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Land affected by a high water table displays waterlogging and salinity effects. This causes costs to farmers through additional land management problems, loss of soil productivity and results in a decline of the farm's capital value. A multi-period mathematical model is developed to investigate best land and financial management strategies for such farms. Water tables rise mainly due to ground water import caused by high recharge in the surrounding parts of the catchment. The hydrological connection between model farm and catchment is established through the variable "condition of the upper aquifer". This paper analyses the effects of different levels of ground water import in terms of progress of soil salinisation, associated farm management responses and farm income development. The condition of the upper aquifer is shown to be decisive for the advance of salinisation and for the financial viability of the model farm. If the upper aquifer is draining or if it causes only minor rise of the water table, then the farming enterprise remains viable and long-term sustainable. If the aquifer condition causes high rates of upward leakage, then salinisation erodes farm productivity to an extent where no financially viable land management strategy is available.