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Overflow Relief Gully

Overflow Relief Gully

Important information about your Overflow Relief Gully

Diagram thanks to the Queensland Building and Construction CommissionWhat is an Overflow Relief Gully and why should it be clear?

An overflow relief gully (ORG) is a grated drain that acts as a relief valve in the case of a sewer blockage. In other words, it allows sewage to overflow outside. An ORG is required for all modern properties in Australia and is typically located outdoors near the kitchen or laundry. This system prevents sewage from emptying into your home during any blockages (or if the local sewage system is inundated with flood water during any flooding incident). 

For this reason, it is important to check the ORG outside your home regularly.

Preventative maintenance measures

Here are some simple preventative measures to help ensure your property’s ORG is functioning correctly.

  1. Most importantly, make sure the grate at the top of the ORG can easily pop off to guarantee overflow can escape.
  2. Check that the ORG is not covered by any objects, such as landscaping items or garden beds, because a blocked relief gully may result in sewage being pushed back inside your property.
  3. Confirm that stormwater drains do not empty into the ORG as this can cause the system to overflow or become blocked from debris.
  4. Get a plumber to check that the ORG is at least 150 mm lower than the lowest waste outlet in your home and also 75 mm above surrounding ground to prevent stormwater from getting inside.

What does an ORG look like?

An ORG is a drain-like fitting made of plastic or metal alloy located outside your house; usually close to your bathroom or laundry external wall. The grate at the top of the ORG must be able to pop off easily and not be cemented in. ORGs can look different on various properties and should not be confused with stormwater drains.

ORG information video

Watch this great video from our friends at Urban Utilities that has some more information about ORG's.