Threats
Activities and conditions that pose threats to drinking water sources:
Pathogens, including bacteria; and chemicals, can harm human health.
To keep our drinking water safe and clean, we need to manage activities around municipal wells – especially where those wells are vulnerable.
In your area, some activities have the potential to harm drinking water sources.
These activities may include storage of sewage (including septic systems), fuel (including home heating oil), chemicals, storing or applying pesticides and fertilizers, and others.
When these types of activities take place near a municipal well there is a chance of impairing your local drinking water. That’s why we need your help to ensure activities are managed well to protect water sources.
The Province of Ontario created a law called the Clean Water Act, 2006 to reduce risk to your drinking water sources.
Ontario has listed 22 activities or conditions that could harm water sources and that need to be managed to reduce risk.
Activities are assessed as low, moderate, or significant threats to drinking water.
The level of threat depends on where the activities take place (for example, near a municipal well, on land that is vulnerable to contamination, etc.) and the circumstances (for example, the quantity and whether it is above or below the ground).
If you have any questions please phone or use our staff list or contact feedback form to reach your local risk management official or staff of the source protection region.
Together, we can keep our local municipal drinking water safe and clean.
- Septic systems; On-site sewage
- Fuel oil (for example, home heating oil)
- Liquid fuel (for example, large commercial fuel storage)
- Chemicals (for example, toxic chemicals such as organic solvents and dense non-aqueous phase liquids or DNAPLs)
- Commercial fertilizer
- Pesticides
- Nutrients (manure, bio-solids, grazing)
- Waste disposal sites (including storage of hazardous waste)
- Sewage works (sewage treatment plants, municipal sewers)
- Road salt and snow storage
List of 22 provincially prescribed drinking threats:
| Drinking Water Threat Activity – Prescribed by Regulation | Examples of Threat |
| 1. Establishment, operation or maintenance of a waste disposal site within the meaning of Part V of the Environmental Protection Act. | Storage of PCBs,waste oil and other hazardous waste; landfilling of hazardous, non-hazardous, municipal or commercial waste; land application of untreated septage. |
| 2. Establishment, operation or maintenance of a system that collects, stores, transmits, treats, or disposes of sewage. (Includes septic systems). | Septic systems,stormwater treatment ponds, discharge of industrial effluent, sewage treatment plants and sanitary sewer systems. |
| 3. Use of land as livestock grazing or pasturing land, an outdoor confinement area or a farm animal yard. | Fields where livestock graze, feed lots and confinement areas outside barns. |
| 4. Application of agricultural source material to land. | Manure produced by farm animals, and runoff from farm yards and manure storages, or wash water such as milking centre waste, or compost (such as mushroom compost). |
| 5. Storage of agricultural source material. | |
| 6. Management of agricultural source material. | |
| 7. Application of non-agricultural source material. | Land application of sewage bio-solids or other similar wastes such as pulp and paper bio-solids or waste materials from food processing. |
| 8. Handling and storage of non-agricultural source material. | |
| 9. Application of commercial fertilizer to land. | Nitrogen and phosphorus applied or stored for farm or commercial use (such as landscaping or golf courses). |
| 10. Handling and storage of commercial fertilizer. | |
| 11. Application of pesticide to land. | Specific categories of pesticides including: herbicides, fungicides, or those used as a soil fumigant to control fungi, nematodes, and weeds, for farm and commercial use.
Road salt,pickled sand in large quantities. |
| 12. Handling and storage of pesticide. | |
| 13. Application of road salt. | Road salt, pickled sand in large quantities. |
| 14. Handling and storage of road salt. | |
| 15. Storage of snow. | Snow storage over one (1) hectare. Municipal or commercial snow dumps. |
| 16. Handling and storage of fuel. | Gas stations and card locks or key locks, marinas, private storage such as farms and contractor yards, and heating oil tanks for homes and businesses. |
| 17. Handling and storage of a dense non-aqueous phase liquid or DNAPL. | Dense non-aqueous phase liquids (DNAPLs) and/or organic solvents may be found in dry-cleaning chemicals, paint and spot removers, rug cleaning fluids, varnishes, paints, lacquers, adhesives, glues, and de-greasing or cleaning agents, and substances used in the production of dyes, polymers, plastics, textiles, and printing inks. |
| 18. Handling and storage of an organic solvent. | |
| 19. Management of runoff that contains chemicals used in the de-icing of aircraft. | Large airports using ethylene glycol to de-ice aircrafts. |
| 20. An activity that takes water from an aquifer or a surface water body without returning the water taken to the same aquifer or surface water body. (This is a water quantity threat). | Water taken from groundwater and then discharged into a lake or river. Canning factories; bottling plants. |
| 21. An activity that reduces the recharge of an aquifer. | Water taken from groundwater and then discharged into a lake or river. Canning factories; bottling plants. |
| 22. Liquid hydrocarbon pipeline. | Liquid hydrocarbon pipeline |
A drinking water threat activity is any one of the 22 activities or conditions noted by the Province of Ontario in their list. Whether that threat is significant or not depends on how vulnerable the area is where it is taking place and other circumstances such as quantity and whether it is above grade or below grade.
For more information visit Ontario Provincial Tables of Threats and Circumstances.
A land-use activity, if not properly managed, can become a significant threat to drinking water sources in some municipal wellhead protection areas in our region. These activities – such as septic systems or home heating oil storage or pesticide application – can be significant in the most vulnerable areas around a municipal well:
- Within 100 metres of a municipal well (Wellhead protection area A or Zone A)
- Two-year time-of-travel area (Zone B)
- Five-year time-of-travel area (Zone C)
Hazards
How do you know the level of hazard to drinking water?
Not all threats are equal. The danger posed by particular chemicals or pathogens (including bacteria such as deadly E. coli O157: H7) depends on several factors including the amount, its toxicity, and how it behaves in the environment.
The Ontario Ministry of the Environment, Conservation and Parks (MECP) has identified many materials that could contaminate water. It has assigned a hazard rating to each using a 10-point scale based on the nature of the material and how it is used or stored.
The level of hazard, combined with the circumstances present which determine the likelihood of that hazard reaching a water source, help determine whether a threat is a significant drinking water threat.
Hazard rating factors for chemicals are:
- Toxicity
- Environmental fate
- Quantity
- Release to environment
- Type of vulnerable area (groundwater or surface water).
Hazard rating factors for pathogens are:
- Frequency of association with pathogens
- Release to environment
- Type of vulnerable area (groundwater or surface water)
For more information visit Ontario.ca.
The hazard ratings are reflected in the Provincial Tables of Threats and Circumstances.
Your local source protection committee, for the Maitland Valley and Ausable Bayfield source protection areas, has worked since 2007 to create effective, practical plans to protect your community’s drinking water sources. Those locally-developed plans have been approved by the Province of Ontario and they first took effect in April of 2015.
The policies with must-conform-to legal effect, such as risk management plans or prohibition, in the Ausable Bayfield Maitland Valley Source Protection Region, apply mostly to properties within 100 metres of a municipal well or in the most vulnerable parts of the two-year time-of-travel area.
Some legal-effect policies and future prohibitions also apply to some properties in the five-year time-of-travel area in the case of dense non-aqueous phase liquids (DNAPLs).
Call us, email us, or visit our website to find out more.
Staff members look forward to working with you to complete risk management plans and complete other actions that protect our community’s drinking water.
Some people living or working in vulnerable areas may need to do risk management plans. Call our Risk Management Office to find out more.
Prohibition of some activities also applies in some areas. In terms of existing land uses, management solutions are able to reduce risks to drinking water in most cases.
Persons, such as property owners and tenants, doing some land-use activities in some vulnerable areas, may have already received a letter if they are, or may be, undertaking a potential significant drinking water threat activity.
The vast majority of the people in the Maitland Valley and Ausable Bayfield source protection areas are not required to comply with plan policies. However, everyone is encouraged to read the source protection plans, have regard for the policies, and do what they can to reduce risk to drinking water sources.
Pathogens
Protecting drinking water sources includes reducing risk posed by chemicals, including organic solvents and dense non-aqueous phase liquids or DNAPLs; and pathogens (including deadly bacteria such as Escherichia coli O157:H7 (E. coli O157:H7).
There is a steep and terrible cost – a human cost and a financial cost – if drinking water sources are not adequately protected.
There have been international examples of the high cost of not protecting drinking water … and there have been examples very close to home.
More than 2,300 people became ill and seven people died when the drinking water system in Walkerton, Ontario became contaminated in May of 2000. The well system was contaminated with deadly bacteria: primarily Escherichia coli O157:H7.1 as well as Campylobacter jejuni.
Studies on E. coli O157:H7 in various soil types show that these pathogens survive at least 10 to 25 weeks.
Escherichia coli are bacteria that normally inhabit the large intestines of humans and other mammals. Most E. coli bacteria are harmless to healthy humans and do not cause disease. However, some forms of E. coli cause disease through the intestines.
E. coli O157:H7, a subgroup of E. coli, produces verotoxins that cause hemorrhagic colitis and, in some cases, hemolytic uremic syndrome (HUS). HUS is life-threatening. A person infected with E. coli O157:H7 can experience intestinal disease marked by diarrhea usually lasting about four days or more. Bloody diarrhea often occurs 24 hours after someone gets the illness. The infected person may experience severe abdominal pain.
E. coli O157:H7 infection can have very serious consquences to the elderly and to children under five years of age.
Verotoxins produced by E. coli O157:H7 can cause acute kidney failure, anemia, and low platelet counts, according to the Report of the Walkerton Inquiry. Verotoxin produced by E. coli O157:H7 can also affect small blood vessels in the brain.
Campylobacter jejuni is the most common type of Campylobacter bacteria that causes human illness. It is often found in feces of cattle, swine, sheep, goats, fowl, and wildlife, including birds and deer. Most human infections are caused by the ingestion of contaminated foods, usually undercooked poultry. Campylobacter jejuni can also be passed to humans through unpasteurized milk, direct contact with animals, person-to-person transmission, and water.
For more information visit this link: http://www.archives.gov.on.ca/en/e_records/walkerton/report1
It is much less expensive to protect a drinking water source than it is to replace or repair a damaged system or to pay for the consequences if water is not protected.
We thank you for taking positive action to protect local municipal drinking water sources (such as groundwater in aquifers underneath our feet and surface water from Lake Huron).
Questions?
Call our staff if you have questions about planning policies, vulnerability, threat activities, or how to manage threats and reduce risk to water.
Thank you for all you do to protect drinking water sources.
