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Skip Navigation LinksSSBWV-Program Sanitary Sewer Backwater Valve Subsidy Program
Skip Navigation LinksMidland > Sanitary Sewer Backwater Valve Subsidy Program


Sanitary Sewer Backwater Valve Subsidy Program

The impact of climate change continues to present an unprecedented challenge to municipal infrastructure given both the intensity and severity of current storm events.  The implications of climate change are placing greater challenges upon local municipal infrastructure budgets, both operating and capital. The Town has been engaged in a program of replacing combined sanitary sewer and stormwater systems through the allocation of the annual capital budget program. 

Due to the Town's limited financial capacity, replacement efforts will take many years to complete the upgrades. This concern has prompted the Town to create a backflow prevention subsidy program aimed at assisting homeowners to take reasonable steps to prevent flooding events before the municipality is able to replace the combined sewer and stormwater infrastructure. it is essential that homeowners take the appropriate action to reduce the risk of basement flooding on their own private property.  Homeowners may be able to reduce the impact by installing a backflow prevention device on their sanitary sewer system.

Why should I install a backwater valve?

Installing a backwater valve can help decrease the incidence of basement flooding by reducing the risk of wastewater from entering your home. Basement flooding can happen during a severe weather event or if the Town's wastewater system reaches its maximum capacity.​

What is a backwater valve and how does a backwater valve work?

A backwater valve is a type of check valve that is designed to only allow flow in one direction.  Different valves work in different ways, but in general, the type of device used in sanitary sewer scenarios works like this:

  • The valve is normally in an open position: the gate or flap is open

  • When a backflow event occurs, floats under the gate lift up and start to block the backflow

  • If the backflow event increases, the gate closes against a gasket and creates a seal which does not allow wastewater to pass in the backwards direction

  • When the backflow events ends, the gate falls back down due to gravity and returns to the open position to allow normal outflow of wastewater from the home's plumbing system


Contact Natalie Murdock
nmurdock@midland.ca or 705-526-4275 ext. 2217

 More FAQs

Does the Town provide a subsidy?

​Yes. The available subsidy is 80% of the invoiced cost, to a maximum of $900.​

Does the subsidy apply to homes that are currently under construction?

​Eligibility requirements our outlined in the Town's Sanitary Sewer Backwater Valve Subsidy Policy​.

Does the Town recommend a contractor/plumber to perform the work?

No. It is up to the homeowner to research and hire a certified/licensed plumber to complete the work.

How do I know if the contractor/plumber is certified?

​The certified/licensed plumber would be able to provide his/her Ontario College of Trades membership number. You can also visit the Ontario College of Trades​ website to verify trade qualification status.​

How do I obtain a building permit?

​A building permit can be obtained through the Building Department at the Municipal Office. ​

Where can I purchase a backwater valve?

​Backwater valves are typically purchased through the plumber hired to complete the installation.  ​

What types of backwater valves are allowed to be installed?

​The backwater valve to be installed must be a brand approved by the Ontario Building Code​.

Can I include the costs of my restoration?

Eligible costs our outlined in the Town’s Sanitary Sewer Backwater Valve Subsidy Policy​.

Does a backwater valve require maintenance?

​Yes. You should refer to the manufacturer's recommended maintenance program for more information.​

Does a backwater valve guarantee that a backup will not occur?

No. Unfortunately, while they can offer a lot of protection, there is no guarantee that a backup will not occur because of a number of factors:

  • Installation - The device needs to be installed correctly, including the location, orientation and position. If the plumber is not diligent in ensuring that the manufacturer's specifications are followed, the device may not operate correctly. It is therefore worthwhile taking the time to understand the requirements of the device being installed and verify the contractor's workmanship. Some issues are as follows:
    • Location - The device must be located downstream of all sanitary fixtures yet upstream of any connection from the foundation drain (discussed further below).
    • Orientation - Each device has directionality to it, in that it will only work if oriented correctly. Devices therefore usually have clearly illustrated arrows on them.
    • Position - The device likely has a required slope to it that must be ensured for proper function.
    • Slope - The devices typically have minimum slope requirements.
  • Your foundation drainage complicates things - If your home's foundation drainage is collected by a sump and then discharged to the lawn, a backwater sanitary valve has a good chance of being suitable. If your foundation drain is connected to the sanitary sewer, the best scenario is to sever that connection. A connected foundation drain is problematic for two reasons:
    • If the connection is downstream of the backwater sanitary valve, during a backup sewage will not backup into your home but will backup into the drainage materials around your foundation, including the weeping tile.
    • If the connection is upstream of the backwater sanitary valve, then in all likelihood, when the valve closes during a rainfall event the drainage of groundwater around your home may backup into your basement, since it cannot get away.
  • Maintenance - Backwater sanitary valves are not maintenance-free items. They are mechanical devices in a dirty environment requiring regular maintenance and cleaning to best ensure they will operate properly during a backflow event. Manufacturer's recommendations for the type and frequency of maintenance should be followed.
  • Knowledge - Take a moment now to consider a closed backwater sanitary valve. During an event where the gate is closed, backwater cannot get into your home. This is great and what you want, but unfortunately, during this this event, the opposite effect is also true - sewage from your home cannot get out. Your home's internal plumbing has limited storage capacity. If the gate is closed, and you happen to take a shower and run the laundry at the same time, this may rapidly fill up the space in your plumbing and if is too much for your plumbing to hold, it will start coming out in your own home, at the lowest available fixture - usually a floor drain or basement shower stall. Knowledge is key. Heavy rain or an intense snowmelt is not a good time to use a lot of water within your home.

How can I protect my home from basement flooding?

​Along with damaging property, basement flooding can cause long-term health impacts to you and your family. The following provides info on key areas that may require attention in order to reduce the risk of basement flooding to your home. The Institute for Catastrophic Loss Reduction has created a booklet​ to outline steps that you can take to protect your home. 

How do I apply for the subsidy?

​Homeowners interested in participating in the subsidy program are encouraged to first review the Town's Sanitary Sewer Backwater Valve Subsidy Policy.  

The application for the subsidy can be found here:

SSBWV Subsidy Application

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