Brackish groundwater characterisation project: a Western Australian case study

Project overview

Groundwater can be fresh enough to drink, or saltier than the sea. Brackish water has some dissolved salts but is less salty than saline water.

Most groundwater studies in Australia have considered freshwater resources. But Australia also has a large quantity of brackish and saline groundwater. It could be possible to use saline or brackish groundwater in areas where freshwater is scarce. It can be mixed with other water resources or treated to remove salts before use.

This project is examining the locations and characteristics of brackish groundwater resources. It is also exploring whether brackish groundwater may be used for different purposes. It is assessing whether desalination and other treatments are practical. The project also assesses whether these treatments are cost-effective and sustainable. Western Australia is the pilot area for this project.

Goals of the assessment

This project aims to progress the potential use of brackish groundwater resources. This may increase water security or provide water for sustainable economic development.

The CSIRO is exploring, mapping and characterising brackish groundwater resources. The initial focus is on Western Australian aquifers. The project is also considering the uses of water of different qualities and saltiness. The project also looks at treatment requirements for different uses.

The assessment will:

• examine the chemical composition, groundwater characteristics and behaviour
• examine the suitability of brackish groundwater resources and aquifers for development
• explore the feasibility and economic viability of using brackish groundwater, including pre-treatment requirements and available desalinisation technologies
• assess opportunities for using renewable energy supplies for the desalination process
• consider management options for brine produced as a waste product of desalination
• investigate the water quality suitability required at different locations.

This project could show broader use for this little-known resource. It could also pave the way for a national evaluation of the possible uses of brackish and saline groundwater.