Watertable rises resulting from irrigation are evident in several areas in the Murray Darling Basin, with groundwater level rises of up to 70 cm per year being reported in the Riverina and 50 cm in the Lower Macquarie Valley. The Department of Water Resources initially reported rising groundwater in the Lower Macquarie Valley about 7 years ago, and it was predicted that large areas north and west of Narromine may become waterlogged within the next 15 - 25 years. Current aquifer pressures indicate watertables may rise to within 2 m of the soil surface in some areas, eventually resulting in salinisation. Groundwater recharge in the Macquarie region seems to be effected by a number of factors including; floods, seepage from the river bed; leakage from weirs; storage dams and irrigation channels; and intensive irrigation. The aim of this study was to identify potential rates of groundwater recharge under irrigated cotton.