The objectives of hydrogeologically mapping the Murray basin were to generate a set of maps at 1:250 000 scale to: - show the influence of groundwater on land salinisation and surface water salinity - delineate useable groundwater resources - highlight present and potential salinity hazard and - enhance community awareness and understanding of groundwater systems and processes and provide a groundwater data-base for the Murray Basin to facilitate land and water resource management decisions. The production of the Murray Basin Hydrogeological Map Series was a major coordinated Government action in the management of groundwater to combat degradation through salinisation and enable sustainable land and water use in the Murray Basin. The Hydrogeological Map Series was a collaborative effort between the various water authorities of South Australia, Victoria and New South Wales. Explaining this product in detail is an article by Evans, W.R. 1992, "The Murray Basin Hydrogeological Map Series", Water pp. 20-23.

No abstract available

Broken Hill Managed Aquifer recharge Projects 3D models and Fly-through

The 'River Murray Corridor (RMC) Salinity Mapping Project', provides important new information in relation to salinity hazard and management along in a 20 km-wide swath along a 450 km reach of the River Murray. The project area contains iconic wetlands, national and state forest parks, irrigation and dryland farming assets and the Murray River, significant areas of which are at risk from increasing salinisation of the River, the floodplain, and underlying groundwater resources. The project utilised a hydrogeological systems approach to integrate and analyse data obtained from a large regional airborne electromagnetic (AEM) survey (24,000 line km @ 150m line-spacing in a 20 km-wide swath along the Murray River), field mapping, and lithological and hydrogeochemical data obtained from drilling. New holistic inversions of the AEM data have been used to map key elements of the hydrogeological system and salinity extent in the shallow sub-surface (top 20-50 m). The Murray River is known to display great complexity in surface-groundwater interactions along its course. Electrical geophysical methods (such as AEM) are able to map surface-groundwater interaction due to the contrast between (electrically resistive) fresh water in the river, and (electrically conductive) brackish to saline groundwater in adjacent sediments. The location of significant river flush zones is influenced both by underlying geology and the location of locks, weirs and irrigation districts. The study has also identified significant areas of high salinity hazard in the floodplain and river, and quantified the salt store and salt load across the floodplain. The study has also identified sub-surface factors (including saline groundwater, shrinking flush zones, declining water tables) linked to vegetation health declines.

Water resource assessment for the Great Artesian Basin. Synthesis of a report to the Australian Government from the CSIRO Great Artesian Basin Water Resource Assessment

The use of airborne electromagnetics (AEM) for hydrogeological investigations often requires high resolution data. Optimisation of AEM data therefore requires careful consideration of AEM system suitability, calibration, validation and inversion methods. In the Broken Hill managed Aquifer Recharge (BHMAR) project, the helicopter-borne SkyTEM transient EM system was selected after forward modelling of system responses and assessment of test line data over potential targets. The survey involved acquisition of 31,834 line km of data over an area of 7,500 km2 of the River Darling Floodplain. Initial FAI inversions provided within 48 hours of acquisition were used to target 100 sonic and rotary mud holes for calibration and validation. A number of different (Laterally and Spatially Constrained) inversions of the AEM data were carried out, with refinements made as additional information on vertical and lateral constraints became available. Finally, a Wave Number Domain Approximate Inversion procedure with a 1D multi-layer model and constraints in 3D (including boreholes), was used to produce a 3D conductivity model. This inversion procedure only takes days to run, enabling rapid trialling to select the most appropriate vertical and horizontal constraints. Using this approach has produced reliable, quantitative estimates of the 3D conductivity structure, and enabled identification of a diverse range of MAR options and groundwater resources. The hydrogeological complexity revealed by AEM mapping greatly improves the parameterisation of groundwater models, and provides a framework for understanding complex hydrogeological and hydrogeochemical processes that are critical to assessment of a range of MAR, surface water and groundwater extraction options.

Legacy product - no abstract available

Submission to the Parliamentary Joint Committee on the Australian Capital Territory concerning the inquiry into long-term collection and disposal techniques for Canberra city waste. In Canberra, solid waste is disposed of in open dumps and sanitary landfill sites. A major environmental problem resulting from such practice is the pollution of groundwater by leachate, and the monitoring of groundwater pollution is an essential part of landfill management that must be continued long after a site is closed. The selection of landfill sites depends on the physical constraints of geology and hydrogeology, but planners do not always sufficiently consider the physical constraints in the selection of landfill sites. The success of a landfill site depends mainly on site selection,and must be supported by good site management techniques and groundwater-pollution monitoring procedures. In many communities, public authorities maintain good land-fill practice by setting high standards for landfill operators, and by controlling the site through regulations and the supervision of monitoring procedures.

Under the Community Stream Sampling and Salinity Mapping Project, the Australian Government through the Department of Agriculture, Fisheries and Forestry and the Department of Environment and Heritage, acting through Bureau of Rural Sciences, funded an airborne electromagnetic (AEM) survey to provide information in relation to land use questions in selected areas along the River Murray Corridor (RMC). The proposed study areas and major land use issues were identified by the RMC Reference Group at its inception meeting on 26th July, 2006. This report has been prepared to facilitate recommendations on the Barr Creek - Gunbower study area. The work was developed in consultation with the RMC Technical Working Group (TWG) to provide a basis for the RMC Reference Group and other stake holders to understand the value and application of AEM data to the study area. This understanding, combined with the Reference Groups assessment of the final results and taking in account policy and land management issues, will enable the Reference Group to make recommendations to the Australian Government.

One of the primary requirements of managing our water resources sustainably is an understanding of the water balance. Key components of a water balance model are inputs of recharge and outputs or discharge. Rates of recharge and discharge change in response to climate, landscape morphology, geology, soil/regolith, native vegetation and landuse (including landuse history). The variable nature of these parameters results in a high degree of local variability when determining recharge and discharge fluxes both spatially and temporally. Water managers deal with this complexity in a variety of ways. Where detailed information on key parameters influencing recharge and discharge are available, comprehensive, fully distributed groundwater models are used. However, in most cases this information is not available (e.g. data poor areas) and typically a crude estimation of recharge (2-10% of average annual rainfall) is given. In these cases, discharge is often assumed to be zero. A collaborative project, funded by NWC and involving CSIRO Land and Water and Geoscience Australia, has developed a new national framework for estimating recharge and discharge in data poor areas. The approach consists of excel-based models that allow the user to populate key input fields (e.g. rainfall, soil and regolith texture, bedrock type, vegetation) to generate estimates of recharge and discharge. These excel models have been coupled with a complementary national-scale GIS dataset to assist the user in populating model input fields. In combination, the models and the GIS datasets allow the user to rapidly estimate recharge and/or discharge anywhere in Australia. The national-scale GIS datasets are available through a WEB-based interface. This presentation will focus on the development of the input datasets and will provide a brief demonstration of the WEB-based interface.