Sydney Water's test, and what blocks Sydney drains
Probably Sydney Water's
The overflow is past your boundary, such as from a maintenance hole on public land. Or your neighbours have the same problem, there's widespread flooding nearby, or sewage keeps coming out while nobody is using water.
Probably yours
The neighbours are fine, your drainage isn't shared with another property, there's no local flooding, and it only overflows when you run water.
Wet wipes
Sydney Water says non-flushable wet wipes contribute to 75% of wastewater blockages. Paper towel, tissues, cotton buds and hair don't break down either. Only pee, poo and toilet paper belong in the toilet.
Trees within 6 metres
Roots get into small cracks and keep growing. Sydney Water advises against planting trees within 6 metres of wastewater pipes and names jacarandas, figs, liquidambars, brush box, camphor laurel and lilly pillies among those to avoid.
If the blockage turns out to be Sydney Water's
Ask the plumber to stop and report it to Sydney Water as soon as they find the blockage is in its pipes. As long as they report it, you can claim reasonable out-of-pocket expenses, capped at 2 hours of work. A plumber who clears Sydney Water's line without reporting it leaves you with nothing to claim.
Sydney Water owns the junction where your line meets its sewer. Everything up to that point is yours, including the point of connection, and Sydney Water says roots growing into the junction there are the owner's to clear. Your line may carry on past your boundary, so a blockage under the footpath can still be yours.
Drains that only play up in heavy rain
Sydney Water says stormwater getting into its wastewater pipes in wet weather can overload them and push sewage back onto private property, even inside homes. The usual ways in are downpipes wrongly connected to wastewater pipes, cracked or poorly sealed private pipes letting groundwater in, and damaged or low-lying overflow relief gullies.
That gully, the grated drain usually near an outside tap, is meant to act like a safety valve. Keep its grate clear and don't let soil or paving build up to its rim: Sydney Water's inspectors check for gullies sitting too close to the ground, and for downpipes connected to them. An overflow from the gully is also one of Sydney Water's signs of a blockage.
Your part and the drain specialist's
You can
- Stop running water into the blocked line.
- Ask next door whether their drains are slow too.
- Look at the gully near your outside tap: an overflow there points to the main line.
- Buy your sewer service diagram from Sydney Water Tap in, so the plumber knows where your private pipes run.
Leave to a licensed plumber
- Clearing the blockage and finding what caused it
- A camera inspection when roots or a broken pipe are suspected
- Reporting it to Sydney Water if it's in Sydney Water's pipes
- Any drain repair, which in NSW needs a Notice of Work, a Sewer Service Diagram and a Certificate of Compliance
Questions for a Sydney drain specialist
- If you find the blockage is in Sydney Water's pipes, will you stop and report it?
- Can I see the camera footage and where the problem sits on my diagram?
- Are roots in my pipe or at the junction, and how do we keep them out?
- Does your NSW contractor licence cover drainage?
What we would do
Run Sydney Water's test before you ring anyone. If it points to Sydney Water, report it to them first. If it points to you, book a drain specialist, and say up front that you expect any blockage found on Sydney Water's side to be reported, not cleared on your bill. When roots are the cause, ask for the camera footage, because a clear today with roots still in a cracked pipe means another call later.