Oral Presentation Australasian Groundwater Conference 2017

Objectives

NZ is funding a joint NZ-EU research programme (SMART Aquifer Characterisation) to assemble and validate a suite of innovative methods for characterising the nation’s groundwater systems, at the national and aquifer scales. 

Focus of the research is on four key technical information gaps:

• Refining groundwater volume estimation
• Determination of aquifer hydraulic properties
• Quantification of fluxes between GW&SW
• Groundwater age-dating

This essential information, needed to effectively manage NZ groundwater resources, is lacking because traditional methods for aquifer mapping and characterisation are time-consuming, costly and ill-suited to large-scale application. The programme emphasis techniques that use passive data sources, which rely on existing data sources, or new measurements that can be made over large areas with reduced cost.

Methodology

The programme trialled methodologies in geophysics, satellite remote sensing, temperature-sensing and novel age-tracers. Validation via multiple methods applied in selected case study areas and ground-truthing. A framework was developed for quantifying uncertainty in each method, and optimising combinations of traditional and SMART.  Techniques were established to synthesise and visualise the datasets. A web portal and harmonised 3D groundwater database was developed to meet stakeholder needs for open access, ease of use, and interoperability with existing database systems.

Results

Highlights to date include:

• Satellite derived nation-wide long-term time series of groundwater recharge;
• Novel groundwater age tracers lead to better insight into groundwater flow;
• Temperature sensing techniques map groundwater-surface water interaction on multiple spatial scales;
• Reinterpretation of helicopter geophysical data to map aquifer-relevant lithologies across Otago;
• Standardised data transfer and communication protocols increases efficiency of data use.

Conclusions

A key component of the SAC programme is effective communication with water managers to ensure uptake of methodologies and results. This presentation also discusses how NZ end-users and stakeholders have been involved throughout the programme and the avenues used to ensure research is relevant and utilized.