?

Water hardness is determined by the amount of calcium and magnesium that is dissolved in water. Ottawa’s water supply is considered very soft, resulting from the natural softness of our source water (Ottawa River). Hard water does not pose any health concerns, however it can lead to scale deposits on hot surfaces such as kettles and hot water tanks.

 Ottawa’s central drinking water supply is about 30 mg/L (ppm) of total hardness which is considered very soft. On the other hand, ground water wells such as the communal well systems often have high levels of hardness due to presence of natural calcium and magnesium minerals. Levels of hardness are shown below for comparison.

Water system       Hard/soft
Ottawa central water supply                    30 mg/L  (very soft)
Carp well system                      225 mg/L (moderately hard)
Kings Park (Richmond) well system 270 mg/L (moderately hard)
Munster well system                              185 mg/L (moderately hard)
Shadow Ridge (Greely) well system           350 mg/L (quite hard)
Vars well system                                          100 mg/L (low hardness)

Chloramine in drinking water

As part of its ongoing commitment to maintain and improve drinking water quality, the City of Ottawa implemented a new way of disinfecting drinking water in July, 1992. Chloramine, a combination of chlorine and ammonia, is now added to the water before it travels through the distribution system. Chloramine is an effective and long-lasting disinfecting agent that is safe for drinking, cooking and bathing.

Why does the City use chloramine?

Here's why the City switched from using chlorine to chloramine:

  • Chloramine is a more stable and persistent disinfectant. It preserves the quality of the purified water as it travels through Ottawa's large and expanding water distribution system;
  • Chloramine helps to reduce disinfection by-products such as trihalomethanes (THMs) in the water;
  • Chloramine reduces the taste and odour of chlorine in tap water.

Is chloramine safe?

Yes. Chloramine has been used safely in Canada and the United States for years. Many water utilities are in the process of switching to chloramine because of its benefits.

The Ontario Ministry of Environment (MOE) and Health Canada recognize chloramine as a safe disinfectant that reduces the formation of disinfection by-products and disease-causing organisms. Chloraminated water is safe for drinking and all water uses.

Note: Kidney dialysis patients must take special care with chloraminated water. 

What are trihalomethanes (THMs)?

THMs are chemical compounds that form when chlorine mixes with naturally occurring organic material in water. These compounds are suspected carcinogens. The MOE and Health Canada have set a standard of 100 parts per billion (ppb)* as the safe maximum level of THMs in drinking water, based on a lifetime of consumption.

*Note: one ppb is comparable to one second in 32 years, or 1¢ in $10,000,000.

Does the City’s water meet the standard for THMs in drinking water?

Yes. The use of chloramine instead of chlorine as a purification agent has reduced the average yearly concentration of THMs to 40 ppb, well below the 100 ppb limit.

Does using chloramine increase the cost of water?

No. The cost of using chloramine is about the same as using chlorine.

Do home water softeners remove chloramine?

Most water softeners are not designed to remove chloramine.

Does bottled water have chloramine?

Normally it does not. Bottled water could contain chloramine if the company uses water supplied by the City as its water source.

Does the pH of water remain the same with chloramine?

Yes, the pH remains the same. The normal pH range for the City's water is 8.4 to 8.8.

What does chloraminated water taste like?

Chloramine itself is colourless, tasteless and odourless. In comparison to chlorinated water, chloraminated water does not have a strong chlorine taste.

If chloramine is such an effective disinfectant, why is it not used in every community?

While the public often considers all drinking water to be the same, the local raw water and water distribution conditions determine the best option for each particular community. Both chlorine and chloramine have their own advantages and disadvantages. Given sufficient contact time, chloramine is as effective as chlorine in destroying bacteria. While chlorine works more quickly, it does not last as long in the water as chloramine.

Is chloramine safe for swimming pools?

Yes. Your pool still requires a free-chlorine residual to delay algae and bacterial growth. Test kits measure free-chlorine residuals and can be used with confidence. Contact your local pool supply store for details.

Is it okay to use chloraminated water on plants, vegetables and fruit trees?

Yes. The small amount of chloramine present in the water should not affect plants of any type. Beneficial bacteria are generally protected by the soil in which they live.

What is Ottawa doing to further improve the quality of drinking water?

The City is carrying out a number of process studies and experiments to optimize our existing treatment process. New methods of water purification such as ozone and bio-filtration are being tested at the City's Pilot Plant Research Facility, in partnership with several universities. These initiatives are underway to continually improve water quality and to better serve the needs of our expanding community.

Chlorine in drinking water

Why is chlorine used to disinfect drinking water?

Chlorine has been used since 1911 to disinfect drinking water supplies around the world. It is a strong oxidant that kills bacteria and viruses that are harmful to human health.

What are trihalomethanes (THMs) and where do they come from?

THMs are formed when chlorine reacts with naturally occurring organic material in water. The organic material comes from decaying vegetation. When chlorine is used in the purification of drinking water, THMs are an inevitable by-product. THMs are suspected carcinogens.

What are the major factors that influence THM formation?

There are three major factors which contribute to the formation of THMs:

Chlorine Dose:

Chlorine is used in the water purification process to kill bacteria. Bacterial growth is at its highest in the summer. Therefore, more chlorine is used in the summer to keep bacteria levels in check. As the chlorine level increases, the formation of THMs also increase.

Water Temperature:

Because the source water is warmer in summer than at other times of the year, THMs form more quickly and in larger amounts during the summer months.

Organic Content:

Both the type and amount of organic matter in the source water can increase THM levels.

What is the allowable limit for THMs in our drinking water?

The current provincial standard and federal guideline is 100 ppb*. This guideline is outlined in Ontario Drinking Water Standards produced by Ontario.

*Note: One ppb is comparable to one second in 32 years, or 1¢ in $10,000,000.

What are the current levels of THMs in our central supply of drinking water?

The current yearly average of THMs is 40 ppb well below the federal/provincial drinking water limit. Ongoing monitoring of THMs occurs at both purification plants and throughout the distribution system.

How are guidelines determined?

A federal/provincial committee establishes national guidelines for certain substances that are known or suspected to have adverse effects on health. The THM guideline is designed to safeguard health, assuming lifelong consumption of drinking water.

How do we purify water at the purification plants?

Ottawa's drinking water is drawn from the Ottawa River and is treated at purification plants located at Lemieux Island and Britannia. Chlorine is used twice in the water purification process to kill bacteria.

  1. Disinfection at the Purification Plants
    As the river water enters the purification plants, enough free chlorine is added to kill bacteria, viruses, algae, etc.
  2. Disinfection in the Distribution System
    As the treated water leaves the purification plant, chloramine (chlorine mixed with ammonia) is added to preserve water quality as it travels through the distribution system. Chloramine is a very stable and long-lasting disinfectant. These are important characteristics considering the size of Ottawa's distribution system.

What are the benefits of using chloramine?

There are three primary reasons:

  • to provide a more stable and persistent disinfectant throughout the water distribution system;
  • to help reduce the levels of disinfection by-products such as THMs in the water;
  • to reduce the taste and odour of chlorine in tap water.

What is the City doing to reduce THM levels and to further improve the quality of drinking water?

The City is carrying out a number of process studies and experiments to optimize our existing treatment process. New methods of water purification and new disinfection strategies are tested at the City's Pilot Plant Research Facility, in partnership with several universities. These initiatives are underway to continually improve water quality and to better serve the needs of our expanding community.

Do I have to worry about THMs in my drinking water if I have a private well?

No, you should not be concerned as THMs are formed when chlorine reacts with organic material. Groundwater does not normally contain organic material, as it does not come into contact with vegetation. If you do use chlorine to disinfect your well water, the THM level will be very low.

Is the City's Medical Officer of Health satisfied with the quality of Ottawa's drinking water?

Yes. The Medical Officer is satisfied with the overall quality of drinking water in Ottawa and the efforts of the City to reduce levels of THMs. The City of Ottawa Health Services routinely review the results of the City’s ongoing water quality monitoring program.

Lead and drinking water

Answers to the most commonly asked questions about lead in drinking water. If you have a question that is not addressed, please call 3-1-1.

Is there lead in Ottawa's drinking water supply?

Drinking water supplied by the City is lead-free. However, trace amounts of lead can dissolve into drinking water during contact with plumbing materials in the home, such as lead pipes, brass fixtures, and lead solder. This may have an effect on the safety of tap water.

In most cases, lead concentrations in Ottawa’s tap water are well below the drinking water standard of 10 ppb (parts per billion), as established by Health Canada and the province of Ontario. Typical concentrations are as follows:

  • 0 ppb leaving Ottawa’s water treatment plants
  • 0 ppb for tap water in the majority of Ottawa homes (85%)
  • 1-5 ppb in most homes with lead service pipes

In some homes, the lead concentration can be higher than 10 ppb, usually due to the length of the water service pipe connected to the home.

What is a water service pipe?

A water service pipe connects a building (including residential homes) to the City’s municipal water supply.  The City owns and maintains the portion of pipe running from the water main to the property line, while property owners are responsible for the portion running from the property line to the home or building.

Who is impacted by lead in drinking water?

Approximately 15% of homes in Ottawa were originally constructed with water service pipes made of lead. Lead pipes were used in home construction up until 1955 – after that, water service pipes were made of copper. If the original lead service pipes have not been replaced there is the potential for lead to be present in your tap water.

Ottawa residents who live in homes built after 1955, as well as commercial and multi-residential properties are at little or no risk of lead exposure through tap water.

How do I know if I have a lead service pipe?

If your home was built after 1955, you do not have a lead service pipe.

For older homes, the best way to determine if a service pipe is lead or copper is to scratch the service pipe with sandpaper to expose bare metal. The visible portion of the pipe is approximately 50 cm in length, located between your basement’s concrete floor and the water meter. Lead pipes are dull grey in colour and are easily scratched by a hard object. Copper pipes are red-brown and corroded portions may show a green deposit.

Residents can call 3-1-1 to request a water quality test.

What is the current limit for lead in drinking water?

Health Canada and the Province of Ontario have established a maximum acceptable concentration for lead in drinking water of 10 parts per billion (ppb). This concentration aims to protect infants, young children and children in-utero who are most at risk of exposure to lead. Due to increasing concerns about negative health effects in children, Health Canada has proposed that the maximum concentration for lead in drinking water be reduced from 10 ppb to 5 ppb, although the lower standard has not yet been approved.

Should I be concerned about exposure to lead in drinking water?

Exposure to small amounts of lead can be harmful to human health, especially for infants, young children and children in-utero.  It is important to know that lead is present in several other environmental sources including soil, dust, food, air, and drinking water. Some household products such as jewellery, crystal, or ceramic pottery can also contain lead. Generally, household dust and food represent the highest lead exposure for young children.

Although the lead contribution from tap water is generally low, it can be significant in some homes with lead service pipes.

Is lead a concern in my children’s school or day nursery?

All schools and day nurseries in Ontario are required to flush plumbing regularly and test water for lead on an annual basis. A new regulation in Ontario requires that every water tap used for human consumption be tested for lead over a 3-year period.   

Ottawa Public Health is working with schools to ensure that lead-related issues are resolved and that schools comply with the Ontario Drinking Water Standards for lead in drinking water. More information is available from the Ontario Ministry of Environment and Climate Change (MOECC).

Who is responsible for replacing water service pipes?

The water service line that connects to your home is composed of two portions: a public portion owned by the City from the municipal water main to the property line, and a privately owned portion from the property line to the house. When a water main is replaced or upgraded, the City replaces the public portion of the lead service pipe with copper. Unless the homeowner pays to have their portion of the water service pipe replaced, it will remain as lead.

Is there assistance available to replace a lead service pipe?

Property owners are encouraged to take advantage of the Lead Pipe Replacement Program if their home was constructed prior to 1955. If the water service on private property is made from lead, residents can choose to replace it at their cost, and the City in turn will replace the public portion of the service pipe at the City’s cost. The program gives priority to applications from families with young children or pregnant mothers.

The cost to the property owner is generally between $2,000 to $4,000. These estimates do not include the removal and salvage of items such as furniture and fixtures, gardens, landscaping, decks, porches and interior work or finishes and the repair or replacement of these items upon the completion of the water service replacement.

The financial cost to the property owner can either be paid fully at the time of the pipe work, or can be appended to the household property taxes and paid over a 10-year period.

Are commercial and multi-residential properties impacted?

No. Lead has never been used for larger diameter pipes required for connections to larger buildings, schools, or institutions. Stronger materials such as copper, iron, or plastic are used to supply water to these buildings.

What is the City of Ottawa doing to reduce the risk of exposure to lead?

The City takes the following actions to mitigate the risk of exposure to lead in tap water:

  • The City adjusts the water supply pH to 9.2 – 9.4  in order to minimize the amount of lead and other metals that can dissolve into tap water.
  • Although Ottawa’s water supply meets regulatory standards for lead in drinking water, City staff are evaluating alternative treatment options and strategies to further reduce lead in tap water.
  • The City routinely monitors tap water lead concentrations in older homes through an extensive water sampling and testing program.

I live in a home with lead plumbing, what should I do to reduce the lead in my tap water?

Residents in homes with lead plumbing are encouraged to:

  • Run their tap for approximately 2 minutes to flush stagnant water sitting in the service pipe prior to cooking or drinking – this can greatly reduce lead concentrations in your tap water. The cost of water is approximately 2 cents for a two-minute tap flushing.
  • Keep a fresh jug of flushed tap water in the refrigerator for use during the day.
  • Contact the City at 3-1-1 to have their tap water tested for lead (at no charge).
  • Use an NSF-53 certified in-home filter to remove lead from tap water when using it for drinking and cooking purposes.
  • Take advantage of the Lead Pipe Replacement Program – a cost-sharing program whereby the City covers the cost of replacing the public portion of the lead service pipe and the resident pays for the private portion with the ability to repay over time (plus administration fees).

Who can I call to test my water?

Contact the City of Ottawa at 3-1-1 to have your tap water tested – there is no cost for this service.

Will my home's water filter remove lead from drinking water?

Most pitcher-style filters will reduce lead levels in your tap water to safe levels – most off the shelf filters reduce lead by about 90%. It is recommended that the filter unit be certified to meet the NSF/ANSI Standard 53 for the removal of lead. This information can be found on the label. You can complete an online search for an NSF-approved filter. It is important to change the filter cartridges as per manufacturer’s recommendations. The use of a reverse osmosis treatment system will remove lead completely.

Will boiling water remove the lead?

No, boiling your water does not remove lead. If boiled, the lead concentration of the water can actually increase slightly as the water evaporates.

Why do I have lead in my drinking water if I have copper pipes and no lead water service?

Lead may be present in solder used to join copper pipes and brass fittings and plumbing fixtures. However, lead contributions from brass and lead solder are typically quite low in the range of 1 ppb or less.

If I have lead service pipes, is it safe to wash dishes, clothing and shower?

Yes. Residue on clothing and dishes will not impact your health. Your skin will not absorb lead through bathing or showering.

Is bottled water lead-free?

Bottled water comes from various sources and is subject to inspection by the Canadian Food Inspection Agency under the Food and Drugs Act. Generally, most brands of bottled water have low or non-detectable concentrations of lead. The lead concentration is typically displayed on the bottle. Specific questions and concerns should be addressed to the company directly.

Who do I call if I have questions or concerns about water quality?

Contact the City of Ottawa at 3-1-1 if you require additional information or have questions about lead in Ottawa’s drinking water. You can also consult Health Canada for more information on lead and human health.

Fluoride in drinking water

What is fluoride?

Fluoride is a mineral that occurs naturally in soil, air and water. Fluoride helps to prevent tooth decay by re-mineralizing cavities when they first begin to form and increasing the resistance of tooth enamel to acids that cause tooth decay. Research has shown that people of all ages who regularly consume drinking water that has been fluoridated within recommended ranges, have between 15 - 40% fewer cavities.

Does Ottawa’s drinking water contain fluoride?

The City of Ottawa adds fluoride to the drinking water. The target level of 0.70 mg/L (ppm) of fluoride in the drinking water is maintained in accordance with a recent study entitled “Findings and Recommendations of the fluoride Expert Panel to Health Canada

The target level of 0.70 mg/L is within the 0.50 – 0.80 mg/L concentration range for fluoride suggested by the Ontario Ministry of the Environment, where fluoridation of drinking water is practiced.

Fluoride is not added to the water from the five communal well systems (Carp, Munster, Richmond, Shadow Ridge and Vars) owned and operated by the City. However, drinking water from these systems may contain naturally occurring fluoride in the range of 0.10 mg/L to 0.70 mg/L.

Why does Ottawa add fluoride to drinking water?

Under the direction of the Medical Officer of Health, Ottawa adds fluoride to adjust the natural concentration of the water supply to the level recommended for optimal dental care. This is a public health measure in accordance with provincial guidelines for drinking water and recommendations supported by the Ontario's Ministry of Health, Health Canada, the World Health Organization and American and Canadian Dental Associations.

Who monitors the level of fluoride in drinking water?

The fluoride level is continuously monitored at both City water treatment plants and by certified operators throughout the water distribution system. The results of the monitoring program are reviewed by Ottawa Public Health.

How is fluoride added to the drinking water?

The City of Ottawa uses Hydrofluorosilicic acid ( HFS ) to fluoridate drinking water. It comes in the form of a liquid solution that is delivered to the treatment plant in tanker trucks. Liquid HFS is added to drinking water during the final stage of the water treatment process. All chemicals used in water purification must be approved for application in potable water and must meet a number of product quality standards.

What about health concerns of adding fluoride to drinking water?

The possible effects of fluoride in drinking water is one of the most intensely researched areas of public health with several hundred recent publications. A number of recent, major reviews have been commissioned by governments around the world to examine the potential for adverse health effects related to fluoride (Australia, United Kingdom, United States, and Canada). As part of our ongoing review, the Ottawa Public Health Department has reviewed these major studies. All concluded that water fluoridation is a safe and effective method of reducing tooth decay at all stages of life.

To find out more about the benefits of fluoride, please visit Ottawa Public Health’s dental health web page.

What happens when the supply is interrupted?

Occasionally we stop adding fluoride for short periods during equipment maintenance and inform the Medical Officer of Health and the Ontario Ministry of the Environment of the interruption. When the interruption is finished we resume adding fluoride at the same level. We do not lower or raise the concentration to make up for interruptions in supply.

Who can I call to test my water?

Contact the City of Ottawa at 3-1-1 to have your tap water tested. There is no cost for this service.

In-home water treatment systems

How safe is my drinking water?

If you are part of the municipal water distribution system, your drinking water meets or is better than all provincial and federal drinking water standards. The City constantly monitors and tests its drinking water in accredited laboratories to ensure compliance with the Guidelines for Canadian Drinking Water Quality (Health Canada) and the Ontario Drinking Water Standards (Ministry of Environment) which provide the standard for safe drinking water. Municipal water does not require further treatment in the home.

Is the manufacture and sale of water treatment devices currently regulated in Canada?

The manufacture and sale of water treatment devices for home use is not regulated in Canada. The National Sanitation Foundation (NSF) in consultation with Health Canada has developed voluntary performance standards for water treatment devices and certification by the NSF is the only guarantee that a device can meet specified performance standards for removal of specific contaminants. For more information visit: www.nsf.org.

What types of in-home water treatment devices are available?

There are four major types of in-home water treatment devices:

  1. Granular activated carbon filters: Filters that can remove colour, taste, odours and some chemicals (certain types of organic chemicals, pesticides and chlorines) from water. Granular activated carbon filters by themselves will not remove lead and other heavy metals.
  2. Reverse osmosis units:  A reverse osmosis unit primarily removes dissolved salts, minerals and metals from the water.
  3. Distillation systems: Water distillation systems remove salt, minerals and heavy metals. They are typically not effective at removing organic compounds such as pesticides and trihalomethanes (THMs). Some distillation units also include a carbon filter that may remove organic compounds
  4. Water softeners: Dissolved calcium and magnesium make water “hard” when present in high concentrations. Water softening units (also called ion exchangers) remove calcium and magnesium ions from water and replace them with sodium ions. A water softener requires the regular addition of salt to regenerate itself and work properly.

Note: There are other devices on the market designed for disinfection of water from private wells, lakes, rivers or ponds. For more information on disinfection devices visit Health Canada’s website.

Should I buy an in-home water treatment device?

This is a personal decision. Water supplied by the City is well within federal and provincial guidelines and standards, is safe to drink and does not require further treatment in the home.

What if my water supply comes from a private well?

If you are not serviced by the City water distribution system and you rely on a private well, you should test your water supply on a regular basis. Groundwater quality varies across the City and your supply may benefit from a water treatment device to make it either safe to drink or to solve taste or odour problems. For further information on water treatment devices for well systems, contact the City of Ottawa Health Services or the Ministry of Environment (MOE) or contact our Water Information Line at 560-6089 and request the How Well is Your Well booklet in the publications section.

How to turn your water on and off

If interior plumbing work needs to be done in a home or building and shutting off the basement valve is not sufficient, the City of Ottawa can turn off the water to the property.

The water shut off and turn on fee is updated annually and can be found by visiting Water and Sewer Bill fees.

Please note:

  • These requests must be made at least three hours prior to the scheduled work by calling 3-1-1. Please keep in mind that during periods of high volume, the response time may extend beyond three hours.
  • If the water was turned off due to non-payment of a bill, please contact the City of Ottawa's Revenue Division at 613-580-2444.

Adjusting your water service post

A water service post controls water flow to a property and is usually located on the City side of the property line. It allows water to be shut off between the water main and the property. The top of the water service post should be visible and flush with the surrounding area, but seasonal expansion and contraction of the ground may change its height. A water service post will continue to function properly even if it is not flush with the surrounding area.

If your service post needs frequent adjustment, you may be able to do the work yourself, but note the following before doing any work:

  1. The property owner(s) is responsible if the water service post or water pipe is damaged while attempting to perform an adjustment on their own. 
  2. Anyone attempting to adjust the water service post should be in good health and know how to use the required tools. 

A demonstration of how to lower a water service post is below. To request a water service post adjustment by City staff please contact 3-1-1.

Place a wood block on top of the post and gently tap it with a small sledgehammer to lower it.

Water Service Post raised above grade

Man gently hitting wood block with sledgehammer to lower water service post

Water Service Post flush with grade

If the post has been high for many years, this method will not work and the post will have to be cut or excavated. In these instances the City will have to perform the workIf you own a new home please contact your builder to make the necessary adjustment.