A framework for future groundwater use

The southeast of South Australia is a region where groundwater resources are highly allocated, in increasing demand, and potentially impacted by reduced rainfall and groundwater recharge due to climate change. The conventional gas industry operating in the region relies on groundwater resources for the drilling and construction of wells and, while it is not a major consumer of groundwater, the increasing demands on future available water resources has implications on water security for communities, the environment and multiple industries, including agriculture, forestry and onshore gas. 

Given these increasing water resource requirements, there is a need for a sustainable and holistic approach to managing this highly sought after resource. A CSIRO GISERA study set out to improve management of groundwater in the region through the development of a decision support framework. Researchers consulted with stakeholders and developed various groundwater scenarios to investigate changes in groundwater availability and use. These stakeholders included landholders, forestry operators, irrigated agricultural businesses, onshore gas developers, environmental groups, and local and state government. 

To develop this research-based framework, predictions of groundwater recharge and drawdown were modelled for the period 2020 to 2100 utilising six-month summer and winter stress periods. The researchers used probable climate scenarios, and patterns of future water use for agriculture, forestry, onshore gas and other industries. 

The main outcomes of the project showed future climate scenarios indicating a drying climate for the region. Groundwater modelling predicted a significant reduction in net recharge and decreases in water levels for all future scenarios due to climate change. In addition to the more widespread drawdown caused by climate change, increased extraction rates would result in localised drawdown.  These projected decreases in groundwater levels are likely to affect wetland and other high-value groundwater dependent ecosystems, as well as impact existing groundwater users. 

While stakeholders from the different sectors have distinct perspectives on management actions, the value placed on water and sustainable water management under a changing climate is a shared sentiment. The resulting decision support framework will be able to assist policy development and decision makers to manage the valuable groundwater resources in the region.  

For further information about this research, visit the research page for the project on our GISERA website.