A leading environmental expert explains why Barnaby Joyce's ambitious dam building plans could be significantly constrained by economic and environmental circumstances.

The Federal Minister for Agriculture has acknowledged that funding issues still cast a shadow of uncertainty over the government’s ambitious dam building plans outlined in the Agricultural Green Paper.

Responding to concerns from listeners about the government’s dam building plans on ABC Rural Radio, Barnaby Joyce pointed out that the shortlist of dams previously compiled was only for potential sites, as opposed to confirmed projects.

Barbaby dam“We had a compendium of a 100 possible dam sites – we never said we were going to build 100 dams,” said Joyce.

While minister is adamant that he would like to “build as many [dams] as I possibly can,” he acknowledged that funding issues had the potential to stall or constrain proposed projects.

“We’ve got range of dams before..and we’ve got to work out how much the Commonwealth needs to put towards it, how much private enterprise needs to put towards it, and how much the states are going to put towards it,” said Joyce.

According to Joyce the number of dam projects cannot be confirmed until he has greater certainty concerning the exact amount of funding made available.

“When at some point in time the Prime Minister of the country says ‘well Barny we’ll put some money on the table,’ then I can work out how much we can start to put in on direction or the other direction.”

Even when funding uncertainties are resolved, however, one expert points out that, Australia is subject to a number of economic and geographical constraints that could significantly contain or impede the government’s dam ambitions.

Dr. Joshua Larsen, a lecturer at the University of Queensland’s School of Geography Planning and Environmental Management, points out that Australia’s unique circumstances will make any efforts to dramatically increase dam infrastructure a challenge.

Dr. Joshua Larsen courtesy of the University of Queensland

Dr. Joshua Larsen courtesy of the University of Queensland

Larsen points out that Australia’s unusual geography makes it a highly difficult place for the effective siting dams, and that much of the prime real estate for such projects was taken during the last big dam building binge in the second half of the 20th century.

“Prime land [for dams] requires a combination of suitable inflows (generally a reliable water supply) and suitable topography to store the water – steeper means less surface area for the same volume and potentially lower construction costs,” said Larsen to Sourceable.

“Australia, like the rest of the world, built a lot of dams between the 50s and the end of the 80’s. Australia also has the lowest area averaged surface water runoff for any continent in the world, and is also the flattest. Therefore, we have built most of the dams we could in all the suitable locations we could, and close enough to the people or industries that would actually use the water.”

Because most of the best land for dam projects is already occupied, the opportunities for further expansion remain limited.

“Any new dam projects are therefore likely to be upgrades to existing structures, quite small in storage volume, or pushing into more marginal terrain,” said Larsen.

Larsen further points out that surge in construction costs in Australia in tandem with tepid prices for the types of commodities whose production is boosted by the building of dam infrastructure makes the projects less economically appealing undertakings.

“Total construction costs (including labour) were obviously much lower when the majority of our existing dam infrastructure was built,” he said. “In contrast to construction costs, commodity prices relevant to these irrigation projects have fluctuated about a stable or declining trend, meaning we’ll have to pay much more but make the same or even less money from these projects.”

The changing economics of dam building in Australia and the fact that they will exclusively designed for irrigation purposes, as opposed to the production of hydropower, means that a highly unlikely confluence of favourable circumstances would be needed to make such projects economically viable.

“The very high cost of new projects will need to be offset by much cheaper water prices, much higher commodity yields, or higher commodity prices,” said Larsen. “None of these are of course likely to happen, so the economics become very difficult.”

Larsen believes that greater prudence and foresight must be exercised with respect to the planning of dam projects given these difficult economics, as well as the inextricable relationship between dam infrastructure and the agricultural sector in Australia and related environmental constraints.

“The argument for or against new dams in Australia can’t be separated from the debate surrounding the future of agriculture in Australia – what do we want this to look like and what direction do we want to go?,” said Larsen.

“Then we can ask if we have the water to achieve this,. But we can’t rely on a ‘build it and they will come’ approach.”