Backwater Valves

If you’ve ever experienced a flooded basement you know how much damage it can cause, especially if you have a finished basement.

Protect your investment in your home. Call Knight and ask if a backwater valve is a good fit for your property.

Our friendly plumbing experts provide free quotes in full, and we will happily answer any questions you may have.

Let us put our 40+ years of plumbing experience at your service!

5 Stars

Excellent company-we’ve used them 2 times so far and both times very efficient, knowledgeable and quality work.

– Jenn Glover, Calgary

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Backwater Valve Brands

homestar winners 3 years in a row

Mainline Backwater Valves LogoFor rock-solid reliability and value, we love Mainline Fullport backwater valves.

Why You’ll Be Glad You Hired Knight

At Knight, we believe in providing exceptional service:

  1. We arrive on time.
  2. We look presentable and behave professionally.
  3. Multi-award winning service.
  4. Guaranteed workmanship – if you’re not happy we’re not done.
  5. 2-year labour warranty and 1 year parts warranty.
  6. We clean up our work area when we’re done.
  7. Seniors get a 5% discount.

Best of all, you’ll appreciate our neighbourly approach to serving you – there’s no pressure or hard sell tactics of any kind. You’ll get the information you need to make a smart decision.

Ready to book your appointment?

Call 403-287-8980

Backwater Valve FAQ

backwater valve diagram
Diagram of Mainline’s Fullport backwater valve, which we recommend.

1. So what’s a backwater valve anyway?

A backwater valve ensures that sewage can’t flow from the city sewers into your house. If the city sewers in your area get clogged or overflow, a stopper will close and prevent any sludge from backing up into your home.

2. My house is on higher ground. That means I don’t need a backwater valve, right?

Not necessarily. It’s all about how full the sewers are in your area, and if your home is situated above the grade of the main sewer system.

when backwater valves needed

3. Will a backwater valve prevent all flooding?

Unfortunately nothing can guarantee that you’ll never experience a flood. If one of our rivers overflows its banks and there’s water over the surface of the ground, no valve can stop that. It also cannot prevent clogs inside your home. A backwater valve does one job perfectly: it prevents flooding due to overloaded sewers.

4. Can a backwater valve be installed on any home?

Technically yes, but ideally the drainage slope of your home’s sewer line needs to be at least ¼” per foot. Otherwise you may need to flush it out once a week. For some people, it’s worth it to avoid ever having to deal with a basement full of sewage. We will do an assessment and let you know what the pros and cons of your individual situation are.

5. Do backwater valves need any maintenance?

A periodic look through the window on the top should tell you if the valve has floated or not (if it’s spring or there’s lots of heavy rain you should check daily). If the valve has floated it means the level of water in the sewer is high. You will need to stop using your water and toilets and call us.

6. How much do backwater valves cost?

The units themselves are not that expensive. It’s the installation that needs to be done with care.

Also, sometimes you need more than one. In older neighbourhoods (pre-1960s) the sewage and storm drains are the same, and one backwater valve will work. In newer areas with separate storm and sewage lines, you may need two.

No matter what the final cost is, rest assured we will provide the full quote in advance so you can decide. The quote will include all labour fees – you won’t pay a cent more.

If you need more information or want to know if a backwater valve is right for you, ask for your free quote.

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