Did you know that a fairly simple valve can sit in between your dry, comfortable home and a major flooding disaster? Most Australians are unaware of this valve but should certainly make sure that it's in good condition, especially before the rainy season takes up residence. Where is this valve and what do you need to do in order to keep an eye on it?
Stormy Times Ahead
Australia is well-known for its wild weather, and in the course of just an "average" thunderstorm, billions of litres of water can be released and dumped upon the community that sits beneath. Most developed places have a plan to deal with this type of event and have a drainage system that is meant to accommodate the water– at least to a certain extent.
However, it's not unusual to see a certain amount of overflow in this situation, as there is only so much room on the ground and sewer pipes can only be built to a certain size, after all. As the storm rages above, so the underground system reaches capacity, and as it does so, water combined with sewage will start to move in the opposite direction to that intended. There is a danger that it can infiltrate an individual property, and this is where the aforementioned valve comes into its own.
Valve in Action
You will have a backwater valve fitted in between the interior of your property and the public sewer system. Typically, it is close to the property line, and you should familiarise yourself with its location and its condition.
How It Works
Inside the valve is a one-way flap that's normally set to allow water and sewage to exit your home and flow into the public system. It is connected to a flotation device that sits in a water chamber, and this will detect if water starts to flow the wrong way back towards your house. When this happens, the flap will close and will keep your home safe until the emergency event passes. At this time, the water level on the street side of the valve will drop, and gravity will return the flap to its normal position so that life can continue as before.
These valves are quite hardy, but they are not designed to last forever. In particular, you need to keep an eye on the o-rings and seals that help to situate the valve, and you may also need to replace the float mechanism occasionally. Try to avoid flushing anything other than liquid down your drain, especially baby "wipes" and similar materials that could damage or clog the valve.
If it's been some time since this valve was inspected, call in a valve repair contractor to take a look for you.