The importance of water security to the development of northern Australia is well recognised. The recent completion of Rookwood weir in the Fitzroy River, Central Queensland, provides an example of the successful development of new water supply infrastructure in northern Australia. While water supply infrastructure plays a significant role in achieving water security, structures such as dams and weirs have the potential to impact on water quality and aquatic ecosystems. Environmental monitoring programs aim to measure these impacts so that they can be effectively managed, underpinning a sustainable approach to water security.

A water quality monitoring program was a condition of the Australian Government approval of the Rookwood weir project. To meet this requirement, a wide range of water quality parameters are regularly monitored upstream, within and downstream of the impoundment area. Long travel times to remote sampling sites and the quantity of laboratory analysis required result in high monitoring costs, and there are health and safety issues associated with manual water sampling during flood events in large rivers like the Fitzroy – challenges that are common in northern Australia.

As part of the CRCNA Water Security in Northern Australia (WSNA) research program, we are investigating options to streamline water quality monitoring in rural and regional areas. Such options include deploying continuous monitors and automatic samplers at difficult sites, accessing technological advancements in remote data collection, better targeting specific chemicals (such as pesticides) for testing based on farm records or land use management plans, and using mathematical approaches to extrapolate for data gaps.

In this presentation, we describe the water quality monitoring and reporting program developed for Rookwood weir, the potential for optimising monitoring to retain effectiveness while improving cost efficiency, and how similar options may be relevant to future water supply developments in northern Australia.