One third of global food and fibre is produced by irrigation agriculture and it is predicted that this will rise by 50 % in 2040 (Rhoades et al. 1992 ). Management of the irrigated land is therefore an important factor in ensuring sustainable production. However, in the Murray-Darling Basin of Australia, inefficient irrigation practices have resulted in the creation of perched water tables, waterlogging, rising water tables and salt mobilisation. In NSW alone 40% of irrigated areas is prone to shallow water tables and this is increasing (Murray-Darling Basin Commission, 1999 ). The common cause of degradation is deep drainage (DD) or groundwater recharge, which is the process whereby water passes through the root-zone into the water table. With the increasing pressures on water resources and expectations from the community regarding natural resource management it is necessary that methodology be developed for identification of where salinisation has occurred, what are the processes, which have created these problems and determine where improvements can be made in natural resource management.