Following the success of a three-year trial, the corporation is awaiting Department of Environment Regulation works approval for Stage I construction of the Groundwater Replenishment Scheme.
Groundwater replenishment cleans treated wastewater to drinking water standard.
The by-product of flushing toilets, showers, washing clothes and dishes can be ‘banked’ for later use.
Ultimately, the corporation hopes to be returning 28 billion litres of recycled water annually to underground storage.
Similar schemes operate in Orange County, California, in Singapore and Windhoek, Namibia but this would be an Australian first.
A corporation spokeswoman said the first of three stages would replenish seven billion litres into groundwater supplies annually.
‘Subject to approvals, we anticipate construction will start in July 2014 and be completed in mid 2016,’ she said.
‘Stage II will increase production to 14 billion litres, scheduled for completion in 2018 and Stage III will further increase production to 28 billion litres, scheduled for completion in 2022.’
Once works approval is given and a preferred contractor selected, the application will go to Water Minister Mia Davies for final approval.
Under the WA Health Act, the corporation also needs Department of Health approval to construct wastewater infrastructure.
The Department of Environment Regulation has extended its public comment period for the works approval to February 20.