The proposal by some politicial parties to put a charge on irrigation water has brought a further flood of criticism from political opponents and irrigation interests.
The Labour Party is proposing a resource rental, which would be used to help pay for irrigation schemes.
The Green Party is also proposing a charge on water used for irrigation and would use the proceeds for water pollution clean-up initiatives.
Industry body Irrigation New Zealand said taxing irrigation users in those ways is unfair, will not solve water quality issues and will encourage, not reduce, land intensification.
The ACT Party is calling for the introduction of tradable water permits instead.
ACT rural affairs spokesperson Don Nicolson said taxing the use of water is misguided as it overlooks the fact that not all irrigation water is from rivers.
"The best way to establish the true value of water is to set up a system of tradable water permits. That happens in some instances now where there is a grey market in water permits, but if the Green Party really want to do something useful, they would support that sort of system where you get the true value established.
"It's a cynical approach by the Greens to try and tax water over a select group of indivdiuals and that's all it is, cynical taxing."