CSIRO has been assessing water and land resources across northern Australia for decades. Over the last 15 years, we have focused on priority catchments across the north. These comprehensive assessments quantified the opportunities for water-related developments, increased understanding of the constraints to development, and established a unique baseline of data for large parts of northern Australia. We evaluated landscapes that are vast, remote and data sparse by using novel techniques that blended numerical modelling, remote sensing and ground-based measurements. Our work has informed and responded to the 2015 northern Australia white paper.
We found that:
• Each catchment is physically unique.
• Irrigation development is mostly constrained by lack of water rather than suitable soil.
• Although landscapes are largely intact, they are not pristine – catchments can support a maximum 1–2% of their area under irrigation.
While our focus catchments are sparsely populated, they are home to many Indigenous people, including some of the most disadvantaged communities in Australia. Indigenous people have occupied and managed these landscapes for tens of thousands of years. Despite the impacts of colonisation, they have secured significant legal recognition of their rights and interests in land and water resources. They have crucial roles in future water and development planning and as co-investors in future development. Any future development would depend on community and government accepting potential impacts to ecosystems and existing users. Irrigated agriculture in northern Australia is only likely to be financially viable where good prices for high-value crops align with market advantages, making it challenging to achieve scale. In most catchments, rain-fed cropping would be opportunistic and depend on farmers’ risk appetite and future local demand, keeping in mind that changes in climate may mean a drier future. Our paper concludes with next directions and future priorities for research in northern Australia.