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Frequently Asked Questions

What prompted this program?
The Ministry of Environment implemented Section 33 of the Safe Drinking Water Act in May 2007. As part of the new framework, Municipal Drinking Water Systems are required to address all risks to the protection of water quality, including the management of the risk of backflow from private water systems into the municipal water supply. Cities across the Province are implementing or already have in place a Backflow Prevention Program to address this requirement and Thunder Bay is now embarking on our implementation. The risk of contaminated water flowing back into the City's water distribution system can be prevented by installing the appropriate backflow devices. The risk of preventing the cross contamination of water within a building can be prevented using proper backflow prevention devices on individual equipment within the building.

What does this program entail?
The program requires that an assessment of the building be performed by a Certified Tester, followed by the installation of the appropriate device(s) by a plumbing contractor licensed with the City of Thunder Bay. Owners and/or their plumbing contractors will be required to obtain plumbing permits to perform this work, and it is through this process that the City's Building Division will administer this program to ensure all buildings are fitted with proper devices within the mandated time line. the installed devices must be tested annually and those result filed with the City (copies to be retained by the building owner and the testing company).

Why do backflow prevention devices require annual testing?
This is a requirement of the CSA Backflow Prevention Standard used right across the Province. They require maintenance, just like your vehicle. Annual testing at the expense of the building owner will confirm that the check valves and mechanics of your devices are working properly and protecting the water supply from contamination.

How much will this cost me?
The cost will vary depending on the complexity of the installation. If the Certified Tester doing the assessment is an employee of a plumbing contractor, it is expected they will be providing an estimate to do the associated work.

What is backflow?
Backflow refers to the reversal of normal flow in a system caused by a negative pressure, or a vacuum in the supply piping. Any plumbing connection between the City's water lines and a private water system is a cross connection, including boilers, hose bibs, and numerous commercial appliances. Similarly, cross connections and backflow can occur within a building.

What is a cross connection?
A potential cross connection can occur as a result of a direct arrangement of pipe lines between a potable and non-potable water system. Boilers, ice making machines, and pop machines are just a few examples of the vast array of possible sources of cross contamination that will be looked at during an assessment to determine if proper cross connection devices are in place.

What causes backflow?
Backflow can be caused by a negative pressure which can be a result of water main breaks, fire hydrant flushing or fire fighting. Back siphonage can draw the water from a private water system. If the water is coming from sources that contain contaminants, such as private boilers, or hoses immersed in solutions containing soaps or chemicals, for instance, the potential exists to contaminate the City water supply. Similarly, this can occur within the building itself. A second type of backflow is back pressure caused by the pressure in a private water system exceeding the City's water system pressure, usually caused by a privately owned pump inside a building causing water to be forced back into the City's system.

Who is required to comply?
Industrial, commercial and institutional (ICI) facilities, along with large multi-residential* properties will be required to install backflow prevention devices. All these facilities will be required to ensure that backflow prevention devices are in place on any cross connection, piping, fixture, fitting, container or appliance that could allow water, waste water, non-potable water or any other liquid, chemical or substance to enter the water system.
*multi-residential buildings - as part of the first phase of this program, which will be approximately 5 years, we are targeting residential buildings greater than 600 m2 or more than 3 storeys in building height.

As a homeowner, does the backflow prevention program apply to me?
Not at this time, but homeowners should be aware of their role in maintaining the integrity of the public drinking water system. Cross connections such as a garden hose with one end immersed in a swimming pool or hoses on laundry tub faucets or lawn irrigation systems are susceptible to instances where that water could be pulled into the drinking water system. There are simple backflow prevention devices widely available at hardware and plumbing stores that can be easily installed onto your exterior hose bibs, laundry tub faucets or as part of a lawn irrigation system.

Who can do an assessment?
Only Certified Testers registered with the City can complete an assessment for cross connections. Currently there are a number of local plumbing contractors who have Certified Testers on staff, and it is expected that more plumbers and professional engineers will obtain certification in the near future to allow them to perform assessments. 

What is the plan for the roll out of the program?
How much time do I have to complete the installation of the required devices?
The City will be identifying properties and letters will be sent from the Development Services Department to identified stakeholders in the ICI and multi-residential sector outlining the Backflow Prevention Program and the specified time frame when those owners must comply. It is expected that this initial phase of the program roll out will require those receiving letters to have their assessments completed with 60 days from that date and allow another 60 days approximately to complete the associated work.

What if the assessment showed that I had an situation that was more complicated than normal?
The results of the assessment of risk for backflow at your business or institution and the complexity of the work required to comply could dictate the amount of time allowed to complete the installation of backflow prevention devices. It is recognized that complicated and expensive backflow prevention undertakings will need to be planned and budgeted for.

Does the City have to comply?
The City is well underway in their process of ensuring that all Corporate structure and facilities comply with the provisions of the Waterworks By-Law.