Regulatory Resources for Ontario Systems

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The following links are sorted by their relevance to categories of drinking water systems.

If you are unsure of what regulation your system falls under, the documents below provide information on O. Reg. 170/03 and O. Reg. 319/08 systems.

Drinking Water Systems Under O. Reg. 170/03

Drinking Water Systems Under O. Reg. 319/08

Visit our online library’s main webpage to find more resources on topics related to drinking water.


Large O. Reg. 170/03 Systems

2015 Watermain disinfection procedure

2020 Watermain disinfection procedure

A Guide for Drinking Water System Owners Seeking To Undertake a Backflow Prevention Program

A Student’s Guide to Drinking Water and Wastewater Operator Certification

Certification Guide for Operators and Water Quality Analysts of Drinking Water Systems

Clean Water Act, 2006

Design Guidelines for Drinking-Water Systems

Drinking Water Operator-In-Training Requirements

Experience as a Drinking Water Operator

Find Licensed Well Contractors

Guide for Applying for Drinking Water Works Permit Amendments, License Amendments

Guide for Applying for Fragmentation and Relief from Regulatory Requirements

Guide to Permit to Take Water Application Form

Guide to Supporting Information Required for a Municipal Drinking Water License Renewal

Laboratories Licensed to Test for Lead

List of Licensed Laboratories

Notice of Adverse Test Results and Issue Resolution

Ontario’s Drinking Water Quality Management Standard – Pocket Guide

Ontario Water Resources Act, R.S.O. 1990, c. O.40

O. Reg. 128/04: Certification of Drinking Water System Operators and Water Quality Analysts

O. Reg. 169/03: Ontario Drinking Water Quality Standards

O. Reg. 170/03: Drinking Water Systems

O. Reg. 248/03: Drinking Water Testing Services

O. Reg. 284/07: Source Protection Areas and Regions

O. Reg. 387/04: Water Taking and Transfer

Overall Responsible Operator vs. Operator-in-Charge

Permits to Take Water

Practices for Collection and Handling of Drinking Water Samples

Procedure for Disinfection of Drinking Water in Ontario

Questions and Answers – Watermain Disinfection Procedure

Report a Spill

Request for Early Implementation of the Watermain Disinfection Procedure

Required Qualifications to Operate, Test or Sample Drinking Water Systems

R.R.O. 1990, Reg. 903: Wells

Safe Drinking Water Act, 2002

Taking Care of Your Drinking Water: A Guide for Members of Municipal Councils

Technical Support Document for Ontario Drinking Water Standards, Objectives and Guidelines

Training Requirements for Drinking Water Operators

Water and Energy Conservation Guidance Manual for Sewage Works

Watermain Disinfection Procedure

Water Quality Analyst Experience and Director Approved Course

Water Supply Wells: Requirements and Best Practices

Well Regulation – Well Construction Licensing (technical bulletin)

Well Regulation – Well Maintenance (technical bulletin)

Wells Regulation – Completing the New Well’s Structure (technical bulletin)

Wells Regulation – Flowing Wells (technical bulletin)

Wells Regulation – Installing Equipment in a Well (technical bulletin)

Wells Regulation – New Construction of the Hole, Casing, Well Screen and Annular Space (technical bulletin)

Wells Regulation – Siting a New Well (technical bulletin)

Wells Regulation – Well Abandonment: How to Plug and Seal a Well (technical bulletin)

Wells Regulation – Well Abandonment: When to Plug and Seal a Well (technical bulletin)

Wells Regulation – Well Disinfection (technical bulletin)

Wells Regulation – Well Repairs and Other Alterations (technical bulletin)


Small O. Reg. 170/03 Systems

A Guide for Operators and Owners of Drinking Water Systems that Serve Designated Facilities

A Guide for Owners and Operators of Non-Municipal Year-Round Residential Drinking Water Systems

Application Form for Fragmentation or Relief from Regulatory Requirements form

Declaration of Professional Engineer and Notice of Completion for changes to a drinking water system

Drinking Water System Profile Information form

Find Licensed Well Contractors

Flushing and Sampling for Lead

Flushing Plumbing in Schools, Private Schools and Day Nurseries

Flushing your Plumbing: At-a-glance guide for schools, private schools and child care centres

Guide for Applying for Drinking Water Works Permit Amendments, License Amendments

Guide for Applying for Fragmentation and Relief from Regulatory Requirements

Guide for Schools, Private Schools and Day Nurseries on Flushing and Testing for Lead

Guide to Permit to Take Water Application Form

How to Maintain Your Certification: Operators of Limited Groundwater & Limited Surface Water Subsystems

How to Maintain Your Trained Person Designation

Identify and control excess lead in drinking water in schools and child care centres

Laboratories Licensed to Test for Lead

Laboratory Services Notification for adding or changing labs

List of Licensed Laboratories

Notice of Adverse Test Results and Issue Resolution

Ontario Drinking Water Regulations for Small Systems

O. Reg. 128/04: Certification of Drinking Water System Operators and Water Quality Analysts

O. Reg. 169/03: Ontario Drinking Water Quality Standards

O. Reg. 170/03: Drinking Water Systems

O. Reg. 243/07: Schools, Private Schools and Day Nurseries

Permits to Take Water

Practices for Collection and Handling of Drinking Water Samples

Procedure for Disinfection of Drinking Water in Ontario

Providing Safe Drinking Water to Cisterns at Non-Residential Drinking Water Systems Serving Designated Facilities

Providing Safe Drinking Water to the Public: A Guide for Owners and Operators of Non-Municipal Year-Round Residential Drinking Water Systems

Providing Safe Drinking Water to the Public: A Guide for Operators of Seasonal and Non-Residential Drinking Water Systems

Questions and Answers – Watermain Disinfection Procedure

Report a Spill

Request for Early Implementation of the Watermain Disinfection Procedure

Required Qualifications to Operate, Test or Sample Drinking Water Systems

R.R.O. 1990, Reg. 903: Wells

Rules for non-municipal drinking water systems

Safe Drinking Water Act, 2002

Sampling for Lead: At-a-Glance guide for schools, private schools and child care centres

Sampling for Lead in Schools, Private Schools and Day Nurseries

Steps to Become a Limited System Operator: Operator Certification Requirements for Small Drinking Water Systems

Steps to Become a Trained Person: Operators of Small Drinking Water Systems Serving Designated Facilities

Technical Support Document for Ontario Drinking Water Standards, Objectives and Guidelines

Trained Person Designation

Training Manual for Supervised Persons Conducting Operational Checks

Watermain disinfection procedure

Water Supply Wells: Requirements and Best Practices

Well Regulation – Well Construction Licensing (technical bulletin)

Well Regulation – Well Maintenance (technical bulletin)

Wells Regulation – Completing the New Well’s Structure (technical bulletin)

Wells Regulation – Flowing Wells (technical bulletin)

Wells Regulation – Installing Equipment in a Well (technical bulletin)

Wells Regulation – New Construction of the Hole, Casing, Well Screen and Annular Space (technical bulletin)

Wells Regulation – Siting a New Well (technical bulletin)

Wells Regulation – Well Abandonment: How to Plug and Seal a Well (technical bulletin)

Wells Regulation – Well Abandonment: When to Plug and Seal a Well (technical bulletin)

Wells Regulation – Well Disinfection (technical bulletin)

Wells Regulation – Well Repairs and Other Alterations (technical bulletin)


O. Reg. 319/08 Systems

Clean Water Act, 2006

Find Licensed Well Contractors

Guide for Applying for Drinking Water Works Permit Amendments, License Amendments

Laboratories Licensed to Test for Lead

Laboratory Services Notification (LSN) Small Drinking Water Systems Regulation (O.Reg. 319/08)

List of Licensed Laboratories

Notice of Adverse Test Results and Issue Resolution – Small Drinking Water Systems (MOHLTC)

Ontario Water Resources Act, R.S.O. 1990, c. O.40

O. Reg. 169/03: Ontario Drinking Water Quality Standards

O. Reg. 319/08: Small Drinking Water Systems

O. Reg. 387/04: Water Taking and Transfer

Permits to Take Water

Practices for Collection and Handling of Drinking Water Samples

Procedure for Corrective Action for Small Drinking Water Systems that are Not Currently Using Chlorine

Procedure for Disinfection of Drinking Water in Ontario

Report a Spill

R.R.O. 1990, Reg. 903: Wells

Safe Drinking Water Act, 2002

Small Drinking Water System Identification

Small Drinking Water Systems under the Health Protection and Promotion Act – Treatment Options

Small Drinking Water Systems under the Health Protection and Promotion Act – Sampling and Testing

Small Drinking Water Systems under the Health Protection and Promotion Act – Operator Training

Small Drinking Water Systems under the Health Protection and Promotion Act – Responding to Adverse Events

Small Drinking Water Systems under the Health Protection and Promotion Act – Get to Know the Law

Small Drinking Water Systems under the Health Protection and Promotion Act – Source Water

Technical Support Document for Ontario Drinking Water Standards, Objectives and Guidelines

Watermain disinfection procedure

Water Supply Wells: Requirements and Best Practices

Well Regulation – Well Construction Licensing (technical bulletin)

Well Regulation – Well Maintenance (technical bulletin)

Wells Regulation – Completing the New Well’s Structure (technical bulletin)

Wells Regulation – Flowing Wells (technical bulletin)

Wells Regulation – Installing Equipment in a Well (technical bulletin)

Wells Regulation – New Construction of the Hole, Casing, Well Screen and Annular Space (technical bulletin)

Wells Regulation – Siting a New Well (technical bulletin)

Wells Regulation – Well Abandonment: How to Plug and Seal a Well (technical bulletin)

Wells Regulation – Well Abandonment: When to Plug and Seal a Well (technical bulletin)

Wells Regulation – Well Disinfection (technical bulletin)

Wells Regulation – Well Repairs and Other Alterations (technical bulletin)


View these similar posts on the WCWC online library for more information.

Private Wells

First Nations Water System Resources

Small Drinking Water Systems Resources

2021 Annual Reports on Drinking Water in Ontario