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Sewerage and recycled water

Your sewage is piped to one of the city's four sewage treatment plants and treated to a high grade recycled water which can be used for non-drinking purposes.

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Illegal stormwater connections

Every time it rains our sewerage system is under threat from illegal stormwater connections flooding the sewerage network.

Stormwater is rainwater that runs off surfaces such as lawns, roads, roofs, carparks and natural ground surfaces.

Know your water types and send it down the right pipes

Stormwater and sewage do not mix! It is illegal to direct stormwater or rainwater into the sewerage system via your Overflow Relief Gully (ORG). The ORG is the drain-like feature with a grated lid that can be found in the ground outside your home.

Sewage overflows can occur when stormwater enters the sewerage system during periods of rainfall. The excessive water puts the network under immense pressure which can cause pipes to back up and force open sewerage manholes, causing an overflow or spill.

By detecting and fixing any points on your property where rainwater may enter the sewer, you will be doing your part to protect your property, neighbourhood and the environment against wet weather sewage overflows.

The following information will assist you in determining whether or not an illegal stormwater connection exists on your property.

Swimming pools connected to the sewer 

Discharging pool water to the sewer within six hours after a rain event can cause a sewage overflow. Check where possible that only backwash water enters the sewer. Most pools have a valve that can be set to divert backwash water to the sewer and overflow water to the stormwater system.

Stormwater pipes connected to the sewer (or your ORG) 

All your stormwater must flow to a rainwater tank, the road kerb or a stormwater pit. Occasionally in older homes it may be plumbed directly to the underground stormwater system where the discharge cannot be seen. This is only the case when the street is higher than your house and there is no grated stormwater pit in your backyard.

If the downpipe from your roof is located near your sewerage pipe or appears to drain into it, an illegal connection may exist.

If you think your stormwater pipes are connected to the sewerage system, please have them inspected by a licensed plumber.

Your Overflow Relief Gully (ORG)

Your ORG is an important part of the sewerage system that directs sewage overflows outside your home, rather than inside your home. It has a grated lid and can be found on the ground outside your home. It is connected to the main drain to stop sewage entering the house when an overflow occurs.

Related information

Jump to key information
  • Where can rain water or pool overflow enter the sewer?

    Rain water or pool overflow can enter the sewer via the ORG, excess pool water being discharged to the sewer instead of the stormwater system, or from pipes illegally connected to the sewer or your ORG.

  • How do I check if I have a compliant ORG?

    • Visually inspect your ORG, there should only be one of them and it should be close to the external wall of your house.
    • Ensure there is no landscaping, paving or items (i.e. pot plant) obstructing the ORG.
    • The ORG should sit 75 millimetres above ground level and 150 millimetres below the lowest plumbing fixture inside your home.
    • Have a licensed plumber raise the ORG in accordance with plumbing regulations or install an overflow relief cap.
  • How do I check if I have a compliant swimming pool connection?

    • Confirm  your backwash cycle is about five minutes.
    • Check that only backwash water enters the sewer.
    • Direct overflow/excess pool water to stormwater.
    • Only filter backwash should discharge to sewer.
    • No pool water should be discharged to the sewer within six hours after a rain event.
  • How do I check if my stormwater pipes are compliant?

    • Hose water into each of your downpipes and ground level drainage points (in isolation) and check that each one discharges to a stormwater outlet.
    • If you have a rainwater tank, overflows must go to the stormwater system.
    • All stormwater must flow to a rainwater tank, road kerb or grated stormwater pit.
    • Stormwater should never flow into the sewerage system.