The Northern Australia Water Resource Assessment (NAWRA) was conducted by CSIRO, being the ‘most integrated, multidisciplinary investigation of opportunities for water and agricultural development in northern Australia’. The NAWRA was motivated and commissioned by the White Paper on Developing Northern Australia and the Agricultural Competitiveness White Paper, both of with are initiatives of the Australian Government.
Three catchments were investigated as part of the Assessment: the Fitzroy catchment in Western Australia, the Mitchell catchment in Queensland and a group of rivers that made up a Darwin catchment in the Northern Territory. For each study area surface and groundwater capture and storage options were identified and investigated, detailed land suitability and assessed potential impacts and risks based on multiple criteria.
The Mitchell catchment is most like the Gilbert, also flowing into the Gulf of Carpentaria. There are also shared aquifer formations between the Gilbert and the Mitchell. Surface water storage was suggested as the most viable option to support irrigated agriculture development in the Mitchell catchment, with both large in-stream dams and off-stream dams possible. Groundwater options were deemed small and localised. Managed aquifer recharge (MAR) was highlighted as a potential to augment groundwater recharge along ephemeral rivers (i.e., rivers that only run for part of the year). MAR has also been suggested as possible to supplement groundwater in the bed sands of the Gilbert River along the GRAP.
