• Geoff Burke

How To Prevent Another Flooded Basement



Hello again everyone – welcome to another episode of “How NOT to Call the Plumber!”.


OK, we need to get real this week. After the heavy rain Tuesday to Thursday, we received A TON of calls for flooding in the basement. For many of you, my post last weekend was like a glimpse into what happened just a few days later (take a look if you didn’t see it last week!). So, let’s go through a few things you can do to stop this from happening to you. PLEASE take them seriously!


The first and most important thing you can do to prevent a sewer backup during a big storm is to disconnect your downspouts from the sewer system. In older homes, plumbing was done using what is called a “Combined” sewer system. This simply means that both the sanitary and storm sewers meet in a larger pipe under your basement floor, which then transports both the rain and wastewater out to the city sewer. There is a problem with this. If you happen to have even a partial blockage in that pipe under your basement floor, the amount of water rushing through that pipe during a storm will often overwhelm it, showing up as a backup in the basement (hence why you don’t often see older homes with finished basements). Aside from it just being a good thing to do to prevent a flood in the basement, the City of Toronto has also mandated that the disconnection of these downspouts is done by each homeowner!


The second thing you can do to prevent a sewer backup in the home is to install a backwater valve. I know I’ve nagged you about this before, but it is a very important thing to have. Backwater valves work to prevent flooding caused by an issue anywhere “downstream” of the very front of your home. A Backwater valve works on a very simple process; there is a “flap” inside of the pipe that recognizes when the water starts to back up and closes itself until that backup subsides. The thing with backwater valves is that the more people who have them installed, the more important it is for you to have one as well.


Let’s play through a small situation here. You’re talking to your neighbours on either side of you, and as luck would have it, they’ve both had backwater valves installed. Unfortunately, you haven’t been able to get around to it yet (let’s be honest, spending money on a backwater valve isn’t as exciting as repainting the house or putting in new countertops). A week later, a storm rolls through and you have a flood in your basement. Here’s the issue: since both of your neighbours have backwater valves that stopped water going into their basements, any of the water that would have been evenly dispersed through all of your basements is now only directed into yours! As you can likely see, backwater valves are a very important part in protecting your plumbing system.


Lastly, the installation of a sump pump is a good way to mitigate the effects of rising groundwater underneath the foundation of the house. Simply put, a sump system would take that rising water, direct it into a pit, and pump it out of the house far enough away from the foundation that we wouldn’t worry about it just cycling back again. If you do already have a sump pump installed, it typically has a 7 year lifespan, so keep that in mind!


Now, these things can be expensive. But there are a couple of ways that can make this more of a reality. First, the City of Toronto still has a great rebate program for this type of work. For backwater valves and sump pumps, you will receive rebates of $1250 or $1750 respectively (or 80% of the total invoiced cost). Also, some plumbing companies will offer financing at reasonable rates to help in a situation where you may not want or be able to shell out the full amount at that time. These financing terms are often quite flexible, so you can tailor the payments as needed.

That’s it for this week! I’m sorry to have nagged you again, but I will keep doing it until I never get a flooded basement call again! 😊. I hope you all have a wonderful week and we’ll see you next time.

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