Rainwater tanks

A rainwater tank is a great way to capture and store rainwater from your roof to use around your home and garden.

When your rainwater system is properly installed and plumbed into your home, it could save up to 40% of your drinking water supply. This could save you up to $200 a year.

It’s important to remember that rainwater tanks require regular maintenance. Below are some simple steps to check that your system is working and easy maintenance tasks to help keep your tank clean and reliable.

How to check if your system is working

Check there's rainwater in the tank

Have a look inside the tank or knock on the side and listen for sounds of any water inside. The water level may be low if there hasn’t been much rain lately.

Check your pump and mains switching device are plugged in and switched on

If your rainwater system has a pump, it may be on the inside or the outside of your tank. If your system is gravity fed, skip this step.

Check you’re using rainwater

Turn on a tap, flush a toilet or turn on your washing machine (if it's connected to your tank) and listen for sounds that your pump is starting up. Don’t have a pump? Just check that the water is flowing.


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How to maintain your tank

Your gutter, screens and downpipes are key components of your rainwater system. They divert water from your roof into your tank and are commonly overlooked when it comes to maintenance.
Simple ways to prevent blockages and improve the water quality of your system include:
  • trimming back overhanging vegetation
  • regularly checking and cleaning your gutters
  • removing leaves and debris from your roof's catchment area
  • clearing your screens and downpipes 
  • installing a good quality gutter guard and downpipe screen

When it first begins to rain, the rain will wash debris, dirt and leaf litter from your roof and gutters into your rainwater system. A first flush device diverts the first flow of dirty rainwater to a separate chamber, stopping it from entering your tank. This chamber will slowly empty the dirty water through a small restrictor that can block easily. We recommend cleaning your first flush and flow restrictor every three to six months or after each heavy rainfall event to make sure that the chamber is empty and clear of blockages.

Not all systems have a first flush device. If you are not sure what to look for, watch the video below.

How do you clean your first flush device?

  1. Unscrew the bottom of the first flush device. Take care to avoid being splashed by dirty water as it rushes out.
  2. Rinse out the bottom cap that you unscrewed (and all its components) with fresh water.
  3. Reassemble everything as you found it.

A tank inlet screen stops leaves, debris and mosquitos from entering your rainwater tank. Make sure you clean them regularly. If your screen is screwed in, you can buy removable tank screens that fit on top of your tank and are easy to clean.

Check if you need a filter on the outlet of your tank. If so, we recommend checking and maintaining your filter monthly until you are able to determine how often this needs to be done for your system. Follow the manufacturer's instruction to clear or replace the filter.

A mains switch detects the water level in your tank and if the tank is low, empty or if your pump has stopped it will switch to the mains drinking water supply.
Regularly check your mains switching device and pump to make sure they are working as they should. Sometimes they can fail after an electrical storm or blackout and will need to be reset manually.
Check your owner's manual, or manufacturer's instructions so you can identify when your system has failed.

Not all systems have a pump and mains switching device. If you're not sure what to look for, watch the video below. 

What to do if you find a problem

If you think your system may not be working properly, contact a rainwater system specialist for advice on how to correct and maintain your system.

Alternatively, contact our WaterFix team for a quote. Our specialist technicians can check that your system is working correctly and provide you with a quote to repair any problems.

To book an appointment

Call us on 1800 807 475 weekdays from 7.30am to 5.00pm or email your details and address to rainwatertanks@sydneywater.com.au

Having the below information ready to go, will help us get started.

  • What problems have you experienced with your system?
  • How often do you hear your pump running? 
  • When was your system last cleaned (if at all)?
  • What is your system connected to, eg toilets, garden taps, irrigation, washing machine?
  • When was your tank installed?  
  • What size is your tank?

    Rainwater tank

    A rainwater tank is a great way to capture and store rainwater to use around your home and garden. Remember that rainwater tanks need regular maintenance.