ORG overflow


Identifying your ORG

The ORG (overflow relief gully) is generally situated underneath an outside tap or hose fixture and may have a black plastic or metal grate over the top. It is usually surrounded by concrete. The diagram below may assist in identifying and locating your ORG:



Overflow relief gullies assist in protecting your home from blocked drains on the Council side. Waste will spill out of the ORG rather than inside your house.


The function of the ORG

The ORG is primarily designed to prevent sewage backing up inside your house. The ORG should be positioned 15cm (150mm) below your floor waste or shower waste (whichever is the lowest). It should have a removable grate on it so if there’s ever a blockage in your main pipe line or the Council main, the sewage will spill out the ORG and not inside your house because it is lower than the waste outlets in your house. If the ORG is positioned too high and the floor waste is the lowest fixture, then that is where the waste will come out so it’s important the ORG is installed properly.


The grate is attached to the disconnector trap which is generally a 100mm fitting in the ground. Its function is to maintain the water seal which stops the sewage smell from entering the house. Disconnector traps are also present under any floor waste gullies, for example in the shower or laundry. Sometimes the ORG is concealed as people don’t know what they are and cover them up. Make sure you keep your ORG clear and visible and ensure the grate can easily pop off so that you do not restrict a sewage blockage and cause it to back up inside your house. It is important not to use the ORG as a stormwater grate as this overloads the sewer system.


If the ORG is backing up, call a plumber!

If sewage is backing up out of the ORG, the sewerage pipe is most definitely blocked so it’s time to call a plumber. Stop using any fixtures such as taps and toilets if you have not already done so. If you have been using fixtures and the ORG is overflowing, it is most likely the blockage is on your side of the pipework. If you are not using any taps or fixtures adding water to the blocked system and it continues to overflow, then it is either a Council blockage or you are on a combined sewer line from cluster housing or unit developments.