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 your home’s lead pipes (including your water service pipe), brass fixtures, and lead solder. This may impact the safety of your 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 the Province of Ontario. Typical concentrations are as follows:
- 0 ppb leaving Ottawa’s water treatment plants
- Less than 1 ppb for tap water in the majority of Ottawa homes (85%)
- 1-5 ppb in older homes with lead water 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.
Please note: Due to increasing concerns about negative health effects in children, Health Canada has established a new maximum allowable concentration for lead in drinking water of 5 ppb. The Province of Ontario is currently reviewing its maximum allowable concentration of 10 ppb and will be implementing a revised Ontario Drinking Water Standard, although the timeline has not been determined.
What is a water service pipe?
A water service pipe connects a building to the City’s municipal water supply. Property owners are responsible for the pipe from their home to the water shut-off valve (referred to as the private portion) and the City owns and maintains the pipe from the water shut-off valve to the watermain (referred to as the public portion).
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 the 1950s. After that, water service pipes were made of copper. If the original lead water service pipe has not been replaced there is the potential for small amounts of lead to dissolve into household 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.
Post-1955 homes connected to older watermains
In limited instances, properties built after 1955 may be connected to an older watermain. In this situation, while your private water service pipe (from the water shut-off valve to your home) likely does not contain lead, the City (public) portion of the water service pipe (from the City’s watermain to the water shut-off valve) may contain lead.
To ensure your water service pipe is correctly assessed, we recommend that you call 3-1-1 to inquire about the age of the watermain.
How do I know if I have a lead water service pipe?
The best way to determine if your water service pipe is lead or copper is to scratch the service pipe with sandpaper to expose bare metal. The only visible portion of the water service pipe is 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.
What is the current limit for lead in drinking water?
Due to increasing concerns about negative health effects in children, Health Canada has established a new maximum allowable concentration for lead in drinking water of 5 parts per billion (ppb). The Province of Ontario is currently reviewing its maximum allowable concentration of 10 ppb and will be implementing a revised Ontario Drinking Water Standard, although the timeline has not been determined.
The maximum allowable concentration of lead in drinking water aims to protect infants, young children and children in-utero who are most at risk of exposure to lead.
Should I be concerned about exposure to lead in drinking water?
Exposure to small amounts of lead is especially harmful for pregnant women and can have harmful effects on a child’s development.
Lead can be present in many environmental sources including soil, dust, food, air, and drinking water. Some household products such as jewellery, crystal, and ceramic pottery can also contain lead. Household dust and dirt often represent the greatest lead exposure for young children.
Although the lead contribution from tap water is generally low, it can be significant in some homes with lead water service pipes.
Visit Health Canada's website for more information on lead and human health, or contact Ottawa Public Health at 613-580-6744 (TTY: 613-580-9656), or by email at healthsante@ottawa.ca.
Is lead a concern in my children’s school or child care centre?
All schools, private schools and child care centres in Ontario are required to flush plumbing regularly, test water for lead annually, and take immediate action if levels exceed the Ontario Drinking Water Quality Standard of 10 ppb. As of July 2017, every drinking water fountain and any tap that provides drinking water or is used to prepare food or drink for children under 18 must be sampled for lead.
Ottawa Public Health ensures that schools, private schools and child care centres resolve lead-related drinking water issues and therefore comply with Ontario Drinking Water Standards. More information is available from the Ontario Ministry of Environment, Conservation, and Parks (MECP).
Who is responsible for replacing water service pipes?
The water service pipe that connects to your home is composed of two portions: a public portion owned by the City from the City’s watermain to the water shut-off valve, and a privately-owned portion from the water shut-off valve to your home. 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 water service pipe?
Property owners are encouraged to take advantage of the Lead Pipe Replacement Program.
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 to minimize the amount of lead and other metals that can dissolve into tap water.
- The City routinely monitors tap water lead concentrations in older homes through an extensive water sampling and testing program.
- 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 will test your tap water for lead, free of charge. Call 3-1-1 for this service.
I live in a home with lead plumbing. What should I do to reduce the lead in my tap water?
To minimize lead exposure from tap water, residents 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. Ensure the jug or container itself is lead-free.
- Request to have your home’s drinking water tested for lead.
- Use a tap or pitcher-style filter to remove lead from tap water when used for drinking and cooking. Many water filters will sufficiently remove lead from tap water, but the City recommends a filter certified to the NSF/ANSI 53 standard for lead removal. Residents can complete an online search for an NSF-certified filter.
- Tap faucets and fixtures used for drinking water should be certified to the NSF/ANSI 372 standard as lead-free.
- Take advantage of the Lead Pipe Replacement Program to help with the replacement of a lead water service pipe.
How can I have my tap water tested for lead?
If you’re concerned about the potential presence of lead in your tap water, you can request a water quality test.
Is there a recommended time of year to have my tap water tested for lead?
Lead testing of tap water can be conducted at any time throughout the year, but testing during the summer months is recommended for the most accurate results. Water temperature at the tap significantly impacts lead testing results. The highest lead concentrations (representing the worst-case for a given property) are typically observed from May to September. Warm water temperatures during this period increase the amount of lead that dissolves from lead service pipes, internal plumbing, and tap fixtures.
During the winter months, the temperature of the Ottawa River, the City’s source water, is close to 0°C, resulting in a temperature of approximately 5-10°C at the tap. As a result, lead concentrations at the tap are quite low and often non-detectable during winter. To be more protective for your health, sampling in the warmer months (May to September) is recommended.
Will my home water filter remove lead from drinking water?
Most pitcher-style filters will reduce lead levels in your tap water to safe levels; however, it is recommended that the filter unit be certified to the NSF/ANSI 53 standard 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.
What are other potential sources of lead in my drinking water?
Lead may be present in solder used to join copper pipes as well as in brass used in the faucets and plumbing fixtures in your home. However, lead contributions from brass and lead solder are typically quite low (in the range of 1 ppb or less).
If I have a lead water service pipe, 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.
Will lead in tap water affect my pet?
Lead poisoning in cats and dogs is extremely uncommon, particularly from water. Pets can be harmed by high levels of lead exposure from other sources, most commonly dust from lead paint during household renovations, or hobby-related materials that use lead, such as fishing tackle, stained glass or ceramics. If you are concerned about your pet’s health, contact your veterinarian for more information.
Who do I call if I have questions or concerns about my water quality?
Call 3-1-1 if you require additional information or have questions about keeping your tap water lead-free.