An improved understanding of hydrologic processes, groundwater models and underpinning data is key to understanding how much water is recharged into aquifers, a new report has found.
New water research in the Murray-Darling Basin led by Flinders University found the connection between aquifers and rivers was crucial for water management in the Murray-Darling Basin.
National Centre for Groundwater Research and Training’s director Professor Craig Simmons, who is also a professor of hydrogeology at Flinders University, said groundwater models were uncertain — and understanding, quantifying, managing, reducing and communicating this uncertainty was critical.
Groundwater provides more than 30 per cent of Australia’s total water consumption and generates national economic activity worth more than $34billion a year across agriculture, mining and industry.
‘‘Understanding critical socio-economic drivers are a vital part of integrated groundwater management in the basin. Science alone is necessary but insufficient,’’ Prof Simmons said.
‘‘This is all about better science and social science to underpin better management and policy in the Murray-Darling Basin, and the successful implementation of the Murray-Darling Basin Plan.’’
He said valuable lessons learned through the study were applicable to other key water sources.
‘‘These issues are common to many other groundwater and water management problems in Australia and internationally,’’ he said.
Groundwater represents 97 per cent of the fresh water on earth, which supplies half of the world’s drinking water and 43 per cent of the water used to irrigate crops.
However, groundwater depletion and pollution are enormous and pressing global issues according to Prof Simmons.
The new report studied four critical areas of water science and management in the Murray-Darling Basin including how recharge occurs into groundwater aquifers and how to reduce uncertainty of recharge estimates, improving understanding of poorly understood connections between surface water and groundwater, understanding the connections between rivers and aquifers, and improving ways to manage groundwater systems.
‘‘This is important because recharge is the input of water into the groundwater system and a key component of the water balance and computer modelling — a crucial component for managing groundwater,’’ Prof Simmons.
‘‘As an example, a bore located right near a river may be counted as a groundwater allocation when it is only a few metres from the river and is almost certainly pulling water from the river.’’
The report also said establishing critical social, economic and environmental triple bottom lines for integrated groundwater management was key and would involve integrated assessments that included crucial socio-economic studies.
Recent studies have also shown that groundwater depletion is occurring at a rate that exceeds replenishment and that one third of the world’s major aquifers are under serious stress.