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 "I" of the City of Ottawa's Water By-Law, 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, as per the B64.10 Standard.

Properties that pose a severe risk include, but are not limited to, manufacturing and automotive repair facilities, hospitals and dental surgery facilities. Properties that pose a moderate risk include, but are not limited to, 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, as amended.

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 and moderate 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.

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.”

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.”

In January 2018 the City will began notifying affected property owners of the requirement to submit an initial survey. Properties with severe risks will be addressed by December 2020, and properties with moderate risks by December 2022. Notification of all property owners will be complete by the end of 2022.

Severe hazard properties

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.

Moderate hazard properties

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.

Please note:

• Deadlines are based on the date that a property owner receives initial written notification from the City.
• Annual backflow test results for premise isolation assemblies should be filed with Backflow Solutions, Inc. (BSI) Online after results of the Survey of Premise Isolation have been provided, or when the property owner has received an annual testing notice from BSI.
• 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.

Request to extend a deadline for survey submission or device installation

• To request an extension, please complete a request form.

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.

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.
• Pre-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 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 service providers. Properties owners are asked to contact a local plumber and determine if they are certified with the Ontario Water Works Association (OWWA), which can be verified against the OWWA’s tester’s list using the plumber’s full name.

A table defining qualified persons is available in Schedule "I" of City of Ottawa's Water By-Law, 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)
• 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 pre-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.

Step 1: Initial notification letter from City

The property owner receives a letter instructing to survey the affected property.

Please note: The Backflow Prevention Program asks that the property owners receive initial notification before conducting any work on the property.

Step 2: Hire a contractor

The property owner must hire a contractor (a qualified person, as per the City’s Water By-law) to conduct a Survey of Premise Isolation for the affected property.

Step 3: Submit survey results

The contractor (qualified person) submits a Survey of Premise Isolation to the Backflow Prevention Program for review.

Step 4: Review of survey and City’s response

The Backflow Prevention Program reviews the Survey of Premise Isolation. The property owner(s), building contact and the contractor (the qualified person who surveyed the property) receive a response providing at least one of the following instructions:

Notice to Obtain Building Permit

• Apply for a Building Permit through Building Code Services.
• Permit application guidance document [ 245 KB ]
• Contractor (qualified person) to install the appropriate backflow assembly.
• Annual reporting of test results on the installed backflow device(s) (also referred to “assemblies”) to the Backflow Prevention Program will begin one year after the new device is installed, coordinated through Backflow Solutions, Inc. (BSI) Online.

Notice to Repair Existing Device(s)

• Contact Building Code Services to confirm if a Building Permit is required before making any repairs. If required, apply for a Building Permit through Building Code Services.
• A contractor (qualified person) to make the required repairs to the backflow device(s) (also referred to as “assemblies”).
• Repeat Step 3, requiring a contractor (qualified person) to submit a new Survey of Premise Isolation to the Backflow Prevention Program.

Notice to Test Existing Device(s)

• For existing backflow device(s) (also referred to as “assemblies”) from the submitted Survey of Premise Isolation, test results are required to be reported to the Backflow Prevention Program by a qualified tester based on the date provided on the survey.
  • If no date is entered on the Survey of Premise Isolation, reporting of test results for the backflow device(s) will start 60 days from the date of Notice to Test Existing Device(s) letter. Proceed to Step 5.

Step 5: Submitting test results for device(s) to the City of Ottawa

Once the Survey of Premise Isolation has been reviewed and all necessary action has been taken to install and/or repair devices (also referred to as “assemblies”), the City of Ottawa will begin tracking the annual test results of each device (or “assembly”). Testing must be done by a qualified tester and the results must be submitted to the City of Ottawa through Backflow Solutions, Inc. (BSI) Online.

Qualified testers must pre-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.

Request to extend a deadline for survey submission or device installation

• To request an extension, please complete a request form.

Survey of Premise Isolation

On January 1, 2018 the City of Ottawa introduced a Backflow Prevention Program using a premise isolation principle. This program is enabled by the amended Water by-law. The purpose of the program is to prevent the backflow of potentially contaminated water from buildings that are considered severe and moderate hazard risks to the City’s drinking water system. This program also includes backflow assemblies on all building fire protection systems that contain anti-freeze, foam injection, or other chemical additives, connected to a private water supply or where the system poses a hazard to municipal drinking water.

The Property Owner is responsible for ensuring the results of the survey are sent to the City before the deadline indicated in the initial letter of notification.

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. The form must be prepared by a qualified person under Schedule "I" of City of Ottawa's Water By-Law, as amended, and submitted online to the Backflow Prevention Program Coordinator.

Deadlines

• Submit completed surveys within one (1) year from the date of the issuance of the initial letter of notification.
• If required, for buildings designated severe hazard: install an approved premise isolation backflow assembly within two (2) years from the date of the issuance of the initial letter of notification
• For moderate hazard buildings: install an approved premise isolation backflow assembly within three (3) years from the date of the issuance of the initial letter of notification

Contact

Backflow Prevention Program Coordinator
City of Ottawa
Public Works and Environment Services Department
951 Clyde Ave. Ottawa, ON K1Z5A6
Tel: 613-580-2424, extension 22299
Email: backflow@ottawa.ca

Instructions

1. Complete one survey per water metering account.
2. If backflow assembly(s) is installed at the metered water entry(s) into each building, complete one survey per device. In the event premise isolation is achieved by backflow assembly(s) that is installed at the property line, you have the option to submit the survey of premise isolation per property or per building based on the water metering account.
3. Complete all fields unless indicated as optional. If the survey does not adequately accommodate the specific circumstances of your building/campus’s plumbing layout, please provide comments in the Remarks section at the end of the survey, the Program coordinator will contact you.
4. Criteria for assessment of the building’s plumbing layout for premise isolation shall be in accordance with the 2012 Ontario Building Code as amended and CSA B64.10 standard, “Selection and installation of backflow preventers/Maintenance and field testing of backflow preventers”.

The language chosen to complete this form will act as your language of choice for future program correspondence. You may request to change your preferred language at any time by submitting a request to backflow@ottawa.ca.

Survey Guide [PDF]

Complete a Survey of Premise Isolation

Please note:

• For properties with multiple water meters, complete one survey per water meter.
• 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

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.

Annual backflow test results for premise isolation assemblies should be filed with Backflow Solutions, Inc. (BSI) Online after results of the Survey of Premise Isolation have been provided, or when the property owner has received an annual testing notice from BSI Online. A qualified tester can access, complete, and submit a Backflow Assembly Test Form with Backflow Solutions Inc. (BSI) Online.

Please note:

• Qualified testers must pre-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.
• 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.