Before and after aquifer development: A rare history of a large spring complex in the Great Artesian Basin, Australia

• Springs diminished in the Great Artesian Basin, Australia because of extraction. • This study provides a rare example of a spring baseline flow prior to extraction. • Elizabeth Spring diminished to 9 % of original flow. • Elizabeth Spring has recovered 33 % of original flow with pressure recovery. • This quantified report has positive lessons for global aquifer management. Natural springs have declined in the face of groundwater extraction. Accurate assessment of the impact of pressure decline on spring discharge is difficult to determine because of uncertain historical baselines. A novel historical record for Elizabeth Springs, a spring in the Great Artesian Basin of Australia is presented and compared with flow rates from 1951 to 2022. A government hydrologist used V-notches on drains to estimate a flow rate at Elizabeth Springs in 1896 prior to extensive development of flowing bores in the region. Since this time free-flowing bores have resulted in a decline of aquifer pressure reaching its lowest value in 1998. With the rehabilitation of bores by capping and piping, pressure has recovered more than 10 % by 2019. Flow rate from the springs was estimated using vegetated wetland area and evaporation rate. The discharge from Elizabeth Springs reached its lowest value in 1981 and increased 3-fold by 2022. This study provides an important case study demonstrating the use of historical sources to determine a baseline of spring flows prior to extraction. The response of the aquifer to bore capping at Elizabeth Springs is delayed compared to another similar recent assessment near the eastern margin of the Eromanga Basin. This delayed response may be explained by the less permeable sandstone in the aquifer underlying Elizabeth Springs. Further pressure recovery is expected at Elizabeth Springs. The findings represent a critical report of pressure recovery and a demonstration of aquifer management with global implications. Reduction of profligate groundwater use and restoration of aquifers and springs can be achieved, while allowing sustainable groundwater use.