What is Backflow and why does it matter?
Backflow is when water in a municipal water supply flows the wrong way. This has potentially high risks as water supply contamination can result. To ensure the safety of the water supply here in Toronto we have a Backflow Prevention Program which includes different requirements for properties based on the risk they pose. Some properties, such as large commercial & industrial facilities, may have to put in place practices such as backflow prevention devices to reduce the likelihood of problems.
What causes Backflow and how to prevent it?
So, how does it happen you ask? Backflow can happen for a number of reasons but essentially the water supply is intended to flow one-way and there are two main types of backflow that can occur. The first is “Back Pressure” which is caused by an increase in the pressure of the on-premise water supply, this could be from a large change in temperature, the elevation of a water tank, or the addition of a pump. The other type of back flow from is “Back Siphonage” which is when the main water supply reverses flow, usually as a result of a major drop in pressure of the local water supply which could happen say if a water main broke.
What types of properties need backflow measures?
To ensure the safety of our water supply here in Toronto there are various measures in place. Most stand alone residential properties do not need to put in place any backflow prevention measures, however owners of commercial, industrial, or residential properties with 5 or more units do need to be aware of their responsibilities under the water supply bylaw. Each property is assessed based on the risk they pose so, for example, hospitals, mechanics, industrial chemical factories, etc. could have dangerous backflow implications and are considered “high risk” in this case they require a “Reduced Pressure Principle Device” which uses valve mechanisms to stop backflow from occurring. In moderate risk properties a “Double Check Valve” would be required. This would have a back up valve if the first one fails, this is fine for moderate risk but not high risk properties.
Don’t get backflow and backwater confused
If you’re wondering about your own property and the requirements you’re responsible for you should talk to a registered plumbing company and get some professional advice. As an owner it is your responsibility to manage and maintain proper Backflow precautions so get informed about the requirements of the property and make sure you’re aware of any risks. The fines involved with a breach in the Water Supply Bylaw can exceed $100,000 so it’s well worth the time investment to find out where things stand today.