1. What are drinking quality water standards?

Drinking water quality standards are legally enforceable limits on contaminants in drinking water. They are designed to protect public health by limiting the amount of specific contaminants allowed in drinking water. Under Ontario's Safe Drinking Water Act (Safe Drinking Water Act) and the new Ontario Drinking-Water Quality Standards Regulation (O.Reg. 169/03), the province has established standards for numerous contaminants. Water supplied by drinking water systems subject to the Safe Drinking Water Act must legally meet these standards.

For more information, see the Safe Drinking Water Act FAQ.

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2. What contaminants do Ontario's drinking water quality standards cover?

Drinking water quality standards under O.Reg. 169/03 cover three different types of contaminants:

• Microbiological:

  The province has set standards for E. coli, fecal coliforms and total coliforms. Under O.Reg. 169/03 these parameters should not be detectable in drinking water. This Regulation also prescribes numerical limits for general bacteria populations that may be present in drinking water.

  Coliforms are bacteria common in the environment and come from human and animal waste. Although most are harmless, their presence may indicate that there are other harmful bacteria in the water.
  
  In addition, some bacteria can have a wide range of adverse health impacts -- they may cause acute illnesses such as gastroenteritis, or they may be a serious public health risk. For example, the infiltration of E. coli 157:H7 bacteria into a municipal well was a cause of seven deaths in Walkerton, Ontario, in May 2000.
  
  Operators at drinking water treatment plants are required to test regularly for coliform bacteria. The disinfection of drinking water by chlorination is designed to eliminate harmful bacteria.

  Other pathogens that can cause gastrointestinal illness include viruses and parasites such as giardia lamblia and cryptosporidium. These are not currently regulated under Ontario's drinking water quality standards.

• Chemical:

  The province has set numerical standards for both inorganic and organic chemicals. These standards are expressed in milligrams per litre (for example, 1.01 mg/l. for lead) as maximum concentrations allowed in drinking water.

  Many of the chemical contaminants come from industrial discharges or agricultural runoff into the source water, and are not necessarily removed by drinking water treatment. These chemicals can cause health problems if, over a lifetime, they are consumed in drinking water at levels above these limits. Mercury, for example, can cause kidney damage. Some organic chemicals, such as the pesticide alachlor, may pose an increased risk of cancer.

  The province has also set a numerical limit on total trihalomethanes. These chemicals are formed as a result of the chlorine treatment of drinking water and, at unacceptably high levels, can cause liver, kidney or central nervous system problems or increase the risk of cancer.

• Radiological:

  O.Reg. 169/03 prescribes numerical standards for natural and artificial radio nuclides. These standards are expressed as maximum allowable concentrations in becquerels per litre. Radiological contaminants include radio nuclides, such as radium 228, that result from the erosion of naturally-occurring deposits, or artificial radio nuclides, such as tritium, released into the water by nuclear power plants.
  
  For further information, Ontario's Drinking-Water Quality Standards Regulation (O.Reg. 169/03), including the numerical limits for these contaminants, can be found at:
  www.e-laws.gov.on.ca/dblaws/source/regs/english/2003/r03169_e.htm

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3. Does Ontario have drinking water quality standards for problems like taste and odour?

Like many other jurisdictions, Ontario has not regulated cosmetic or aesthetic problems in drinking water such as taste and odour.

Odour and taste, as well as colour and clarity, are considered to be aesthetic parameters, and not a risk to health. While the colour, taste or odour of drinking water may not have health effects, it is not desirable in drinking water. Research into the compounds, such as geosmin, that create musty taste and odour, particularly in Lake Ontario, can be found at: www.owwrc.com/TO.htm

The U.S. Environmental Protection Agency (EPA) has developed a chart that can be used as a general guide in determining the cause of any drinking water problems that consumers can smell, feel, taste or see. They suggest treatments that can be applied at the tap to reduce or eliminate these problems. This information can be found at: www.epa.gov/safewater/faq/signs.html

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4. How do contaminants find their way into drinking water sources?

Some contaminants found in drinking water sources may occur naturally, such as arsenic. The majority of contaminants, however, are the result of human activities and come from industrial discharges, agricultural runoff, sewage treatment plant outflows, nuclear power plants and other sources of pollution.

Not only are such contaminants directly discharged into waterways, but they may also find their way into water from aerial deposition and other pathways. These contaminants are not necessarily eliminated when drinking water is treated. Although the province has set standards for 78 contaminants, there are many chemicals in raw water for which no standards have been set, and many that are not even monitored.

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5. What contaminants are removed through drinking water treatments?

Raw water is treated by physical and chemical processes to remove contaminants. The standard treatments in Canada are coagulation, flocculation, sedimentation, followed by filtration and chlorination. Coagulation, flocculation, sedimentation and filtration remove dirt, bacteria, viruses and other impurities from the water. The final treatment is the addition of chlorine to disinfect and eliminate any organisms that might have survived the filtration process. Although these treatments do reduce the contaminants in drinking water, they are not designed to remove organic or inorganic chemicals, or radiological contaminants. Chlorine itself can combine with naturally occurring organic material in the water to form trihalomethanes.

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6. What is the federal role in establishing drinking water quality standards in Canada?

In Canada, a Federal-Provincial-Territorial Committee on Drinking Water develops and recommends national drinking water guidelines. It includes representatives of federal, provincial and territorial departments of health and the environment. It reviews toxicological and epidemiological evidence, and then makes recommendations on adding new substances to the guidelines or revising old guidelines. The Federal-Provincial-Territorial Committee makes recommendations for drinking water standards based on a process known as risk assessment. Provinces and territories then decide which of the guidelines to adopt for their jurisdictions. The provinces and territories may choose to adopt them as guidelines or as enforceable drinking water standards.

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7. How are drinking water quality standards set in Ontario?

For many years Ontario adopted the national guidelines as the Ontario Drinking Water Objectives. After the deaths at Walkerton in May 2000, the objectives were incorporated into enforceable regulatory standards, initially as O.Reg. 459/00 under the Ontario Water Resources Act, and then, in June 2003, as O.Reg. 169/03 under the Safe Drinking Water Act, 2002.

Currently, recommendations from the federal-provincial-territorial process are reviewed by Ontario, and if they are considered appropriate, they are then included in revisions to the schedules in the Regulation.

The Safe Drinking Water Act requires that Ontario establish an Advisory Council on Drinking-Water Quality and Testing Standards to consider issues relating to standards for drinking water quality and testing (although this section of the Act is not yet in force). This Council may publish information in the electronic registry, established under the Environmental Bill of Rights. The recommendations of the Advisory Council are to be considered by the Minister of the Environment in establishing and revising standards for drinking water quality and testing, although the Minister is not legally obliged to adopt them.

For more information on the Environmental Registry, see the web site of the Environmental Commissioner of Ontario.

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8. Can drinking water quality standards be changed?

Drinking water quality standards are not static, and some standards can, and do, change over time. Emerging threats like cryptosporidium, or concerns such as endocrine disruption, need to be considered. Moreover, there may be new scientific evidence of harm from an already regulated contaminant, or new advances in treatment technology that mean a more stringent standard could be adopted.

The Federal-Provincial-Territorial Committee posts a list of priority contaminants that are candidates for guidelines or standards, as does the U.S. Environmental Protection Agency.

Aside from participating in this Committee process, Ontario does not yet have a formalized system for examining new candidate substances for regulation or for revising current standards. Under the Safe Drinking Water Act, however, once the required Advisory Council is established, it would be empowered to make recommendations on revising old standards or establishing new standards not on the federal-provincial agenda. As of June 1, 2003, the section of the Act establishing the Advisory Council had not been proclaimed in force.

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9. How can I participate in the standard-setting process?

The Federal-Provincial-Territorial Committee on Drinking Water posts summaries of its proceedings on its web site. It also posts proposed recommendations and supporting technical evidence. Members of the public may comment on these recommendations when they are being considered. See:
www.hc-sc.gc.ca/hecs-sesc/water/sub_committee.htm

The report of Justice O’Connor after his inquiry made recommendations to strengthen public involvement in setting standards for drinking water. He recommended that the federal-provincial-territorial process for proposing drinking water quality guidelines be refined to provide for greater transparency and public participation.

Justice O'Connor also saw the yet-to-be-established Advisory Council on Drinking-Water Quality and Testing Standards as an important means of increasing transparency and public access in the standard-setting process. The Council would solicit public views on proposed regulations, and its recommendations to the Minister of the Environment would be made public. The Advisory Council would also have the ability to hold public hearings on matters of broad public concern. He recommends that the Advisory Council make full use of the Environmental Bill of Rights Registry to post proposals.

In the meantime, the public can use their participation rights under the Environmental Bill of Rights in order to address drinking water quality issues. For example, if the Ministry of the Environment proposes to revise the current standards in Reg. 169/03, then notice of this proposal should be placed on the Environmental Registry, and a public comment period should be provided.

Similarly, if citizens believe that a current standard is outdated or inadequate, then an Application for Review can be filed under Part IV of the Environmental Bill of Rights.

For further information on these and other public participation rights, see the web site. of the Office of the Environmental Commissioner.

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10. How can I find out if my drinking water meets current Ontario standards?

Under Ontario's Drinking-Water Systems Regulation (O.Reg 170/03), owners of drinking water systems are required to prepare annual reports. The results of all drinking water tests must be reported, including the total number of adverse results. A copy of the annual report prepared by your drinking water supplier must be given to you upon your request and without charge. It must also be provided to the office of every "designated facility" (such as schools or health care facilities) served by the drinking water system.

For large municipal residential systems serving more than 10,000 people, the annual reports must be available for free on a web site. on the Internet. The water quality report of the City of Toronto, for example, may be found at: www.city.toronto.on.ca/water/quality_report.htm

On its web site. the Association of Municipalities of Ontario lists municipal web sites in Ontario, where water quality reports should be accessible, at: http://199.202.235.157/ylg/ontario.html

In addition, test results must be available for inspection by members of the public without charge during normal business hours at the office of the owner. If the owner's office is not at a reasonably convenient location, then the report must be available at another location that is convenient. If the drinking water system serves a municipality, the information must be available at the office of the municipality whether or not the municipality owns the system.

You can also find more immediately available information on specific “adverse drinking water quality incidents” on the web site. of the Ministry of the Environment. Instances in which water quality standards in Ontario have been exceeded are listed according to region. However, the Ministry only reports health-related adverse water quality incidents involving high levels of E. coli or fecal coliforms, or where a boil water advisory or order has been issued. These incident reports can be found at:
www.ene.gov.on.ca/envision/adverse/adversewater.htm

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11. What happens if the drinking water exceeds the Ontario drinking water quality standards?

Ontario's Drinking-Water Systems Regulation (O.Reg. 170/03) specifies that when adverse test results are obtained, then verbal and written notice must be given immediately to the Ministry of the Environment, and to the local Medical Officer of Health. This reporting obligation is imposed upon the owner/operator of the drinking water system, as well as upon the laboratory that performed the testing.

This Regulation also prescribes the "corrective action" that must be undertaken after adverse test results have been reported. Depending on the nature of the problem, "corrective action" may include: resample and test; increase chlorination; and other steps as may be directed by the Medical Officer of Health.

In addition, owners of certain drinking water systems are required to post warning notices if they are not doing the required microbiological tests for coliforms. These notices must be posted in prominent locations to alert users of the system that the water may not be safe.

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12. What is Canadian Environmental Law Association’s position on drinking water quality standards?

The Canadian Environmental Law Association (CELA) has always supported the creation of a Safe Drinking Water Act, and setting enforceable standards for contaminants in drinking water. However, meaningful public participation is necessary for determining what standards should be adopted and which ones should be revised. CELA would like a periodic review of the Act and the regulation governing drinking water standards. In addition, CELA believes that community-right-to-know principles should be strengthened in the Act. For example, all annual drinking water reports should be mailed to consumers so that this information is easily accessible.

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13. How can I get more information about the drinking water quality standards in Ontario?

The Ontario Ministry of the Environment has more information on the Safe Drinking Water Act and other drinking water concerns at: www.ene.gov.on.ca/water.htm

The Safe Drinking Water Act, 2002 and Regulations are available at:
www.ene.gov.on.ca/envision/water/sdwa/index.htm and at: www.e-laws.gov.on.ca/

The Report of the Walkerton Commission of Inquiry, part 2, chapter 5, contains information on Justice O'Connor's recommendations regarding drinking water quality standards. Appendix A contains an interjurisdictional comparison of water quality standards. The Report is available at:
www.attorneygeneral.jus.gov.on.ca/english/about/pubs/walkerton/

The Canadian Drinking Water Guidelines are available at: www.hc-sc.gc.ca/hecs-sesc/water/dwgsup.htm

The U.S. EPA has a strong Safe Drinking Water Act. For a comparison of Ontario's Act with the U.S. SDWA, see the CELA publication: “The Establishment and Implementation of the Safe Drinking Water Act in Ontario: Some Helpful Lessons from the United States (Speaking Notes) Meeting Your Obligations Under Ontario’s New Safe Drinking Water Act”.

For more information on the Safe Drinking Water Act see the Safe Drinking Water Act FAQ and for information on bottled water, see the Bottled Water FAQ.

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14. How can I get information about standards in other jurisdictions?

For information on drinking water standards and the standard-setting process in other jurisdictions, see:

A guide to the water legislation of all Canadian provinces, and drinking water legislation where it exists, can be found at: www.csae-scgr.ca/Othernews/Waterlaws.shtml

The World Health Organization’s current edition of its Guidelines for Drinking Water Quality is available at:
www.who.int/water_sanitation_health/dwq/guidelines2/en/

For the United States, the Environmental Protection Agency’s Office of Ground Water And Drinking Water lists information about U.S. standards and how they are set at: www.epa.gov/OGWDW/mcl.html

For environmental legislation in Europe including drinking water standards set by the European Union, see: http://europa.eu.int/comm/environment/legis_en.htm

For drinking water standards in Australia, see:
www.health.gov.au/nhmrc/publications/synopses/eh19syn.htm

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