Treated Effluent Goes Back Into Water Supply

"Water experts say community perceptions remain a sticking point and the public will need to be persuaded that drinking purified wastewater is a safe, viable option." Photo: Rodger Cummins

The state government will again consider introducing treated sewage into Sydney's drinking water supply as a means of meeting the city's future water needs, even though the idea was rejected by the Labor government five years ago.

Water experts say community perceptions remain a sticking point and the public will need to be persuaded that drinking purified wastewater is a safe, viable option.

But concerns about energy use associated with desalination, and environmental concerns about building additional dams, have propelled the unpalatable option into future planning.

he Coalition is reviewing the Metropolitan Water Plan to secure water supplies for Greater Sydney beyond 2025.

The chairman of an independent panel advising the review, Chris Davis, confirmed that "all options are up for grabs", including the reuse of highly treated effluent for drinking.

"[The government] needs a plan that brings in the obvious and most cost-effective options straight up, and others that are marginal in terms of costs and palatability if needed," said Mr Davis, who is also the National Water Commissioner.

"The previous government had some constraints on what it was prepared to consider, but the new government doesn't seem to have any hang-ups. [Now] it's just a question of whether it stacks up."

Population growth and climate change impacts are expected to stretch water supply in most large Australian cities over the next 20 years.

But previous attempts to introduce treated effluent into drinking water have run into staunch community opposition.

"I think people need to be convinced that it's safe and reliable," Mr Davis said.

"They need to get over the hang-up of thinking about where the water came from, and being offended by that."

The review will also examine options such as harvesting stormwater for drinking and the future role of desalination.

In 2006, Toowoomba residents voted down a plan to drink their own purified sewage, even in the face of a critical water shortage. Two years later, public pressure forced the then Queensland premier, Anna Bligh, to mothball plans to add recycled wastewater to Wivenhoe Dam. A proposed scheme in Goulburn also failed to win support.

But the notion has gained momentum in Perth, where a pilot plan is under way to replenish groundwater supplies with treated effluent.

Schemes for recycling sewage for drinking exist in several countries, including Namibia and the US, and ''unplanned'' recycled effluent already indirectly enters the drinking water systems of many cities.

The NSW Finance and Services Minister, Greg Pearce, would not speculate on the review, but said the panel "will consider all options for water supply".

By Nicole Hasham@The Sydney Morning Herald