Backflow explained
What is a backflow preventer, and why does it need testing?
A backflow preventer is a device that stops water from flowing backward out of your building and into the City's clean drinking water. Commercial buildings are equipped with backflow devices to prevent the mixing of potable and non potable water, and those devices are required to be tested by a certified tester every year. A device can look fine and still fail, so the only way to know it works is to test it. Norm's has certified backflow testers on our team, and we're on the City of Nanaimo's list of local companies with certified testers.
Got a testing notice from the City?
- Book a certified tester
- We test the device
- The tester sends the report to the City
- If it fails, we repair it and retest
Don't let a City notice sit. Call 250-753-3641 and we'll book your test.
How it works
How your backflow test works.
- Book
Call or email us with the address and, if you have it, the City notice or last year's test report.
- Test
A certified tester from our team inspects and tests the device on site.
- Report
The City requires the certified tester who did the test to submit the report, so that's handled for you.
- Fix if needed
If the device fails, we explain what's wrong, repair or replace it, and test it again.
City of Nanaimo rules
What does the City of Nanaimo require for backflow testing?
Nanaimo's Cross Connection Control Bylaw (Bylaw 7249) says the owner or occupant must have an approved backflow prevention assembly inspected and tested by a backflow assembly tester when it's installed, after a repair, and at least once in every 12 month period after that, at the owner's expense. The City also says owners must make sure the tester they hire holds a current BCWWA Backflow Assembly Tester certification. Checked October 21, 2026. Rules change, and we confirm them at your quote.
Under Bylaw 7249
- Test on installation, after repairs, and at least every 12 months
- A test report is due within 30 days of installing, repairing or moving a device
- If you get a notice to test, the City can set a 30 day deadline
- A failed device must be repaired and retested
- Removing a device without replacing it needs the City's written consent first
Test reports
How do my backflow test results get to the City?
The City of Nanaimo says test reports must be submitted by the certified tester who inspected and tested the assembly. The report records the install and test date, where the device is, its manufacturer, model, size and serial number, and confirms it's an approved assembly that's installed correctly and working. You don't have to fill out the City's form yourself. Checked October 21, 2026. Rules change, and we confirm them at your quote.
Commercial buildings
Who needs a backflow test every year?
Most often it's businesses, commercial buildings, stratas and other facilities with a backflow device on their water service. The City says the owner of the business or facility is responsible for installing, maintaining and renewing any required backflow device. We look after backflow testing as part of our commercial building maintenance, along with drain stack cleaning, plumbing and heating and cooling, so one company can handle your yearly building services.
What we do
- Annual backflow testing by a certified tester
- Backflow device repair and replacement
- Testing after a new install or repair
- Maintenance agreements for buildings and stratas
Irrigation
Does my irrigation system need a backflow test?
If it has a required backflow device, yes. Under Bylaw 7249, anyone operating a commercial or agricultural irrigation system must have the backflow assembly inspected and tested by a backflow assembly tester before the system starts up each irrigation season. Where fertilizers, chemicals or anything else harmful to health is added to an irrigation system, the bylaw requires a reduced pressure principle backflow assembly. The City's homeowner brochure also lists irrigation systems, garden hoses, pools and hot tubs, boilers and fire sprinkler systems as common cross connection risks at home. Checked October 21, 2026. Rules change, and we confirm them at your quote.
At home
Can a house have a backflow problem?
Yes. A cross connection is any place where clean drinking water can mix with something that could contaminate it. If water pressure drops, during a water main break, firefighting or heavy water use, contaminated water can be pulled backward into your pipes. The City's tips: don't leave the end of a garden hose sitting in a bucket, pool or hot tub, remove a hose from a fertilizer or weed killer sprayer right after use, and keep shower hoses out of the bathwater. During plumbing work, a qualified plumber may find that your property needs a backflow device.
Common risks at home
- Garden hoses
- Irrigation systems
- Pools and hot tubs
- Boilers and heating systems
- Fire sprinkler systems
Closed systems
Why does a backflow device matter for my hot water tank?
A backflow preventer or pressure reducing valve stops water from flowing back into the City system, which makes your plumbing a closed loop. When water heats up it expands, and in a closed system that pressure has nowhere to go. Over time it can damage pipes, fittings and the water heater itself. That's why an expansion tank is often required by code when a backflow preventer is installed. We check for it when we test or install a device.
Our testers
Who does the testing at Norm's?
Doug Harty, a Red Seal Plumber at Norm's, is one of our certified backflow testers. Being on the City's tester list isn't an endorsement by the City, and the City asks owners to check that a tester's certification is current, so ask us and we'll confirm it before the test.
Why Norm's
A test done right, and on file.
Backflow testing is done by certified testers on our own team.
The certified tester submits your test report to the City.
If a device fails, our licensed plumbers repair or replace it and retest.
A third-generation Nanaimo family business, serving the Mid-Island for more than 50 years.
We called Norm's Plumbing because we heard from community members that they are dependable. We called, set up a time and day, and they showed when they said they would. Graham was proficient, explanatory, focused, went above and beyond, and was incredibly kind. We will always call Norm's, and happy to recommend to anyone who needs their support and service!
A+ experience. I've only used Norm's Plumbing and Heating since purchasing my home and everything has been fine. Just call them, they know what to do. I've seen the same faces, very little employee turn around it seems. Happy workers too?
What it costs
What does a backflow test cost?
It depends on the number and type of devices and whether anything needs repair. We give you the price before we test. For buildings with several yearly services, we can set up a maintenance agreement so backflow testing, drain stack cleaning and heating and cooling maintenance come as one package.
- Price confirmed before the test
- Repairs quoted before we do them
- Packaged pricing for commercial buildings
FAQ
Backflow testing questions, answered
How often does a backflow preventer need to be tested in Nanaimo?
At least once every 12 months, plus when it's installed and after any repair, under the City's Cross Connection Control Bylaw 7249. The City can require more frequent testing in some cases.
Who can test a backflow preventer?
A certified backflow assembly tester. The City of Nanaimo asks owners to make sure the tester holds a current BCWWA Backflow Assembly Tester certification.
Is Norm's on the City of Nanaimo backflow tester list?
Yes. Norm's Plumbing, Heating & Air Conditioning is on the City's list of local companies with certified backflow testers. The City notes the list isn't an endorsement.
Who sends the test report to the City?
The certified tester who did the test. The City requires the report to come from them, so you don't need to send it yourself.
What happens if my backflow device fails?
It has to be repaired and tested again. We explain what failed, give you the price, repair or replace the device and retest it.
I got a notice from the City to test my backflow device. What do I do?
Book a certified tester right away. The City can set a deadline, often 30 days, in the notice. Call 250-753-3641 and we'll get you booked.
Can I remove a backflow preventer I don't think I need?
Not on your own. Under Bylaw 7249, removing a backflow preventer without replacing it needs the City's written consent first, and the City has a removal report for it.
Do you test irrigation backflow devices?
Yes. Commercial and agricultural irrigation systems need their backflow assembly tested before start up each season under the City bylaw. Call us before you turn the system on.
Related services
Ready when you are
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