A multidisciplinary approach to the hydrological conceptualisation of springs in the Surat Basin of the Great Artesian Basin (Australia)

The impact of groundwater extraction on a spring and its dependent ecosystems is intrinsically linked to local-scale hydrology, the spring's source aquifer and the discharge environment. This information is critical in the assessment of impacts from groundwater extraction and resource development activities. Using a case study of the Lucky Last and Abyss spring complexes in the Surat Basin of the Great Artesian Basin (Australia), an approach was taken to identify the source aquifers and to build a local-scale conceptualisation. Field investigations, including surface geological mapping, investigation bores, water quality sampling and geophysics, were applied to reduce plausible hypotheses and to increase confidence in the long-term prediction of impacts on these springs. The report highlights advances in the hydrogeological conceptualisation of the Lucky Last and Abyss springs, as well as the benefits of applying an approach that involves hypothesis testing and multiple lines of investigation. The assessment provides increased confidence in the determination of source aquifers for springs in the Surat Basin, with the approach being applicable more broadly to the conceptualisation of springs across the Great Artesian Basin and other regional groundwater flow systems.