Greywater re-use

What is greywater?

Greywater is re-usable wastewater from washing machines, showers, baths and basins.

The use of greywater is regulated because of the potential for it to spread disease around your home - and elsewhere. 

Infection may occur if untreated greywater is stored or used so that birds, insects, pets or children come into contact with it.

What are the benefits of greywater?

Greywater is:

  • a source of irrigation water all year round
  • a relatively easy and safe source of water to access and use
  • a good source of important nutrients for many plants.

How can you use greywater?

You can use greywater in three ways:

Manual bucketing is the cheapest way of using greywater.

It means simply collecting water in a bucket from your washing machine or shower and using it to water your garden.

You don't need permission to do this, but don't store or keep the collected greywater for more than one day. This avoids the risk of spills and bad odours.

To prevent greywater running into neighbouring properties, don't use this method when it's raining or when the soil is already saturated.
A greywater diversion device is a simple system. It diverts greywater to a small holding tank and then to an irrigation system that's below the soil surface.

These systems should be self-draining so that greywater isn't stored for more than a day.

They also have a valve to make it is easy to divert greywater directly to the sewer when it’s raining or when the soil is saturated.

NSW Health maintains a register of accredited diversion devices.

There's a range of diversion solutions available, so make sure you choose one that best meets your needs. Consider cost, ease of use, durability and ease of installation and maintenance.

Greywater treatment systems mean you can use all the greywater your home generates regardless of the weather.

After treatment, the greywater is clean enough to be stored.

Treated greywater should be almost colourless and it shouldn't have a bad odour. It is not safe to drink. 

You can use treated greywater to:

  • flush toilets
  • wash your clothes
  • water your garden using a hose, spray or drip irrigation. 
     
Greywater treatment systems are available from many suppliers. The Environmental Health team at  NSW Health accredits these suppliers.