What sources to consider

Here you will find information about alternative water sources that may be available for your land development.

Options at lot scale

A number of non-drinking water solutions can be implemented at lot scale. Generally no involvement is required from Water Corporation for non-drinking water solutions that are operated by the householder or land owner.

Best use of rainwater tanks

In Perth, we recommend water from rainwater tanks is best directed to non-drinking uses such as:

  • irrigation of lawns and gardens
  • external taps for gardens and car washing
  • toilet flushing
  • cold water laundry connections.

People connected to the public water supply system should use this water for drinking water. This is in line with the Australian Drinking Water Guidelines (2004) which state that above-ground rainwater tanks generally provide a safe supply of water. The guidelines recommend however, that for household drinking water supply, emphasis should be on selecting the best quality source water available.

Why rainwater tank water should be used inside and outside

Perth’s weather patterns of wet winters and dry summers result in rainwater tanks being full or close to full for much of the winter and empty or close to empty for most of the summer.

Using rainwater inside the home, as well as for outdoor uses ensures the tank is emptied on a regular basis, allowing it to fill up more times during the year (as opposed to just summer for garden watering).

Rainwater tanks aren't suitable for homes in much of the north of the state as houses don't have gutters due to heavy seasonal rainfall patterns.

How can greywater be recycled?

Everyone can recycle greywater easily by capturing this water with buckets and using on lawns and gardens. To recycle more, a greywater treatment system needs to be installed.

What approvals are required?

You need to get approval from the local council to install a greywater system that produces less than 5000L/day of greywater. Systems larger than this and using greywater inside the home can be approved by the Department of Health.

Connection into the system or modifications to internal plumbing need to be carried out by a licensed plumber.  
Your local council or the Health Department will grant approval once they have inspected the greywater system to ensure it has been installed properly. 

The use of garden bores is managed by the Department of Water. Garden bores draw water from shallow groundwater, and can provide an alternative water supply in areas where there is shallow groundwater of good quality.

Where are bores suitable?

The opportunity for garden bores is highly variable across Perth as groundwater levels are declining in some areas. The Perth Groundwater Atlas identifies area where bores are suitable. 

Options at development scale

Groundwater

Groundwater may be an appropriate source for non-drinking water uses such as the irrigation of public open space. Groundwater allocations are managed by the Department of Water.

Recycled water

Generally, recycled water can come from two main sources:

  • treated wastewater from a wastewater treatment plant (WWTP)
  • sewer mining, or taking the wastewater before it reaches a WWTP.

We operate over 100 WWTPs and about 80 water recycling schemes across Western Australia. In some locations, WWTPs are owned and operated by local government. 

In Western Australia, many water recycling schemes irrigate local parks and ovals. Other uses include: 

  • industrial processing
  • irrigation of non-food crops (such as trees, woodlots, turf)
  • construction/dust suppression.

Recycled water could also be used to irrigate some food crops and to provide an environmental benefit, such as the recharge of an aquifer. 

For uses that provide community benefit, there is no charge for the recycled water supplied by Water Corporation. Local government and other operators may be required to pay for any additional treatment and piping costs. 

The total cost of recycled water will depend on number of factors, such as proximity of wastewater infrastructure and water quality requirements.  They are determined on a case by case basis.

Sewer mining is the process of extracting, treating and using wastewater before it reaches a WWTP, and usually involves:

  • extracting raw wastewater from the sewer main upstream of a wastewater treatment plant
  • delivering the extracted raw wastewater to a decentralised treatment facility
  • treating it to ‘fit for purpose’ quality
  • delivering recycled water to the end user
  • managing residuals.

Stormwater

Some local government’s collect stormwater from drains and use it locally for irrigation purposes. Stormwater can also be captured and used on site.