18 th World IMACS / MODSIM Congress, Cairns, Australia 13-17 July 2009 http://mssanz.org.au/modsim09 Water saving through smarter irrigation in Australian dairy farming: Use of intelligent irrigation controller and wireless sensor network Dassanayake, D. 1, 2 , K. Dassanayake 3 , H. Malano 1 , G.M. Dunn 3 , P. Douglas 1 and J. Langford 4 1 Department of Civil and Environmental Engineering, The University of Melbourne, Melbourne, VIC, Australia 2 Department of Forest and Ecosystems, The University of Melbourne, Melbourne, VIC, Australia 3 Department of Land and Food Resources, The University of Melbourne, Melbourne, VIC, Australia 4. UNIWATER, The University of Melbourne, Melbourne, VIC, Australia Email: dharmad@unimelb.edu.au Abstract: Precise control of irrigation water for improving water use is critical for sustainability of irrigated farming systems under Australia’s present water crisis scenario. Border-check irrigation is the predominant method of irrigating dairy pastures, which is the single largest water user in the country. As a classical practice of border-check irrigation, cut-off of the water supply is determined when the waterfront reaches two third of the irrigation bay. In these practices, irrigation requirement may not have fulfilled or there may be increased deep percolation and/or water logging, which lead to lower economic water and pasture productivity. In order to address these issues, a sensor based border-check irrigation system (Real Time Intelligent Irrigation Controller - ARTIIC) has been developed that includes a real time feedback control. The system consists of a wireless sensor and actuation network, a central host/user interface, which collects stores and displays real time information, and central control system software. ARTIIC, which analyses data and reports in real time, plays a dual role scheduling and monitoring irrigation events. ARTIIC has two main components Automated Real Time Controller (ARTC) and Intelligent Irrigation Controller (IIC). A wireless sensor network (WSN) comprised of probes/sensors was installed in a trial dairy farm located in Dookie, Northern Victoria, Australia, to capture and store data in real time into a SQL Server database at a set uniform time interval. This paper describes the core component, Intelligent Irrigation Controller (IIC) of ARTIIC, which uses and analyses data downloaded by the WSN. IIC can make event based unsupervised estimation of irrigation parameters and runoff using a kinematic wave model, based on a linear infiltration model and the Manning Equation followed by unsupervised estimation of optimal time to cut-off, which is then passed to ARTIIC. Unsupervised features of IIC is capable of facilitating automation in the real time control environment. The new irrigation control of IIC is currently under evaluation at the trial farm in Dookie, and initial results indicate up to 43% (average 38%) water saving over conventional irrigation control methodologies. In this paper authors are focusing on IIC, which is the core model that facilitates the irrigation control. Keywords: Wireless Sensor Network, Border-check irrigation, Irrigation parameters, Time to Cut-off, water saving, Intelligent Irrigation Controller, Automated Real Time Intelligent Irrigation Controller, IIC, ARTIIC. 4409