Where is All the Water?

Australia has a very unique climate and water is one of its most precious resources. The Where is All the Water? project is a multi-disciplinary research collaboration that has shown for the first time that low-cost sensor networks in combination with other technologies can respond to the Australian infrastructure problem of great distances and low population. It demonstrated that local gravity measurements - soon likely to be augmented with quantum sensing capability - are a technology that can help us map the underground and assist with quantifying recharge to the groundwater; and that satellites have an important role to play in the management of resources. Overall, large uncertainties are identified in water accounting, with the interaction between surface and groundwater being one of the major sources of uncertainty. Thus, innovative solutions to quantify the fluxes between above and below ground remains a priority.