Overflow relief gullies
An overflow relief gully (ORG) is a grated outlet located in the ground outside your home, usually near the laundry. It's designed to act as a release valve in the event of a blockage or if there's excess rainwater in the sewerage network. It forms a critical part of your household plumbing and helps prevent sewage from flooding your house by directing the overflow outside.
If a sewer blockage occurs, or the sewerage network can’t cope with rainwater during a storm, the ORG fitting should pop off to release the pressure and direct the sewage away from your home.
Important
Preventing stormwater from entering the sewerage network helps reduce sewer overflows.
- If your ORG is set too low or your property is in a low-lying area, it can flood and contribute to stormwater entering the sewer system.
- Improper stormwater connections from downpipes or water tanks being connected to ORGs or sewer pipes can also contribute to stormwater inflows.
Plumbing regulations require ORGs to be installed:
- So they sit at least 150mm lower than the lowest internal household drain. Because they are the lowest point, any sewage that can’t go down the sewers will flow out of this point rather than backing up in your household pipes and overflowing inside.
- At least 75mm above ground level to avoid collecting stormwater during heavy rain.
An ORG should only be altered or installed by a licensed plumber.
ORG cap installation FAQs
Yes, but once installed, the ORG cap will become part of the private plumbing on your property and therefore will be your responsibility to maintain.
