July 8th, 2013 is a day that many Torontonians and people living in the GTA will not soon forget. A torrential downpour of 100 millimetres of rain according to Environment Canada trounced the previous one-day rainfall record leaving many with out power, crippled commuters, and for many homeowners left their basements a flooded soggy mess. In the days that followed the storm every single news outlet in the region was showing homeowners starting the remediation process by cleaning up and throwing out everything that occupied their basements. Valuables and memories destroyed.

Flooded Basement

Could this have been prevented? Well, of course. The better question is why did this damage happen to so many basements in the GTA? That answer is quite simple and is partially two fold. Some homeowners suffered basement flooding because their home’s foundation was just not adequately waterproofed, but for the vast majority of those affected during this record storm this was not the case. What caused basement flooding was something that is becoming an increasing occurrence in the City of Toronto and which homeowners can easily prevent. Basement flooding struck when the storm sewers that all your drains from your home flow out to flooded forcing water back from the city sewer pipes through your home’s main drain and up through your basement’s shower drains, toilets, and sinks. To further makes things worse not only do you now have a flooded basement that is sure to start the birth of mold, but also you have been flooded out with waste water, not ground water. Waste water is very dirty containing bacteria and other undesirable ingredients. It’s sewage water. Gross! So what exactly can help a homeowner prevent against this very costly and degusting problem, very simple. A back water preventer valve also referred to as a back water valve, or back water preventer can be easily installed.

Simply put, a back water preventer valve automatically senses a reverse flow in the main drain pipeleading to the city’s sewer pipes and completely closes the line when the condition occurs leading to zero waste water entering your home. Here is an illustration of how the back water preventer valve works.

The city of Toronto took notice of this problem a few years ago and has since instituted a program to help subsidize homeowners with the cost of installing a back water preventer valve. The program is called the Basement Flooding Protection Subsidy Program. More detailed information is available by clicking here. Basically if you meet a certain criteria, which most homeowners do, the City of Toronto will rebate a good portion of the total cost of installtion. The program also offers rebates for adding a sump pump and/or disconnection your down spouts from the city’s sewer system.


If you have any questions regarding the back water preventer valve, a sump pump, or a downspout disconnect please feel free to contact us. We can assist you with better understanding Basement Flooding Protection Subsidy Program and help you get the necessary rebate. 

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