How To Protect Your Basement From Sewer Back Up Flooding.

 

Sewer Backup

Sewer Backup

Having lived through a sewer back up in my basement last year, the one thing you do not want is to repeat this hellish experience.  I think we all agree that Toronto thunderstorms have become much more intense and violent from what they were just a decade ago.   With 80 to 120ml of rain falling within a 2 hour period our aging storm and sewer systems were never built to handle this massive amount of water.  So when neighbourhood streets turn into rivers, it’s a sure sign that this excess water is looking for a place to go and our basements are the perfect receptacle.  Rain and raw sewage is not a pretty sight for any homeowner.

Presently the only secure way to avoid sewer backup is to install a flow prevention valve, which some call a back flow valve. 

What’s Their Function?

How a backflow prevention valve works

How a backflow prevention valve works

With every single shower or toilet flush our waste water is cleanly and efficiently removed from our house and sent out to the middle of the street to the sewer system.  This is a one-way system and for 99% of the time it works flawlessly.  However when the sewer system has over-reached its maximum capacity then the tides turn and it now becomes a foul and toxic flow moving  back into your home.  The flow prevention value is an add-on installation which functions exactly at the time when sewer system is backing up and flowing into your home.  It is a mechanical device which engages when the flow is reversed and moving back into your house. It is basically is a hinged flange which floats up to cut the back flow, therefore isolating your home’s sewer system from the neighbourhood grid.   With the flow unable to enter your home this toxic soup will look for another home, most likely your neighbour without a flow prevention valve to dump the overload.

Types of Flow Prevention Valves

There are two types of residential flow prevention valves:

  • One which is built inside in home’s basement
  • The other is built into your exterior sewer clean-up access

The back flow prevention valve which is installed in your basement is the cheaper of the two options.   Expect to pay approximately $2,000 plus HST to have a plumber complete the work.    What is required is to dig out part of your basement to access your home’s sewer line, install the back flow prevention valve and then build a permanent service hatch.

Interior Backflow With Hatch

Interior Backflow With Hatch

Now the have a back flow prevention values installed as part of your exterior sewer access expect to pay around $2,800 plus HST.  The work required is to dig down approximately 6- 8 feet to access your sewer line, install the back flow prevention,  attach a new sewer access line and then refill the hole.    It does cost more, but you don’t have to have your basement floor ripped up and then you don’t have to concern yourself regarding the permanent serve hatch.

 

The good news is that the City of Toronto is still offering homeowners a rebate of $1,250 to offset the cost of the work.     Considering the increase in costs incurred by the insurance companies in settling claims, they are presently discussing with the city to make these valves mandatory.  My suggestion is to get the work done now while the rebate program is active.     We all know that as the city looks for cost savings this $1,250 may not be around during the next Toronto budget talks.