Frequently asked questions

Wastewater and stormwater are managed using two separate systems.

Wastewater is the water that Sydney Water collects from kitchens, laundries, bathrooms and toilets.

Stormwater is rainwater that runs from roofs and over land into stormwater drains, which flows into local waterways. 

When it rains, stormwater can get into our wastewater pipes and the system can overload. This can cause wastewater to overflow into local waterways as well as on private properties, including inside homes. 

The results from our inspections will help us understand more about why there are higher flows in our wastewater system after it rains - so we can plan repairs, improve how our system operates and reduce wastewater overflows during wet weather.

The most common ways for stormwater to get into our wastewater system is through:

• damaged wastewater maintenance holes
  
  
• stormwater downpipes incorrectly connected to private wastewater pipes or drains
  
  
• cracked, damaged or poorly sealed private wastewater pipes and fittings that can allow groundwater to enter
  
  
• damaged or low-lying overflow relief gullies, which should operate like a safety valve and prevent stormwater from entering private wastewater pipes.
  
  
  

Our inspections include visual checks and smoke testing of private wastewater and stormwater pipes and connections, to make sure they are functioning correctly and connected properly.

• Visual inspections

We’ll take photos and videos as required to document our inspections. 

We will look at:

• wastewater maintenance holes – to make sure they are sealed and not damaged
  
  
• stormwater downpipes – to check they are not connected to a wastewater overflow relief gully or wastewater pipes
  
  
• drainage channels and stormwater drains – to make sure they are not collecting ground and surface water that lead to an overflow relief gully
   
• overflow relief gullies (gully traps) – to check whether they are damaged or too close to the ground, so surface and stormwater can enter the wastewater system.
  
  
  

• Smoke testing

A small amount of smoke will be pumped into your private wastewater system from the inspection opening, or our maintenance hole on each property. 

The smoke is more like a mist – it is environmentally safe and will disappear after a few minutes without any odour. 

The noise from the generator that provides power to the smoke machine sounds similar to a lawn mower and will run for short periods during the testing. 

Smoke testing is an effective and helpful way to:

• show us if our wastewater maintenance hole is damaged
  
  
• check for leaks in pipes and fixtures
  
  
• locate where cracked, broken or unsealed pipes or joints are underground
  
  
• find out if stormwater downpipes are incorrectly connected to the wastewater system.

If smoke escapes from the wastewater system, it will be visible above the ground. 

This will show us where there may be damage or incorrect connections, so we can investigate and plan repairs or improvements.

We will update property owners and residents about one week before we expect to start our inspections. Smoke testing may need to be postponed if it’s raining, cloudy or the ground is too wet.

You do not need to be at home during the inspection, but we will need your help each day during the week that our work is planned on your property.

Please:

• make sure that all pets are safely secured, gates are unlocked and we can safely access the front and back yards of your property
• put some water in all your sinks, and make sure any floor drains in the kitchen, bathroom and laundry are covered.
  
  
  

It’s normal to see smoke coming out of your private wastewater vent pipes, which are usually located on the roof or side of the house. This shows that the vent pipes are in good working order and your wastewater system is connected correctly.

You may see smoke coming from the outside drains or gutters on the property, and sometimes it might enter the home through the laundry, kitchen, or bathroom drains. This is why we ask you to put some water in your sinks and cover your floor drains during the inspection. 

The smoke does not indicate a fire, but please let our team know if you see smoke in your home during our inspections. The smoke will clear in a few minutes with normal ventilation.

We have notified NSW Fire and Rescue and NSW Police about our smoke testing work in your area. We will have signs in place to let the community know about our inspections.

No – there will be no impact to your water or wastewater services during our inspections. You can continue to use your sinks, taps, toilets, showers and other fixtures as normal.

We will leave a card in your letterbox to let you know when we have completed our inspection.

Once our inspections are complete, we will advise property owners about any improvements we identified at the property. This includes providing details of the required repairs, what steps can be taken or how Sydney Water can help.

Emergency Relief Structures are used to help prevent wastewater overflows from being released through maintenance holes or private plumbing connections. 

They are effective in protecting the wastewater system from damage, particularly during extreme wet weather - by stopping uncontrolled wastewater overflows to protect homes in low lying areas, and the wastewater system from being damaged.