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Plumbing services 24 hours a day, 7 days a week.


What is backflow?

In plumbing terms backflow is the unwanted reverse flow of water within a water pipe, in a worse case this could be contaminated water mixing with fresh drinking water, causing people to get sick or much worse.

A specialist backflow prevention expert can determine the nature of the hazard that may exist and provide a solution to minimise this risk.

A hose left in a bucket or a tank can allow the content of that bucket or tank to enter your drinkable water give the right circumstances, and you’ll never even know it’s happened until after you are affected by the result. Think of all the nasty thing that could be in a bucket or tank.

What is an Overflow Relief Gully?



 Straight from Yarra Valley Water

What is an Overflow Relief Gully?

An Overflow Relief Gully (ORG) is a drain-like fitting located outside the home, that allows sewage to overflow away from the interior of your home and outside to the garden if there is a sewer blockage.

How does it work?

If a sewer blockage occurs, the ORG fitting should pop off to release the pressure and direct sewage away from your home. It is the home owner’s responsibility to make sure their home is fitted with a properly designed and operational ORG. When an ORG is not functioning correctly the property damage and health risks associated with sewage spilling inside or under a property are greatly increased. 

Claiming insurance following a sewer spill inside a property

As it is the home owner’s responsibility to make sure their home is fitted with a properly designed and operational ORG, an insurance claim for damages resulting from a sewer spill inside a building may be reduced when a non-compliant ORG is believed to have contributed to the magnitude of the damage.

Make sure your Overflow Relief Gully is not:

  • underneath the property as a result of not being moved when a house extension was built (a plumber should move the existing ORG as part of constructing a house extension)
  • blocked with concrete as a result of driveway or paving construction
  • covered by landscaping or garden beds
  • covered by any objects
  • unable to pop off because it is corroded, filled with silt or concreted in
  • a model which requires manual twisting in order to pop out.

Make sure your Overflow Relief Gully has:

  • a clear drainage path (so spills drain away quickly without causing damage)
  • a fitting that can pop off completely
  • been installed at the correct level*
*at least 150mm lower than the lowest fitting in the house (e.g. basin, shower, toilet, etc.) and usually 75mm above the surrounding ground.

What does it look like?

The shape and size can vary greatly. Generally they are between 100mm and 150mm in diameter and are either made of plastic or metal alloy. In some properties there are fittings that may look like an ORG that are called ‘disconnector gullies or gully traps’. These can easily be converted to an ORG, provided it is lower than any other waste outlets in the home.

Do all homes have an Overflow Relief Gully?

Most properties constructed after 1976 have an ORG, surrounded in concrete, near an external wall (or in special cases they may have a reflux valve). Buildings connected to the sewer prior to this date do not have an ORG unless additional work has been carried out since 1976. We strongly recommend that all homes have an ORG installed. When it is not possible to install a complying ORG, a reflux valve may be installed.

What is the difference between ORG models?

As ORGs have been installed since the late 1970s, many different models exist. We strongly recommend you install an approved model that is unhindered and pops off completely in an emergency. 

Are ORG’s covered by regulations?

There are plumbing regulations that apply to the installation of ORG’s (National Plumbing Code AS 3500 1998). If you already have one installed, a licensed plumber should make an assessment as it may need to be repaired or replaced. If you don’t have one, contact a licensed plumber for a quote.

The difference between a Bidet and a Bidett

This is a traditional Bidet, notice the water shoots up from the bottom. The installation of this fixture requires the application of many plumbing rules and is very expensive to comply with all those rules and regulations, to do with backflow prevention, water temperature, all very boring things unless your a plumber.

A Bidett is a poor man’s Bidet, the water comes over the top. They are not subject to the same rules and regulations and are much cheaper to install.

or a kids hand basin

I think this one was installed incorrectly

Roof Safety

If you fall off a single storey roof you will most likely be seriously injured or dead. If you fall off a double storey roof you will definitely seriously or more likely dead. Evaporative cooling on roofs will need to be services, and they will break down. When this happens somebody will need to access the unit to repair it. You cannot get up on a roof if it is wet or too hot. This can be time consuming, require multiple service technicians, anchor points, ropes and harnesses and as a result the cost can be seemingly expensive.

Air Conditioners over 10 years old

Appliances over 10 years old break down. Generally they have specific parts and electronic control system. If a circuit board is faulty these can be expensive to replace, these can sometimes be repaired be sent to a specialist repair that may or may not be able to repair the electronic circuit board. Repairs can take, a week or several weeks and this can be very difficult emotionally, to cope without. The electronics and design is over 10 years old. There is no guarantee that another problem will not occur.

Do you pay for an expensive repair on an appliance that is older than the life it was designed for?

Do you install a new system, more efficient, updated technology with a new warranty generally 3-5 years?

Your repairer cannot make the decision for you, they cannot be held responsible for the decision you made, especially if the repair cost more than a new system would to install.

Woolley's Plumbing is now part of the Gallant Group. Learn More