Proposed amendments to the Director’s Technical Rules made under section 107 of the Clean Water Act, 2006

ERO number
Notice type
Clean Water Act, 2006, S.O. 2006, c. 22
Posted by
Ministry of the Environment, Conservation and Parks
Notice stage
Proposal posted
Comment period
August 11, 2020 - November 9, 2020 (90 days) Open
Last updated

This consultation closes at 11:59 p.m. on:
November 9, 2020

Proposal summary

We are proposing updates to the technical rules for assessing source water protection vulnerability and risk under the Clean Water Act to ensure that the quality of Ontario’s drinking water continues to be protected and that source protection efforts are supported by current science.

Proposal details

Our government is committed to protecting our lakes, waterways and groundwater supply, as outlined in our Made-in-Ontario Environment Plan.

To ensure that the quality of Ontario’s drinking water continues to be protected and that source protection efforts are supported by current science, the Ministry of the Environment, Conservation and Parks is proposing to update the Director’s Technical Rules for assessing vulnerability and risks under the Clean Water Act.

These technical rules are used by source protection authorities and municipalities to help develop and implement collaborative, watershed-based assessment reports and source protection plans that protect local drinking water supplies.

We invite feedback and input from the public, Indigenous communities and stakeholders across the province on these proposed updates, so that we can continue to protect Ontario’s water resources, now and for future generations.

The Clean Water Act

The goal of the Clean Water Act, 2006 is to protect existing and future sources of Ontario’s drinking water. A key focus of the legislation is the production of locally-developed, science-based:

  • assessment reports, developed in accordance with the technical rules, that describe the science of source protection including vulnerable areas, risk assessments, maps and activities that pose a threat to drinking water sources
  • source protection plans are action plans comprised of policies that address risks to sources of drinking water within vulnerable areas in a source protection area or region

Under section 107 of the Clean Water Act, the Director of the Source Protection Programs Branch may make rules for the science-based framework under the Act that include the technical methodologies for assessing vulnerability and risk. The Director's “Technical Rules: Assessment Report”, came into effect in November 2008, and the rules were last amended in March 2017.

Proposed updates to the Director’s Technical Rules

The proposed updates to the Director’s Technical Rules will:

  • reduce administrative burden for local decision-makers while maintaining technical rigour
  • provide clarity on the information required to evaluate whether drinking water systems are vulnerable to climate change impacts
  • clarify the intent of the rules around local threats are to be focused on activities that do not already require provincial or federal approval
  • adopt an evidence-based approach to delineating geographic areas where activities are cumulatively having a negative affect on the quality of drinking water
  • address administrative matters through minor clarifications and typographical corrections
  • clarify the Tables of Drinking Water Threats contained in the rules, which set out the circumstances under which prescribed activities pose a drinking water threat, to support plan implementation and a better understanding of the risks to drinking water as follows:
    • more accurately identify areas where the handling, storage and application of road salt may pose a risk to drinking water sources based on the lessons learned from the first round of source protection planning
    • provide a list of land use activities that may use, handle or store dense non-aqueous phase liquids
    • align the definitions of prescribed drinking water threats with other provincial regulations for storm water and other wastewater works, snow storage, non-agricultural source material, and waste
    • combine and simplify the circumstances of both handling and storage of fuel under one risk category
    • revise the hazard rating for above-grade handling and storage of fuel to recognize its significant risk to groundwater supplies.
    • clarify the commercial fertilizer circumstances to better reflect the actual risk posed
    • make editorial and administrative changes to the Tables to allow for ease of use and better search capabilities and better support the identification of risks and plan implementation

The attached document (see the Supporting Material section) “2020 Proposed Amendments to Technical Rules: Assessment Report-Clean Water Act” contains more details on the proposed updates to the Director’s Technical Rules, including the Tables of Drinking Water Threats.

Other information

We developed the updates to the Director’s Technical Rules in collaboration with:

  • source protection authorities
  • municipalities
  • other provincial ministries 

We incorporated their input and recommendations through working groups and consultation sessions. We also held five engagement sessions in November 2019 with key stakeholders to gather feedback.

The proposed updates will support municipalities and the source protection authorities in keeping assessment reports and source protection plans up to date to ensure they remain relevant, as well as support the implementation of source protection plans.

Supporting materials

View materials in person

Important notice: Due to the ongoing COVID-19 pandemic, viewing supporting materials in person is not available at this time.

Please reach out to the Contact listed in this notice to see if alternate arrangements can be made.


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