19 May 2008
By Carolyn Tucker

Dams versus desalination: which is the better alternative to secure water supplies for the parched south-east?

Debate has raged since the government unveiled its controversial plan to build the $1.7 billion Traveston Dam and has been reignited with the admission that water prices are set to soar due to a blow-out in infrastructure costs.

The government’s $9 billion water grid is expected to force average household water bills on the Sunshine Coast up by almost $200 by 2012-13.

Other households in the south-east will be slugged even more as taxpayers pick up the tab for hundreds of kilometres in interconnecting pipelines, two new dams, a desalination plant at Tugun and a new recycling scheme.

The government claims its plan will drought-proof the region and give residents water security but not everyone is convinced.

Both the coalition and the government acknowledge that dams alone will not provide enough water to meet future demand.

The water commission’s long-term strategy states that climate change may have a “dramatic impact” on dam supplies and it aims to ensure desalination and purified recycled water cater for up to 30% of the region’s water needs by 2056.

The commission has already identified six sites – including two on the Sunshine Coast and one at Bribie Island – for investigation for future desalination plants.

It also supports an increase in the use of water from rainwater tanks and “giving careful consideration to other local supply sources such as rainwater harvesting and recycling”.

The coalition’s recently released water policy advocates taking some of these steps sooner rather than later.

It would build a $1.19 billion desalination plant at Bribie Island powered by renewable energy immediately, limit the use of recycled water to industrial and agricultural purposes and provide incentives for households, businesses and developers to embrace stormwater harvesting and new technologies.

Most notably, it would dump the Traveston Dam.

In an interesting exchange of traditional territory, the coalition claims its policies are more environmentally friendly while the government argues that the dam is necessary, at least in part on economic grounds.

Minister for infrastructure and deputy premier Paul Lucas said the coalition’s proposals would provide less water and cost taxpayers dearly because desalination was a far more expensive, energy-intensive option.

Mr Lucas also claimed the coalition was proposing to rob the Mary Valley economy of a much-needed shot in the arm by denying it the benefits of the dam.

“There has been substantial decline in the dairy industry in the Mary Valley prior to Traveston being announced and to pull out the potential of several billion dollars worth of construction expenditure would be a great negative for that industry,” he said. “I think there is a quiet change in the community – business and residents are seeing that the dam will mean an enormous injection into the economy.”

If he is correct, it has been missed by Kevin Ingersole of the Save the Mary River Coordinating Group who remains vociferously opposed to the dam and said to suggest the valley would not survive without it was rubbish.

“The best soils in Queensland are found in this valley – you can grow anything here – it was a huge producer of small crops before the dairy industry took off,” he said.

“Everybody knows that a dam is a big concrete wall and I suppose if you were in the concreting business you would benefit but a desalination plant would employ a lot of people too – it would just be different jobs in a different area.”

Mr Lucas’s claims about the economic benefits did not wash with the Sunshine Coast Environment Council either.

General manager Ian Christesen said the statements had a distinctly desperate ring about them.

“I think it is horrendous that he has intimated that rural production was not viable in the Mary Valley and the economy won’t survive without the dam,” he said.

Dam opponents are also sceptical about the broader argument that it is a much cheaper option than desalination.

They say the government has ignored the social and environmental cost and its figures failed to factor in the cost of lost production and the expense of transporting water supplies hundreds of kilometres from the source.

Independent experts also rejected suggestions that the cost of desalination made it a much less attractive alternative, pointing to the Perth plant as an example.

The wind-powered plant in Perth was built for $387 million and has been operating since 2006.

Last year the WA government announced plans for a second $1 billion plant which is expected to come on line around 2011 and produce water for about $1.90 per kilolitre.

The two desalination plants will push up household water prices in Perth by $30 a year from 2008/09.