Sustainable regional development is a priority for Australian governments (Federal, State or Territory) and requires appropriate information at a range of scales to guide investment. CSIRO in collaboration with three State/Territory governments and local experts have completed the Northern Australia Water Resource Assessment to underpin future water planning and investment in three priority regions. A critical component of the Assessment was the evaluation of opportunities for future groundwater development, a task requiring significant investment in field investigations in what are data sparse regions.
Field investigations including drilling, hydraulic head observations, and groundwater and surface water environmental tracer sampling were used to improve aquifer mapping, characterise and quantify groundwater recharge and flow, and to constrain inputs and boundary conditions for water balance and risk assessment models. Models incorporating land suitability, flood inundation, depth of drilling and groundwater dependent assets were used to evaluate the potential scale of future development from several aquifers. In addition, shallow drilling, sediment sampling and analytical modelling were used to evaluate the risk of irrigation-induced salinity and watertable rise.
The Assessment demonstrates the fundamental need for integrating new knowledge from field investigations to constrain models that evaluate the potential scale and impact of future irrigation development in data sparse regions. In addition, it highlights the huge variability in hydrogeology across northern Australia, the approaches required to provide new information at desired scales, and the need for a holistic approach incorporating factors beyond groundwater. A key factor in the project’s success was the packaging of project outputs and outcomes in a way that was easily understood by all stakeholders.