Pressure Sewer Systems

Here you will find information about your pressure sewer system, how to maintain the system, and what to do if the alarm sounds.

Pressure Sewer System Unit Lid photo

What is a Pressure Sewer System?

Pressure sewer systems are small on-property units that collect, grind and pump household sewage into a pressurised reticulation system in the street which then conveys the household sewage on to a treatment plant. 

Pressure sewerage systems are not common across the city but generally in areas where a conventional gravity system is not a viable servicing option. 

Your pressure sewer unit is automatic and does not need you to do anything to operate it. Just use your shower, toilet, washing machine and any other fittings connected to your house drains normally. 

Who maintains the pressure sewer system?

The system and all relating components are owned and maintained by Shoalhaven Water and at no times are they to be adjusted, serviced, or relocated by any persons other than Shoalhaven Water operations staff.

Using your Pressure Sewer System

Ensure your system runs smoothly

The system operates like a normal sewerage system taking waste liquids from your toilet, sink, shower, bath, dishwasher and washing machine and transferring it to the reticulation system or treatment plant. To avoid blockages and damage to the pressure sewer system, the following items should not be placed in the system:

PSS items to avoid


What happens if I get an onsite blockage?

If the wastewater within your house becomes slow to drain, you may have a sewer blockage. In this instance you should call us and we will investigate whether the blockage is within the pressure sewer unit, or if it is within your internal plumbing. 

After our investigation, if the problem turns out to be within your internal plumbing, we will advise you to call a plumber. 

What to do if the alarm sounds

After heavy rain periods or power outages, the alarm function may be activated. If this has occurred, here’s what to do:

Heavy Rain - If the alarm has been activated due to a heavy rain incident, your system may have received an influx of stormwater and is working on processing the extra water. Try turning the alarm off by pressing the mute button underneath the alarm panel. Monitor the alarms flashing light, if it is still active after an hour, then call us. 

Power Outage - If the alarm has been activated due to a power outage, the unit may clear itself and the alarm will switch itself off within an hour of the power coming back on. You will know if it has happened because the alarm light will go out.

In either instance, if the alarm light is still active after an hour, then call us. Do not attempt to repair the unit yourself. The system has a 24-hour emergency storage capacity so any repairs will be carried out within the 24-hour period. At this time, you should try to minimise the amount of wastewater going into the system. 

Maintaining your Pressure Sewer System

Ensure that your pressure sewer system has been installed so that the lid is slightly above ground level. There is no need for you to remove the lid to access the pump unit or collection well, however access must be ensured to allow our team to undertake maintenance or repairs. 

  • Do not walk or put heavy weights on the plastic lid, this may cause damage. 
  • Do not touch the valves in the boundary kit.
  • Do not turn off the power to the pump unless in response to a broken discharge pipe.
  • Do not touch the vent on the pumping unit.
  • Do not cover the pumping unit.

If you go on holidays, even if it is only for a few days, you will need to flush the system before you go away. This is to avoid the possibility of the system becoming smelly in your absence. You can flush the system by running water in the sink for about 10 minutes. 

Home modifications - Contact us if you are making modifications to your home which may affect the system, eg. if you are installing a spa or swimming pool or extending the house over of near the unit or discharge pipe.