Source Water Protection

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What is source water protection?

Untreated water from lakes, rivers or groundwater aquifers that is used to supply drinking water systems is known as source water. Under the Clean Water Act, municipal drinking water sources must be protected from contamination and depletion .Source water protection (or ‘source protection’) safeguards public health from drinking water threats by raising awareness and protecting the drinking water supply. Municipalities must implement source protection plans to protect existing and future municipal drinking water sources from various threats.

The City of Ottawa encompasses two science-based, locally-developed source protection plans that contain policies to protect drinking water sources:

Source protection policies related to significant drinking water threats only apply within a Drinking Water Protection Zone. These vulnerable areas are also known as Intake Protection Zones (IPZ) and Wellhead Protection Areas (WHPA).  Different policies apply to different parts of the IPZ or WHPA because certain areas are more vulnerable to contamination.

Frequently Asked Source Water Protection Questions 

Why is source protection important?

Source protection safeguards public health by protecting the municipal drinking water supply. If water sources become contaminated, treatment can be much more expensive or even impossible.

How were Drinking Water Protection Zones determined?

Drinking Water Protection Zones were determined through a series of technical studies completed by the Mississippi-Rideau Source Protection Region and the Raisin-South Nation Source Protection Region.  These studies identified drinking water sources, areas vulnerable to contamination and what the potential sources of contamination might be.  The results of those technical studies were used to make source protection policy decisions and determine the areas where policies apply.

Assessment reports for the Mississippi-Rideau Source Protection Region and Raisin-South Nation Source Protection Region are available here:

What is a source protection plan?

A source protection plan contains policies to protect our current and future drinking water supplies from threats of contamination or overuse.  The plan was prepared by a local committee made up of representatives from municipalities, small business, industry, agriculture, environmental groups and the general public.

The Clean Water Act provides the legislative framework for Source Protection in Ontario. The Clean Water Act was enacted in 2006 in response to the Walkerton tragedy to protect Ontario’s drinking water sources as a part of an overall commitment to safeguard human health and the environment.

Under the Clean Water Act, sources of water to municipal drinking water systems must be studied and policies created to protect them from contamination and depletion.The Clean Water Act requires municipalities to implement Source Protection Plans to protect existing and future municipal drinking water supplies.

What are drinking water threats?

Under certain circumstances, the following can be significant threats to our drinking water:

  • Waste disposal sites
  • Septic systems
  • Sewage treatment plants and sewers
  • Manure, bio-solids, and livestock
  • Fuel and oil
  • Commercial fertilizer and pesticides
  • Road salt and snow storage
  • Chemicals and organic solvents
  • Aquaculture

How does the source protection plan address threats to drinking water?

The goal of the Source Protection Plan is to manage or eliminate activities that are, or could become, significant threats to drinking water sources. In most circumstances, property owners will be able to manage significant threats to reduce the risk and allow the activity to continue. The Clean Water Act provides several tools to accomplish the goal, such as outreach and education, risk management plans and changes to municipal land use planning documents. In some cases a combination of tools will work best.In general, the Source Protection Plan*:

  • Prohibits the future establishment of incompatible land uses such as landfills near drinking water sources
  • Requires governments to ensure that services such as sewers and winter road maintenance do not contaminate drinking water sources
  • Ensures that safeguards are in place to reduce the risk of activities such as fuel storage and chemical use
  • Encourages all residents and businesses in vulnerable areas to take voluntary action to protect the drinking water source

*This is a summary only, for information about specific policies and where they apply, please consult the Source Protection Plan for your area or contact the City of Ottawa Risk Management staff.

Where do source protection policies apply?

  • Intake Protection Zone (IPZ):  The area upstream of a surface water intake where land use activities have the potential to affect the quality of water.  The intake protection zone includes the water and land that surrounds the intake and takes into account the impacts of land uses and water activities.
  • Wellhead Protection Area (WHPA):  The area around the well where land use activities have the potential to affect the quality of water that flows into the well. These are areas of high vulnerability where the greatest care must be taken in the storage, use and handling of materials that could, if mishandled or spilled, pollute or contaminate a municipal well. 

Who is responsible for implementing and enforcing the source protection plan?

Provincial Ministries, Conservation Authorities, and Municipalities all have different responsibilities for implementing Source Protection Plans. Municipalities have the primary responsibility to implement and enforce policies locally to manage drinking water threats and to implement planning and restricted land use policies. The Ontario Ministry of the Environment and Climate Change is responsible for implementing policies related to activities that require provincial approvals. Source Protection Committees direct the development of the Assessment Reports and Source Protection Plans for each region. Conservation Authorities provide support and technical expertise to municipalities.

Am I located in a Drinking Water Protection Zone?

Use the following interactive map to determine if your home or business is located in a Drinking Water Protection Zone.

If located in a vulnerable area or to find more information, please consult the resources below or contact 3-1-1.