Nitrates FAQs

The following outlines important information related to nitrate levels in drinking water. 

Is the City’s drinking water safe?

Yes, the City’s drinking water is safe and meets all Ontario’s Drinking Water Standards. The City of Brantford places the highest priority on the safety and well-being of our community. We are committed to ensuring that all residents have access to safe and reliable drinking water. Brantford’s water supply is rigorously tested multiple times each day to ensure it meets or exceeds all provincial health and safety standards. These testing measures are part of our ongoing responsibility to maintain compliance with strict regulatory requirements and to provide the highest level of confidence in the quality of water delivered to homes and businesses across the city. 

Should there be a need to inform the public of any changes that could adversely affect public health, the City is fully committed to public transparency, and in consultation with the Grand Erie Public Health will provide clear communications to ensure the community is informed and any necessary actions to protect public health are taken promptly.

What is Nitrate?
Nitrate is a naturally occurring odourless and colourless chemical compound made up of nitrogen and oxygen and is naturally present in the soils, water, air and plants. It is an essential ingredient for the growth of plants and animals.
Where is Nitrate most present?

Nitrate is commonly found in diets through vegetables and fruits, cured and processed meats, fish, dairy products, beers, and cereals. Some meats and meat products contain nitrate which is used as a preservative. Manure and some fertilizers are high in nitrate. Drinking water from wells and surface water can also contain nitrate.

The main source of exposure to nitrates for the general population is via food (either naturally occurring or added as a preservative), followed by drinking water. Nitrate taken up by plants (especially leafy vegetables) can account for about 80% of nitrate in a typical diet.

How does Nitrate get into water in the Grand River?

Nitrate occurs naturally in surface water and groundwater at low levels. They are highly soluble in water so any excess amount of fertilizer rich in nitrate and not consumed by plants in the winter months can move quickly through soil and into surface water and groundwater under certain conditions. High levels of nitrate can also occur from non-point sources such as runoff from agricultural fields, livestock operations and point sources including some wastewater treatments plants that convert ammonia to nitrate and discharge effluent to the Grand River or its tributaries.

During colder months, biological processes in the river slow down considerably, reducing the uptake of nitrogen and increasing the potential for elevated nitrate concentrations. Large runoff events may also have the potential to export large quantities of nitrate to receiving streams and rivers.

What is the acceptable level of Nitrate in drinking water?
The Ministry of the Environment, Conservation and Parks (MECP) has set a Maximum Acceptable Concentration (MAC) for nitrate at 10 milligrams per Litre as nitrogen. No harmful health effects have been seen at levels below the drinking water guideline level of 45 mg/L of nitrate in drinking water (equivalent to 10 mg/L expressed as nitrogen-nitrate).
What health effect does nitrate have on humans?

The Ministry of the Environment, Conservation and Parks (MECP) has set a Maximum Acceptable Concentration (MAC) for nitrate at 10 milligrams per Litre (mg/L) as nitrogen. No harmful health effects have been seen at levels below the drinking water guideline level of 45 mg/L of nitrate in drinking water (equivalent to 10 mg/L expressed as nitrogen-nitrate).

Health Canada warns that the main health threat to the public when nitrate is over 10mg/L is methemoglobinemia, also known as blue baby syndrome. Therefore, the vulnerable populations at risk from ingesting high nitrate in drinking water, are expecting mothers, bottle-fed infants less than six months old, and babies one year old and under. Infants six months old or under do not yet have the enzyme needed to break down nitrate. There is no conclusive evidence that temporary consumption of water measuring 10 mg/L is harmful to anyone outside of the identified vulnerable populations of expecting mothers bottle-fed infants less than six months old, and babies one year of age and under.

For more information, please refer to the Grand Erie Public Health (formerly known as Brant County Health Unit) website and/or call 519-753-4937 ext. 440.

Residents are also encouraged to review the guidelines issued by Health Canada at Guidelines for Canadian Drinking Water Quality: Guideline - Nitrate and Nitrite.

Will Nitrate over 10 mg/L affect adults?

For more information regarding potential public health impacts, please refer to Grand Erie Public Health (formerly known as Brant County Health Unit) website.

How does the City know that there is nitrate in the public water supply?
The only way to know if you have low or high levels of nitrate in your drinking water is to have it tested by a licensed and accredited laboratory. Municipal drinking water systems including the City of Brantford are required, as per regulations, to have their water tested on a regular basis and provide the results to the public. When nitrate levels are higher in the Grand River, the City increases the testing frequency in the water to ensure that our community is protected. The public is strongly urged NOT to use nitrate test kits that are available on the market, as in most cases have shown to be unreliable. 
Can high Nitrate water be treated at home?
Yes. Three effective home treatment devices that remove nitrate are ion exchange, distillation or reverse osmosis. Each of these methods are expensive options. For short term exposure, the most cost-effective alternate source of water is bottled water that is low in nitrate. The City strongly urges residents to beware of door-to-door salesperson using high pressure sales tactics while instilling fear to sell exorbitantly priced water treatment equipment. 
Can the City treat the water supply to eliminate or reduce nitrate?

The City of Brantford operates and maintains the City’s Water System and is committed to ensuring a high level of trust, commitment and accountability for the public water supply by consistently delivering high quality and safe drinking water to our community. In November 2024, the Grand River Conservation Authority (GRCA) awarded the City of Brantford Wastewater Treatment Plant a Gold Recognition award for their efforts to improve water quality in the Grand River.

The City closely monitors nitrate levels in the water every winter, and to date, this has not been an issue. While the current water treatment plant does not have the expensive technology to reduce or remove nitrate from the Grand River water, proactive planning is underway to explore short-term and long-term solutions.

The Grand River Conservation Authority website is showing nitrate level in the Grand River. Is the nitrate level shown accurate?
The Grand River Conservation Authority monitors nitrate levels in the Grand River at Brant Park and Bridgeport river monitoring stations. During high-flow events, the water is very turbid (murky) and this decreases the accuracy of the optical sensors. As such, the nitrate concentration readings from the GRCA sensors can over-estimate the actual nitrate concentration in the river. The GRCA nitrate sensor readings are not intended to be used for operational or regulatory decision making, but rather as a tool for early detection of increasing trends.
How long do nitrate levels that are over the maximum allowable concentration (MAC) of 10 mg/L last for?
Nitrate levels within the drinking water supply did not reach the MAC of 10 mg/L so far. The Grand River water data that the City of Brantford and the Grand River Conservation Authority has collected thus far shows that the nitrate levels in the Grand River can be elevated for periods ranging from hours to days. Episodes of high nitrate levels are dependent on river and weather conditions including significant snow melt, and heavy rain.
How is the City planning to address increasing nitrate levels in the public drinking water supply?

To maintain a reliable drinking water supply for the long-term, the City has a three prong muti-barrier approach that includes the following actions:

  • A clean safe Grand River water (source water) is necessary for the continued long-term security of the City’s drinking water supply. The City, in coordination with the Grand River Conservation Authority and the Ministry of Environment, Conservation and Parks is working to leverage the Clean Water Act to explore ways to reduce nitrate discharge to the Grand River in the watershed.
  • The City is working to implement an effective short-term and long-term water treatment solution to remove nitrate and increase the ability to store more water for emergency use.
  • The City has an emergency plan in the unlikely event that the nitrate level in the Grand River exceeds the MAC of 10 mg/L for an extended period. As per the plan, the City will supply drinking water from the City’s storage reservoirs until nitrate levels in the Grand River water reduce below the 10mg/L threshold. In the unlikely event that nitrate level stays above the limit for a longer period, the City will supply bottled water or hauled potable water for identified vulnerable populations for cooking and drinking. The public will be informed of all and any measures necessary to protect public health.
Is there any financial assistance available for low-income families to install a reverse osmosis device at home in the unlikely event that nitrate level is above the drinking water standard for an extended period?

Low-income families can apply to Ontario Renovates Program to determine eligibility for subsidy to purchase and install an appropriate Reverse Osmosis device at home to reduce the nitrate level in the tap water. For further details of the Program, please visit our Funding for Home Repairs and Home Ownership page here.

If the nitrate levels in the Drinking water are over the provincial limit, can I boil the water and consume?

Please refer to Grand Erie Public Health (formerly known as Brant County Health Unit) website for instructions on use of tap water by the vulnerable population (pregnant women, bottle fed infants of less than six months old and babies less than 1 year old) 

How do I learn more about Brantford’s drinking water quality?

The City regularly posts the drinking water quality reports on the City’s website. The reports can be found online here.

For more information residents can call the City’s Customer Contact Centre at 519-759-4150.