Most profitable use of irrigation supplies: A case study of the Bundaberg district

A range of biophysical and financial factors, including the crop response to available water and the cost of irrigation, significantly impact on the economic benefits from using irrigation. Research tools have been developed in a multi-disciplinary environment to allow for the assessment of the economic benefits associated with using irrigation. This paper adopts the 1996-1997 season in Bundaberg as a case study and develops arguments for best use of limited water based on current economic and biophysical modelling capability. Irrigation 'options' were chosen for investigation based on combinations of soil type, allocation, critical fraction of available soil water (FASW) to irrigate, irrigation amount, and age of crop for irrigation commencement. The influence of these options on cane production is explored in a farm-level linear programming model. There appears to be a sound economic argument for further research into the crop response to irrigation, based on the sensitivity of farm incomes to choice of irrigation strategy, water availability and application cost.