Development of a method to correct for hydrostatic pressure changes on adjacent aquifer responses
Project details
| Objective: | To improve our understanding of aquifer interactions and the issue of aquifer unloading |
| Funding: |
$160,000 plus GST |
| Jurisdiction: | National |
| Commences: | January 2009 |
| Completed: | November 2010 |
About the project
In many areas of Australia, and especially in the Murray-Darling Basin, groundwater is pumped from a deep confined aquifer, while the overlying shallow unconfined aquifer is not exploited - typically because of poor water quality.
Large-scale groundwater extractions across the deep aquifers of the Murray Basin Riverine Plain since 1995 have led to reduced groundwater levels in these aquifers. However, it is possible that some proportion of the overall decreases in deep aquifer pressure could also reflect reductions in weight of overlying shallow water tables (defined as 'unloading') due to drought and decreased irrigation.
This project will contribute to better understanding of the connections between deep and shallow aquifers, by investigating aquifer pressure reductions and subsequent level changes and developing a method to correct for hydrostatic pressure changes on adjacent aquifers.
Project benefits
This project will study the range of possible deep confined aquifer pressure responses as a result of the unloading of the shallow water table.
Outcomes of the project will be:
- an understanding of the importance of unloading as a process influencing groundwater pressure change
- a methodology to adjust groundwater hydrographs for unloading
- a quantification of the significance of unloading in overestimating the available groundwater resource.