Broken Hill managed aquifer recharge

Project completed 2012

Background

The Broken Hill Managed Aquifer Recharge (BHMAR) project investigated groundwater-related options to help secure Broken Hill's water supply during drought; reduce evaporation and improve water efficiency at the Menindee Lakes Storages; protect the local environment and heritage; and return up to 200 gigalitres (GL) of water to the Murray-Darling Basin.

Satellite image of the Broken Hill Managed Aquifer Recharge project area in the southern half of Eastern Australia.

Location of the BHMAR project
area (purple line) spanning a portion
of the Lower Darling valley within
the Murray Geological Basin (green line)
and the Murray-Darling river catchment
area (white line)

The project was a key element of the Federal Government's 2007 election commitment to improve the management of the Menindee Lakes area in far western New South Wales. The project was managed by the (former) Australian Government Department of the Environment.

In southern Australia, recent droughts and predictions of a drier future have led to innovative strategies to improve water security for regional communities and industries, while also delivering environmental benefits. Of particular concern is the Murray-Darling Basin, where the Millennium Drought adversely affected many communities, industries and the environment. Although heavy rains and flooding broke the drought from late 2010 onwards, longer-term strategic solutions are needed to protect communities against future droughts and achieve a healthier Basin.

Outcomes

Beginning in 2008, the BHMAR was the largest hydrogeological investigation undertaken by the Australian Government for over 30 years. This innovative project delivered outcomes to improve water security by using aquifers during drought periods to reduce dependence on surface water resources. Key findings from the BHMAR project included:

  • Identifying a priority site (Jimargil) that could provide enhanced drought security for Broken Hill. There are several groundwater-related options at this site. These take a conjunctive approach to water management by using surface water when it is abundant and relying on groundwater extraction during drought conditions.
  • Groundwater supply options would provide significant water quality benefits for the Darling River and water supplies for Broken Hill and Menindee during drought periods. This would also enable changes to the Menindee Lakes Storage to provide substantial water savings with significant downstream benefits in dry years.
  • Discovering potential groundwater resources beneath the Darling River floodplain at Menindee Lakes. These resources are estimated to contain between 2100 and 4400 gigalitres of fresh to acceptable quality groundwater in 14 discrete targets at depths of 25 to 125 metres below ground. These estimates are for total aquifer storage and do not represent the amount of groundwater that could be sustainably extracted (which would be significantly smaller).

Outputs

The Summary Report (report 5) includes key findings and recommendations for potential groundwater resource option across the BHMAR study area, and possible alternative water supply options for Broken Hill. This report is supported by four scientific and technical reports (reports 1-4).

All reports are available as free digital downloads.

Supporting data, analytical, interpretation and product generation methods are included in fifteen accompanying appendix volumes (Apps et al., 2012). Project data and products are also available in the BHMAR project GIS data package (Gow et al., 2012a).

The final project reports were reviewed by scientific experts from Geoscience Australia and the CSIRO. External reviews were undertaken by independent consultants within Australia, as well as an expert panel from the United States Geological Survey (USGS). The project was guided by a Steering Committee with representatives from the Australian and NSW governments.