Recharge estimation in the Surat Basin
This research measured for the first time the field recharge rates in representative type locations. It is being used for improved modelling confidence by The University of Queensland & the Queensland Government Office of Groundwater Impact Assessment (OGIA).
The amount of water (flux) entering an aquifer as recharge is a critical factor in determining how water table levels change, the sustainable yields for groundwater extraction, and the impact of extractive industries on groundwater availability. However, the processes that govern this flux remain difficult to quantify, and are therefore considerable sources of uncertainty in modelling the groundwater balance and conducting impact assessments.
Due to the geological complexity of the Surat and Bowen Basins, recharge can occur via multiple pathways along the basin margins, principally within the ‘intake beds’, where various geological strata come to surface outcrop, but other less direct pathways may also be important. The amount of recharge varies greatly both geographically across these different pathways due to physical and climatic factors.
This research seeks to improve understanding of these recharge pathways and the variation in rates (in both space and time) across the basin. The research has been designed as a three-stage project combining desk-top review, workshops, fieldwork, and modelling.
Phase 1: Desk-top review, workshops and modelling provided an update on current understanding of recharge and identified opportunities for targeted field measurements to be conducted in Phase 2 to reduce uncertainty.
Phase 2: Conducted fieldwork which established a monitoring network to link the surface and subsurface hydrology, providing new knowledge of recharge processes including transience. The recharge models, recharge estimates and guidelines developed in Phase 1 will be updated in Phase 3 to include this new knowledge.
Phase 3: Established recharge estimates based on the data from three field sites. Established deep drainages estimates (publication pending) and gathered data flow regimes. A PhD on regional deep drainage assessment is currently underway (ongoing).
PROJECT OUTPUTS
- Final Report (Phase 3): Documentation of revised recharge estimates and models, finalised estimation recommendations and associated training program.
- Final report (Phase 2): Report outlining experimental outcomes from field programs and revised estimation recommendations (complete).
- Final report (Phase 1): Recharge Estimation in the Surat Basin Stage 1 final report – A review of scientific progress in understanding recharge processes in the Great Artesian Basin intake beds; recommendations regarding recharge estimation methodology; design of a field work program for Phase 2.
- Conference presentation: Greg Keir, Nevenka Bulovic, Neil McIntyre (2017), Monitoring and modelling groundwater extractions over a data-sparse region of Australia, Australian Groundwater Conference, Sydney
- Research poster: Poster: Centre Research Review - estimation (2017)
- Research poster: Poster: Centre Research Review - regional (2017)
- Research poster: Poster: Centre Research Review (2016)
- Conference presentation: McIntyre N (2015) A multi-scale experimental and modelling program for estimating groundwater recharge in the Surat Basin, Australian Groundwater Conference November 2015.
- Conference presentation: Underschultz J (2015) Research Aiming to Improve our Forecasting of CSG Cumulative Impacts on Groundwater, Australian Water Association meeting June 2015
|