As part of the Government�s Water Forever plans, treated wastewater will be further processed to drinking standards and then recharged into an aquifer for later use as a drinking water source.
Water Minister Mia Davies toured the site on Tuesday.
She said the $124 million plant would be able to recharge up to 14 billion litres of water each year and could be expanded to 28 billion litres when needed.
She praised Perth residents for their support of the scheme, which Water Corporation consultation had revealed public support at 73 per cent.
When construction is completed, people will be able to tour the water recycling plant.