HOUSEHOLDS across Perth will soon be drinking recycled waste water.

WA will be the first state to drink recycled water when up to 35 billion litres of treated sewage is pumped into our underground supply each year under a plan to be ticked off by the Barnett Government.

The Sunday Times can reveal the Water Corporation will recommend within weeks that treated waste from showers, washing machines and toilets be re-used to drought-proof the state.

Treated sewage has been quietly injected into Perth's aquifers during a trial that ended in December. WaterCorp will advise the Government the testing was a success with just one emergency shutdown.

However, the state Government will refuse West Australians a say in the proposal, after a public revolt stopped a similar plan in Queensland.

WaterCorp manager for water source planning Nick Turner said a large-scale project could be up and running within two years that could help drought-proof the state.

The authority's recommendation will come as part of a final report into a three-year trial in which about 2.5 billion litres of wastewater from a Craigie treatment plant was treated to Australian drinking standards and then injected into an isolated aquifer in Leederville.

Despite the trial finishing in December, the plant has continued to recharge the aquifer with treated sewage.

Under the Water Corporation plan, the same technology would be used to treat 25 per cent of wastewater from the Beenyup Wastewater Treatment plant that would then be injected into the aquifer and eventually end up in Perth homes.

Currently, water from Beenyup is discharged into the ocean.

"The results are all good, we've demonstrated that it's sustainable, that we can operate it, the regulations are in place and the public are supportive," Mr Turner said.

"We do not anticipate needing to do any more trialling.

"Our recommendation will be to proceed with expansion, but it's their call."

WaterCorp has previously said recycled water could supply 35 billion litres a year, enough for 140,000 households.

In comparison, the Kwinana desalination plant produces about 45 billion litres a year.

Mr Turner said the report was yet to receive input from the Health Department and Department of Environment and Conservation, but it was expected to be ready to go to the Government within weeks.

He said there could be no 100 per cent guarantee, but he said the plant was designed to shut off immediately if water purity was compromised.

A statement released by the corporation on March 30 last year revealed water that did not meet drinking standards was recharged into the aquifer during a "minor hiccup".

The statement said 300kL of water with a pH value of between 8.5 and 9 was allowed through, despite a guideline for the trial of 8.5.

Citizens Against Drinking Sewage spokeswoman Rosemary Morley, who successfully lobbied against a plan to introduce treated water into dams in the Queensland town of Toowoomba in 2006, said there were no guarantees.

But Ms Morley said the WA plan was different to one voted down in Queensland by a referendum.

kara.vickery@news.com.au