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What Is a Backwater Valve and Why Do you Need one?

When the reporters on the news warn viewers of a torrential downpour, the average homeowner makes small preparations to avoid any damages. They put away the furniture sitting on their porch or their back patio and store it safely in the garage. They shut their windows and doors tightly so that the rain can’t blow inside. If the winds are predicted to be at breakneck speed, they decide to stay indoors and hold down the fort until the storm clears.

The one spot that a lot of residents don’t think about when the rain starts to come down in sheets is their basement. When the municipal sewer system gets overwhelmed with the sudden rush of water, it sends the contents back into home plumbing systems. Homeowners will be too busy worrying about the shower drenching everything outside their front doorstep, that they won’t realize that their basement is filling with sewer water. The only way to protect your home against this frustrating problem is to get a backwater valve installed.

backwater valve

Why do Torontonians need to worry about rainstorms?

Sudden downpours that overwhelm the municipal sewage system are not a weekly problem, but they happen enough that residents should be concerned about them. The influence of climate change has made weather patterns extreme, so there is a high probability of storms growing more frequent and severe in nature. There will be another storm that overruns the city for a few hours and leaves a serious mess to clean up in the future.

One of the factors that contribute to the city floods is called urban run-off — this is when rainwater collects in urbanized spaces because there are so many paved surfaces. When there is a heavy storm in a rural area, the rainwater can’t collect as easily because it can be directly absorbed by the soil.

City streets, sidewalks, parking lots and structures can’t absorb the falling water. The impenetrable surfaces collect the water and let it pool, making the lowest areas in the city flood. All of the run-offs plunges into the Toronto sewers at once, which inevitably causes water to spill out of manholes and back-up into basements.

Another important reason why Toronto flooding should be a growing concern is that the sewer system is not equipped to handle excessive amounts of stormwater in such a short period of time. In the summer, the interim deputy city manager compared the system to a bathtub that fills up and spills over when the water comes out of the tap too quickly.

Certain infrastructure changes could reduce the impact of city-wide floods, but they are expensive and difficult for the government to implement. The good news is that homeowners have the opportunity to be eligible for a flood protection subsidy program worth a maximum of $3400 per property if they get a sump pump, sever and cap a storm sewer/weeping tile connection and get a backwater valve installation in Toronto.

Homeowners that live in Markham can also benefit from the city’s private plumbing protection rebate program when they get weeping tile disconnected, get a sump pump, get sanitary/storm laterals repaired and get a backwater valve installed. Residents who have already completed these plumbing improvements may be eligible for retroactive rebates.

What is a backwater valve?

A house’s plumbing system is connected to the city’s sewer system by the main line. The water and excrement from bathtubs, showers, sinks and floor drains travel down the main line to get to the public sewer. Since the main line is an open channel, it’s possible for the sewage to be pushed back up the line and through the drains located on the lowest level of the house.

This scenario can happen when there is a sudden storm and the public sewers are overwhelmed with water. It can happen when there is a large obstruction in the public sewer that stops the regular flow of water, pushing it up toward manhole covers, grates and personal plumbing systems. Finally, the scenario can also happen when there is a lot of water in the public system and street-level openings are clogged.

Sewer grates and manhole covers are supposed to let excess water spill onto the street. When they are clogged or covered, the sewer water needs to find other areas to escape — this is often the nearest personal main lines. The obstructions of public sewer openings are often caused by outdoor debris like dead leaves and branches.

As protection against situations of public sewer back-flow, a backwater valve is installed inside a house’s main line so that the pipe doesn’t act like a two-way passage anymore. It becomes a one-way passage that only lets drained waste exit from the house and into the public sewer system. The valve contains a flap that will not let any flow of water move upwards — this way, water and waste can leave, but it cannot come back. This is the most effective solution for preventing this specific plumbing issue.

You should protect yourself with a backwater valve if you have dealt with damage from a sewer back-up in the past because your house is susceptible to this type of flooding. If it’s happened before, it’s likely to happen all over again.

Toronto residents that live in areas prone to flooding should also think about guarding their properties against any severe storms down the line with new backwater valves. Spots that are low-lying will have more trouble than those that are higher topographically because water will pool at the lowest points. Living in close proximity to bodies of water like rivers, lakes and ravines also puts you in a precarious position.

Here are some neighbourhoods and areas that the Toronto Region Conservation Authority has marked as vulnerable to flooding on their map of the Greater Toronto Area:

  • South Mimico
  • Jane/Wilson
  • Brickworks
  • Lower Don Valley
  • Albion Road
  • Markham Industrial

If you’re worried about the expense of this plumbing solution, you can apply to your city’s subsidy or rebate program. If that’s not enough, you should check out our latest promotions on our website so that you can save some money on your upcoming plumbing renovation or repair. One of the coupons slashes $200 from the costs of a backwater valve installation. It’s also important to think of the purchase as an investment for your home. The initial cost may seem like a lot at first, but it’s small in comparison to the costs of water damage.

 What are other steps for flood prevention?

A backwater valve can protect you against sewer back-up, but it won’t save your basement from other forms of flooding. If a pipe bursts or a fixture overflows, you will need other plumbing solutions to stop the water from pooling and to limit the damage. You can install a sump pump in the lowest part of your basement to pump out collecting water and divert it away from the house. This is an excellent tool for keeping the basement dry, especially if your floor drain isn’t working as it should.

Another good way to prevent a flood is to keep your plumbing in top condition. Make sure that your drains are clear of any clogs on the inside or covers on the outside. A clear floor drain can be helpful for preventing a basement flood, but a clogged one will make the circumstances worse.

Insulate your pipes when the weather is cold and have a professional thaw them out if they freeze. Ignoring this winterizing tip could lead to a burst pipe and water pouring everywhere. If you suspect you have a leaking or cracking pipes, get them fixed or replaced before they collapse. As a preventative measure, you can call us for your drain repair needs and your drain clearing needs so that your house doesn’t fall victim to an unexpected flood.

 You can always call a 24-hour emergency plumber in Toronto if worse comes to worst and you walk downstairs and see that you have a small lake forming on your basement floor. We understand that these types of disasters don’t happen at a convenient time, so you can call on the weekends or holidays when every other business is closed. Whether it’s first thing in the morning or the middle of the night, we will send experts to your front door right away. When you don’t have any plumbing protections put in place, a quick response can limit any of the damage caused by a flood.

Homeowners don’t just have rainstorms to worry about during the summer and fall — sewer back-up can also happen during the late winter and early spring. When the snow and ice melt all at once, it can send too much water into the public sewer system. The chances of this happening grow if the weather is warm enough to send rain showering down at the same time.

The disruptive phenomenon is called spring thaw flooding, and it can surprise residents just as much as summer storms. When you get a back-water valve installed, you guard your home against an expensive and disgusting mess all year round.

backwater valve

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