A new study has found that water-saving subsidies lead to more water extraction in the Murray-Darling Basin.

The Australian Government’s $4 billion irrigation efficiency program has allowed to irrigators who received irrigation infrastructure funding to extract up to 28 per cent more water than those who did not receive any funds, according to experts.

This increased extraction has significant impacts on the environment and other users.

The subsidies are designed to help irrigators upgrade their infrastructure technology to save water and return some savings to the environment, in a bid to increase stream flows and ultimately reinstate a sustainable level of extraction in the Murray-Darling Basin (MDB).

Water management experts from UNSW, The University of Adelaide, Australian National University (ANU) and the Environmental Defenders Office have published a new paper in the international journal Resources, Conservation and Recycling.

It analyses almost 2500 on-farm MDB irrigation surveys, with surveys in 2010-2011 and 2015-2016, identifying a “rebound effect” of increased water extractions, coinciding with the Australian Government’s investment in irrigation infrastructure upgrades.

“The ‘buyback’ of irrigation water has put water back into the rivers, but our research found the subsidised infrastructure program could be ‘robbing Peter to pay Paul’ by enabling more water extractions than water recovered through the efficiency program,” says environmental scientist Professor Richard Kingsford.

The study also found that reductions in extractions from the MDB - supposedly commensurate with increases in environmental flows - may have been overestimated, particularly in the Northern MDB.

Additionally, it found that half of all irrigators surveyed agreed that the taxpayer-funded program for the irrigation infrastructure was “wasteful and inefficient”, and that the program favours corporate agriculture, in terms of subsidy amount per entity, more than family farms.

Prof Kingsford said the findings cast uncertainty on the long-term sustainability of the basin’s rivers and the communities which rely on them for their livelihood.

“We found water consumption is not being controlled as required by the Basin plan, which means the health of rivers and groundwater systems in the MDB will continue to degrade, without even accounting for the current and future threat of climate change,” he said.

“We call upon the government to consider our findings as an opportunity to continue developing and implementing transparent, fully audited and robust accounting and accurate measurement of all forms of water extractions across the MDB for the sake of the environment and the communities which depend on the Basin.”

The researchers recommend further MDB water and rural policy actions to address these water governance challenges, including improved compliance, fines and regulation, and prioritising the cost-effectiveness of water recovered for the environment.