Deep drainage varies considerably depending on soil properties and irrigation management, and is not necessarily ‘very small’ - 50-100 mm/yr is typical, though 0 to 900 mm/yr has been observed.

Several recent experiments at ACRI, Narrabri have illustrated the fate of N fertiliser in irrigated cotton cropping.

Deep drainage below irrigated crops wastes a scarce resource and can potentially lead to rising water tables and salinity.

Deep drainage below irrigated crops wastes a scarce resource and can potentially lead to rising water tables and salinity.

Final report Quantifying deep drainage in an irrigated cotton landscape