Gravity has powered the distribution of water in agricultural districts for millennia. Enhanced by Australian innovations, several large-scale gravity-fed irrigation networks are now delivering water to farms more efficiently, leading to improved productivity of limited water resources.
The University of Melbourne has worked with gravity-fed irrigation specialist Rubicon Water for more than 15 years. An outcome of this collaboration is the commercial technology called Total Channel Control (TCC) for automating the operation of open-channel irrigation systems.
In Australia, TCC has been adopted throughout Victoria’s Goulburn Valley and parts of the New South Wales Riverina. Rubicon technology is also in use internationally, with installations in the US, China and New Zealand.
Over the past few years, TCC systems have delivered hundreds of gigalitres of water, through thousands of kilometres of channels, with efficiency gains recovering water for further use.
Professors Michael Cantoni and Erik Weyer at the University of Melbourne’s Department of Electrical and Electronic Engineering have been involved with much of the research that underpins TCC’s automation capabilities.
The system relies on a radio network of sensors for measuring flow and water levels and actuators for controlling flow at different locations along the channels. The sensor information is automatically processed online to dynamically adjust actuator settings to match the flows required to meet demand.
Automation has been the key to reducing the lag between water ordering and delivery from weeks down to hours, which gives farmers greater flexibility. Automatic control also underlies distribution efficiency improvements, which make more water available for additional irrigation or sustaining environmental flows.
Water is fundamental to everything we do, says Professor Cantoni.
Food production pressures call for improvements on many fronts, including the efficiency with which we distribute the water.
He and Professor Weyer are also leading new projects to expand and enhance the automatic control systems at the heart of Rubicon’s world-leading technologies. New research will develop automation systems for low-energy closed-conduit networks. Professor Cantoni says this poses new challenges in modelling and control. However, the benefits of pipes – lower maintenance and lower losses dues to leakage and evaporation – make them an option worth considering for irrigation network expansion or the replacement of small channels.