"We acknowledge a flow-on effect. But I will not set a royalty that will affect other parts of the industry until I have sat down with them and worked out a workable plan that ensures they remain profitable and that it is fair."
Not all farmers will be captured by the policy because the royalty will vary according to water quality, scarcity, and what it is being used for. The highest charge will be for bottled water taken from pristine aquifers and exported.
Although Ms Ardern assured she was committed to working collaboratively with farmers to find a "workable solution" which would ensure they prospered, this has not quelled fears for those in Hawke's Bay's primary sector.
Horticulture Hawke's Bay president Lesley Wilson said while she needed to look at the policy's details to see how much it affected growers, "the implicit assumptions that it is irrigators that are causing issues with water quality and quantity is flawed.'
"As with all costs associated with growing, they are absorbed into the price to the consumer, so while the Labour policy is to tax growers, essentially those costs will be borne by the consumer in the price of food," she said.
'We would like to see good science used to solve the issue surrounding water quality and quantity, we do not believe this additional tax will contribute to that'
Her concern was echoed by Federated Farmers Hawke's Bay president Will Foley, who said it would place more costs on to farmers, meaning the consumer would have to pay more.
"It could drive farm policy. [Farmers] they could say it's going to cost us more, we're going to have to change our practices and potentially intensify to try and get a better return on whatever it is they're farming to match those increased costs."
Although he was glad Labour would be consulting on a rate, he thought the regions' farmers would be "pretty worried and concerned" about the proposal.
"The real concern is where it's going to end up, but it seems to just be targeting water bottlers and farmers so I guess the question probably is why those two industries are just getting targeted and no one else," he said.
Labour's water policy also promised changes to farming models, saying that farms near waterways would have to move away from high stocking levels and focus more on "adding value".
It sets a five-year deadline for farmers to fence off all intensively stocked land near waterways. To assist farmers, Labour would get youth to help out with fencing, riparian planting and other measures to improve water quality.