Great Artesian Basin
The Great Artesian Basin (GAB) is one of Australia's most significant hydrogeological entities. Covering more than 1.7 million square kilometres, the GAB underlies parts of Queensland, New South Wales, South Australia and the Northern Territory. The GAB contains a vast volume of underground water (estimated at 64,900 million megalitres) and is the largest groundwater basin in Australia. Groundwater from the Great Artesian Basin (GAB) is a vital resource for pastoral, agricultural and extractive industries as well as for town water supplies, supporting at least $12.8 billion in economic activity annually (Frontier Economics 2016). It is an essential resource that supports Indigenous cultural values and sustains a range of groundwater dependent ecosystems (GDEs).
Assessing the Status of Groundwater in the Great Artesian Basin
Increased and competing demands for water to support new or expanding industries, communities and the environment, as well as the complex nature of the GAB groundwater systems, are key challenges in effective long-term management of the basin’s groundwater resources. Although significant research has been undertaken to better understand the GAB groundwater system, there remain hydrogeological knowledge gaps that impair our ability to optimise the management of groundwater resources in the Basin.
The Australian Government, through the National Water Infrastructure Fund – Expansion, commissioned Geoscience Australia to undertake the project ‘Assessing the Status of Groundwater in the Great Artesian Basin’. The project commenced in July 2019 and will finish in June 2022. It will develop and evaluate new tools and techniques to assess the status of GAB groundwater resources to support responsible management of Basin water resources.
- Develop an evidence-based, low-cost, decision-making tool for government, water users and the general public to:
- monitor groundwater storage changes over time;
- identify changes in groundwater levels in a timely manner;
- identify “hotspots” - areas of high priority and increased demand that required detailed investigation in the future.
- Tested techniques, tools and information for improving the hydrogeological framework for the GAB for assessing the water balance.
- Identification of data and knowledge gaps and priorities for future research.
The work program objectives will adopt a phased approach.
- Phase 1 will involve development of project framework including establishment of Project Plan, aims and objectives, governance arrangements and Collaborative Agreements.
- Phase 2 will develop and evaluate new tools to assess the status of GAB groundwater resources, in two pilot study areas: one in the geologically complex, data-rich northern Surat Basin, the other in a relatively less geologically complex western Eromanga Basin (Figure 1). The pilot studies will develop and assess the application of new tools using Gravity Recovery and Climate Experiment (GRACE) and Interferometric Synthetic Aperture Radar (InSAR) satellite-based measurements to infer groundwater storage variations in the GAB.
- Phase 3 will involve producing a summary and evaluation of all available data and information suitable for assessing the status of groundwater resources across the GAB. This will include estimates of total water storage change and groundwater storage changes for the period of the GRACE mission (2002-2016) produced for whole-of-GAB.
- A stakeholder engagement workshop to communicate project results and outcomes.
- A synthesis report documenting the key findings and recommendations from the pilot & whole-of-GAB studies.
- Technical reports outlining all project components.
- Project summaries of each project component.
- Project datasets, tools and GIS products.
Geoscience Australia will undertake this assessment in partnership with:
- Commonwealth Department of Agriculture;
- Queensland Department of Natural Resources, Mines and Energy (QLD DNRME);
- Queensland Office of Groundwater Impact Assessment (OGIA);
- South Australian Department for Environment and Water (SA DEW);
- NSW Department of Planning, Industry and Environment (NSW DPIE);
- NT Department of Environment and Natural Resources;
- Bureau of Meteorology (BOM); and
- Various academic institutions.
Frontier Economics. 2016, Economic output of groundwater dependent sectors in the Great Artesian Basin – A report commissioned by the Australian Government and Great Artesian Basin Jurisdictions based on advice from the Great Artesian Basin Coordinating committee.
Hydrogeological Atlas of the GAB
The atlas presents a compilation of maps documenting some of the key regional geological, hydrogeological and hydrochemical aspects of the GAB. It provides insights into the current understanding of the regional geometry and physical characteristics of the rocks and water contained within this vast groundwater basin and baseline information against which future changes can be assessed.
The atlas draws upon recent work undertaken by Geoscience Australia that has contributed to a number of projects, such as the CSIRO-led Great Artesian Basin Water Resource Assessment (GABWRA) project and Geoscience Australia's Carbon Capture and Storage project. Since these projects, new information has led to some of the concepts and interpretations being revised or refined for this atlas. Two key pieces of new work that are presented in this atlas are the up to date interpretations of the extent and thickness of the major aquifers and aquitards and the basin-wide perspective of the variation of water chemistry found within the major aquifers.
The atlas and associated datasets have already proven to be a valuable information resource base for state and Commonwealth, resource and environmental agencies, water managers and communities. The Atlas will help inform water management decisions within the GAB, assisting agencies to better understand the groundwater resources and to evaluate the effectiveness of management activities.
Download a high resolution copy of the Atlas
Related article: Navigating Australia's largest groundwater resource
GAB Research Priorities Workshop
Geoscience Australia organised a two-day Great Artesian Basin Research Priorities Workshop in Canberra on 27 and 28 of April 2016.
This workshop was aimed at identifying and documenting key science issues and strategies to fill hydrogeological knowledge gaps that will assist federal and state/territory governments in addressing groundwater management issues within the GAB.
Download the summary of the Great Artesian Basin Research Priorities Workshop
GAB Water Resource Assessment
Funded by the then Australian Government Department of Sustainability, Environment, Water, Populations and Communities and the National Water Commission, the Great Artesian Basin Water Resource Assessment (the Assessment) carried out a basin-scale investigation of water resources across the GAB, assessing the status of water resources, identifying the potential impacts of climate change and resource development on those water resources and filling knowledge gaps in our understanding of the resource. The Assessment provides an updated interpretation of the geology and hydrogeology of the GAB resulting in an update of the conceptualisation of how the groundwater system operates.