The Goyder Institute for Water Research project on Sustainable Expansion of Irrigated Agriculture and Horticulture in Northern Adelaide Plains has made significant progress in recent months, establishing baseline data and models that will provide a basis for ongoing investigations. This has included establishing baseline conditions of the soils; constructing nutrient and chemical fate models; reviewing the quality and quantity of source water options; and comparing different techniques for a rapid method of estimating shallow groundwater depths.
This work will be further developed over the next 12 months and will be used to identify where water can be a trigger for the next generation of agricultural and horticultural development and how water supplies in the Northern Adelaide Plains can meet potential demand. This will include the development of environmental risk maps based on baseline status of the soil and the key water quality constraints for the different sources of water being considered for use. Simply said, the project will identify ‘what can be grown where’ and ‘how environmental issues affecting long term sustainable use can be overcome’.
The project is being led by Prof Jim Cox from PIRSA-SARDI and is a collaboration between PIRSA-SARDI, CSIRO, Flinders University and University of South Australia. Further details on progress for the project tasks can be found below.
Development and optimisation of modelling domain and impact assessment of irrigation expansion on the receiving environment
Progress has included:
Modelling nutrient and chemical fate, including salinity/sodicity risk, as the basis for identifying longevity of recycled water utilisation and mitigation strategies under current and future climate
Source water options
A review of the quality and quantity of source water options has been undertaken, with source waters including:
Assessment of Depth to Groundwater (Proof of Concept)
Progress has included the completion of hydrogeophysical field work (photo, below) with frequency and time domain electromagnetic induction (nano-TEM), electrical resistivity tomography (ERT), and ground penetrating radar equipment in two locations.
Initial results suggest that the nano-TEM and ERT surveys map the groundwater conditions better than the other (frequency electromagnetic induction and ground penetrating radar) techniques. The derived depths to groundwater will be used in Task 2 as lower boundary condition for the HYDRUS-1D model.