Land and Water Link

Issue No. 11, December 2001

A collaborative initiative in Queensland is helping build the lower Burdekin's reputation as a dynamic regional economy by studying the long-term impact of current water use on the region's water resources. With support from a range of national and state agencies and regional industry bodies, representatives from local community, industry and government are working together with researchers to ensure a sustainable future for the Burdekin's groundwater systems.

A Townsville-based research team, led by CSIRO Land and Water scientist Dr Keith Bristow, is contributing by investigating the linkages between land management practices and the response of the underlying aquifer systems - part of the quest to understand and properly manage overall water resources.

To date, industry and communities in the Burdekin region have reaped the benefits of local groundwater systems with few restrictions on access to water. However, questions are being raised about the long-term effect of current management practices. In particular, care is needed in protecting the aquifer systems from excessive loading of soil-applied nutrient and chemicals. It is also vitally important to ensure that there is no inland migration of the saltwater wedge, which separates the salty ocean from the freshwater supplies of the underground aquifers.

'The aquifer is the heart of the system and its good health has been one of the main contributing factors to the Burdekin's success as a major sugar producer. If we harm the ground-water system then we may endanger the economy of the whole region', warns Dr Bristow.

Over the next three years, CSIRO researchers will monitor water leaving the rootzone and entering the aquifer at several sites across the lower Burdekin. This work, combined with input from a range of other researchers and users working within the Lower Burdekin Initiative, will develop a better picture of the overall health and long-term sustainability of the Burdekin's groundwater and associated water systems.

The Lower Burdekin Initiative provides a framework to help facilitate communication, co-ordination and integration of the various water-related research projects underway in the region. As part of the drive to improve water use efficiency, the Queensland Rural Water Use Efficiency Initiative is working closely with farmers in the region to finetune their irrigation methods.

Irrigation development officer Peter Sutherland, who works with the Bureau of Sugar Experiment Stations in Brandon, has been analysing farm River and Irrigation Hydrology together with the farmers, and suggesting changes that could make a big difference. Most of the advice involves altering flow rates and the timing of irrigation. As Peter Sutherland has found, in some cases small changes to the way water is managed can lead to large improvements in crop returns.

While projects like these may lead to less water extraction from the aquifer, CSIRO's Keith Bristow explains 'we still don't know how the system will respond to these or other changes, especially in the longer term'.

Dr Bristow stresses that 'we must have a clear view of the big picture to see how the different components of the water balance fit together, and how changing one particular component will influence other components and impact on the long-term health of the groundwater system'.

'By working together to understand how the lower Burdekin water systems function, we can develop water management strategies that everyone understands and is keen to implement. The Lower Burdekin Initiative is an ideal vehicle to progress these issues.'

For more information: Refer to the LBI website Or contact

Dr Keith Bristow
Ph: (07) 4753 8596
keith.bristow@csiro.au