Suggestions that farmers should be taxed for water use ignores the fact that irrigators are already paying for the water they use.
Irrigation New Zealand calculates the average cost of water supplied by irrigation schemes every two years, and in 2016 the average cost was $780/ha/year - 14 cents/cubic metre.
However, this figure only includes the infrastructure required to take and supply the water. The cost of the infrastructure onfarm and increased rates - because irrigated land is of higher value - is extra. For example, a 100ha irrigated sheep and beef property pays at least $2000/year more in rates than the equivalent dryland property.
On top of this, farmers also pay for the monitoring and reporting on water use done by local councils every year and to improve their environmental performance so they comply with environmental limits.
It makes no sense to impose a water tax on one sector when we all use water. Everyone in NZ benefits from water so common sense would say a water tax should be applied to everyone who uses it.