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Backflow Prevention Program

About the Backflow Prevention Program

The City of Ottawa’s Backflow Prevention Program protects drinking water quality by ensuring the appropriate installation and inspection of devices that prevent contaminated water from flowing back into the City’s water distribution system, as required under Schedule H of City of Ottawa Water By-Law 2013-360, as amended. The program supports compliance with the highest industry drinking water protection standards to ensure public safety and the long-term safety of our shared water resource.

Backflow prevention programs are currently in place in numerous Ontario municipalities, including Toronto, Hamilton, London, Markham, Halton Region and Waterloo.

The Backflow Prevention Program Report was approved by Council on June 28, 2017.

Who is affected?

While the Backflow Prevention Program will not apply to the majority of City drinking water customers, it will impact approximately 15,000 industrial, commercial, institutional and multi-residential properties classified as severe or moderate risk for backflow incidents.

Properties that pose a severe risk include manufacturing and automotive facilities, hospitals and dental clinics. Properties that pose a moderate risk include apartments, hotels, motels and schools. The program will address moderate risks from multi-residential buildings that are over three stories or have a footprint over 600 m2 (or 6,458 ft2).

Standards and regulations

The standards for backflow prevention are established in the Canadian Standards Association (CSA) Manual for the Selection and Installation of Backflow Preventers/Maintenance and Field Testing of Backflow Preventers (CSA B64.10) and the Ontario Building Code.

The program will require premise isolation (the separation of a property's private water system from the City's drinking water supply) for all severe and moderate service connections through the installation of premise backflow devices in accordance with CSA standards.

CSA standards define severe, moderate and low hazard to drinking water systems:

  • Severe hazard: Any connection or potential connection that involves water that has additives or substances that, under any concentration, can create a danger to health.
  • Moderate hazard: Has a low probability of becoming a “severe hazard.” The water’s aesthetic qualities have been further reduced, and under certain conditions, may create a danger to health.
  • Low hazard: Any connection or potential connection that involves a substance, which has reduced the water’s aesthetic quality, this could involve water that has been heated or cooled. Generally, these hazards are a nuisance only, and upon consumption pose no danger to health.

What is backflow?

Typically, drinking water flows from the City’s distribution system into a property’s private water system. Backflow is the undesired reversal of water flow between the City's distribution system and a private system, due to changes in water pressure. This reversal or “backflow” can cause contaminants to enter into the drinking water distribution system.

Causes of backflow

Backflow can occur due to back siphonage or back pressure.

  • Back pressure occurs when pressure in a private water system is greater than pressure in the City’s water supply system, which may be caused by pumps, elevated tanks, temperature increases in boiler systems, and other local pressure events. This can result in water from the private system forcing its way into the City’s distribution system.
  • Back siphonage occurs when pressure in the City’s water supply system is lower than pressure in a private system, which may be caused by nearby fire-fighting or water main breaks. This reversal of pressure can pull contaminated water from the private water system into the City’s distribution system.

Types of backflow devices

There are two types of backflow prevention devices (or assemblies) common in achieving premise isolation:

Double Check Valve Assembly (DCVA): Consists of two check valves, which help to provide protection in the event that one valve does not close tightly. Required for facilities classified as “moderate hazard.”

Double Check Valve Assembly showing two check valves.

Reduced Pressure Principle Assembly (RP): Consists of two independently acting, internally loaded check valves, separated by a reduced pressure zone. Required for facilities classified as “severe hazard.”

Reduced Pressure Principle Assembly showing two internally loaded check valves.

Timelines for program compliance

In January 2018 the City will begin notifying affected property owners of the requirement to submit an initial survey.

Owners of severe hazard properties have one year to complete a site survey and an additional year to install backflow devices.

  • For example: An owner of a severe risk property notified in January 2018 will need to complete a site survey by January 2019 and install a device by January 2020.

Owners of moderate hazard properties have one year to complete a site survey and two years to install backflow devices.

  • For example: An owner of a moderate risk property notified in January 2021 will need to complete a site survey by January 2022 and install a device by January 2024.

Properties with severe risks will be addressed by December 2020, and properties with moderate risks by December 2025. Notification of all property owners will be complete by the end of 2022.

Please note:

  • Deadlines are based on the date that a property owner receives initial written notification from the City.
  • Property owners with existing devices and test data are encouraged to submit their most recent information to Backflow Solutions Inc. (BSI) Online.
  • Backflow devices must be tested at the time of installation and annually. Property owners will receive a reminder of their annual testing deadline 30 days in advance.

Exceptional circumstances

  • Owners of moderate risk properties that require a significant investment in backflow device installations may request additional time to complete the work. Submit a plan by the site survey deadline for review and approval, providing a rationale for the request and demonstrating how installations will be complete by 2027.
  • Properties scheduled for demolition within the implementation timelines may be exempt from the requirements. Submit a demolition plan by the site survey deadline for review and approval.

Roles and responsibilities

Responsibilities of the property owner

Between 2018 and 2027, based on severity of the hazard, all affected property owners will be required to hire a qualified person to:

  • Conduct site surveys every five years to identify risks and report backflow prevention requirements to the City for review. Property owners will receive a reminder to submit an updated survey prior to the deadline.
  • Install premise isolation backflow devices to prevent contaminants from entering the City’s water supply.
  • Test backflow devices every year to make sure that they are functioning properly and submit the test results to the City for review. Property owners will receive a reminder of their annual testing deadline 30 days in advance.  

Property owners must notify the City within 30 days of any change in hazard level. This could be due to a change in building operations or activities, or any changes in the service connection to the building or property.

Responsibilities of backflow device testers

Testers who have successfully completed the required training with an accredited organization and have a current tester’s certificate will:

  • Maintain a current tester’s certificate.
  • Register with Backflow Solutions, Inc. (BSI) Online to provide information on qualifications and submit annual calibration test data for testing equipment.
  • Submit site surveys and test results on behalf of an owner.
  • Collect tester and administration fees and submit administration fees to the City of Ottawa.

Responsibilities of the City of Ottawa

The City is responsible for administering the program and complying with the program as a property owner. The City will:

  • Oversee administration of the program.
  • Inform property owners about the program and their responsibilities.
  • Send notifications on site survey and testing requirements.
  • Allow testers to register and submit test results on behalf of owners.
  • Provide access to owners to be able to review their test data.
  • Track the City’s backflow device assets for maintenance and other purposes.
  • Collect City administration fees from testers.

Qualifications for surveyors, installers, and testers

Qualifications and training needed to conduct site surveys, install backflow devices and test devices are established in the Canadian Standards Association (CSA) B64.10 standards.

The City does not provide a list of approved services providers. The Ontario Water Works Association (OWWA) maintains a list of certified testers.

A table defining qualified persons is available in Schedule H of the City of Ottawa Water By-Law 2013-360, as amended.

Site surveyor qualifications

A qualified site surveyor is a:

  • Certified Cross Connection Control Specialist as per the Ontario Water Works Association (OWWA), and
    • Licensed master plumber, or
    • Journeyman plumber, employed by a licensed plumbing contractor
  • Professional engineer
  • Certified engineering technologist under the direction of a professional engineer.

Installer qualifications

A qualified person to install, relocate or replace a backflow prevention device is a:

  • Certified Cross Connection Control Specialist as per the Ontario Water Works Association, and 
    • Licensed master plumber, or Journeyman plumber, employed by a licensed plumbing contractor; or 
    • Apprentice plumber, employed by a licensed plumbing contractor and under supervision of a journeyman plumber or master plumber; or
    • Industrial millwright licensed by the Ministry of Environment and Climate Change (MOECC) as a Water or Wastewater Operator. Industrial millwrights who are licensed by the MOECC as a Water or Wastewater Operator can install, replace, test and repair devices for water and wastewater systems.

Tester qualifications

A qualified person to test and repair a backflow device is a:

  • Certified Cross Connection Control Specialist as per the Ontario Water Works Association, and at least one of the following:
    • Professional engineer
    • Certified engineering technologist under the direction of a professional engineer  
    • Licensed master plumber
    • Journeyman plumber, employed by a licensed plumbing contractor
    • Apprentice plumber, employed by a licensed plumbing contractor and under supervision of a journeyman plumber or master plumber
    • Industrial millwright (industrial millwrights can test devices, but not repair them)
    • Industrial millwright licensed by the MOECC as a Water or Wastewater Operator
    • Fire system sprinkler fitter (for fire protection systems)
    • Irrigation system installer (for lawn sprinkler systems)
  • Backflow device testers also need a current calibration certification through the National Institute for Standardization Technology for the test equipment to be used.
  • Qualified testers must register with Backflow Solutions, Inc. (BSI) Online and provide information on qualifications. Testers are also required to submit annual calibration test data for testing equipment.

Survey and testing forms

Survey of Premise Isolation Form

To receive a copy of the program’s Survey of Premise Isolation Form, please contact the Backflow Prevention Program Coordinator at backflow@ottawa.ca.

The form must be prepared by a qualified person under Schedule H of the City of Ottawa Water By-Law 2013-360, as amended, and submitted to the Backflow Prevention Program Coordinator.

Please note:

  • The City will notify property owners when a site survey is required. Surveys must be updated every five years, or within 30 days of any hazard level increase.
  • For properties with multiple buildings under a single civic address, complete one survey for each building.
  • If a completed survey indicates the requirement for the installation of a new backflow device, replacement of a defective device or the relocation of an existing device, obtain a building permit prior to the commencement of any work. Please review Building Code Services’ information on permit application requirements.

Backflow Assembly Test Form

A qualified tester can access, complete, and submit a Backflow Assembly Test Form with Backflow Solutions Inc. (BSI) Online.

Qualified testers must register with BSI Online and provide information on qualifications. Testers are also required to submit annual calibration test data for testing equipment.

Please note:

  • Backflow devices must be tested at the time of installation and annually. Property owners will receive a reminder of their annual testing deadline 30 days in advance.
  • Property owners with existing devices and test data are encouraged to submit their most recent information to BSI Online.
  • The maintenance and testing of devices must follow the Canadian Standards Association (CSA) Manual for the Selection and Installation of Backflow Preventers/Maintenance and Field Testing of Backflow Preventers (CSA B64.10) and the Ontario Building Code.

Program costs

The Backflow Prevention Program will operate on a 100 per cent cost recovery model. No financial assistance is available to achieve program compliance.

To ensure cost recovery, property owners will pay a $53 administration fee when a qualified person submit test results on their behalf.

Property owners will pay qualified service providers to conduct site surveys, install, maintain and repair premise isolation backflow devices and test the devices yearly. The cost will range from $500 to $100,000, depending on the size of the water service line and the need for structural work as part of the installation.

Building Code Services administration costs include an $80 building permit fee.

Enforcement

If a property owner does not comply within the indicated timelines, a notice of violation will be issued, providing 30 days to conduct a site survey, install or test the backflow prevention device(s) and submit the required documentation. If the owner does not comply, they can be charged under the Provincial Offences Act with a fine ranging from $500 to $100,000 per day, or their water supply can be turned off.

Contact the Backflow Prevention Program

If you have any questions or require further information, please contact the Backflow Prevention Program Coordinator at backflow@ottawa.ca.