A farming leader says "large amounts" of farming will have to go if the Government's plan to clean up waterways becomes law.
The plan would put major restrictions on farm intensification and water standards, and seek to markedly improve New Zealand's waterways within five years.
The issue is open for submissions, but Federated Farmers environment and water spokesperson Chris Allen has told TVNZ1's Q+A the strictest suggestions in the policy document will require massive change on the farm.
"That would mean basically taking away large amounts sheep and beef farming off the Canterbury plans, a lot of dairy farming would have to go," Mr Allen said.
"Now if that's what the community wants, I've got to think about the community of Ashburton or Matamata, Mataura, in saying holy hell what can we do to get there? Because we've got to all go on this journey," he said.
"And it's not that we don't want to go to the same place, we're just saying is that particular bottom line going to get us to where we all want to go to?"
Asked are there parts of country where pastoral farming may no longer be viable, Mr Allen said, "Pastoral farming, vegetables. There's so many things that are required with the nutrients that we need. And look, any farm that loses nutrients is not a good idea. And we've got to have all the tools to keep that on the land."
These goals are very consistent with what New Zealand as a whole want- Marnie Prickett, Choose Clean Water NZ
Marnie Prickett of environmental group Choose Clean Water NZ said there is support for farmers worried about their livelihoods "to change and transition", with Government money in a transition fund.
Ms Prickett called on farmers "to turn back to their leadership, particularly dairy industry leaders" who she said encouraged farmers to "intensify in the wrong places". She said people were saying 20 years ago it's not a good idea to intensify dairy in Canterbury because it would harm waterways.
She said the Government's current proposals are "really promising" and provide the opportunity to deliver on Labour's election promises.
"They talked about swimmable rivers and healthy rivers within a generation. And more recently we've heard the Government say that they want to see material, noticeable changes in water quality over the next five years. And these goals are very consistent with what New Zealand as a whole want. We know that this is a big issue," she said.
"The stronger options are where we want to land here. So I'd like the Government to resist the pressure from those who want to protect agricultural polluters, those really high nitrogen leachers," Ms Prickett said.
Mr Allen said he accepts "there's been quite an impact from some of our farming activities on some of our waterways".
But he said but many waterways are pristine and meet the standards, with low nitrate levels.
Interviewer Jack Tame produced figures showing that in pastoral areas 86 per cent of New Zealand rivers exceed guidelines for nitrogen standards and 90 per cent exceed them for phosphorous.
Mr Allen replied that some of the main rivers through Canterbury are pristine in water quality, though lowland streams are most vulnerable where a lot of agriculture is located.
There are some "hotspots" where "we've got to target our activities" to improve water, he said.
* Q+A is on TVNZ1 on Mondays at 9.30pm, and the episode is then available on TVNZ OnDemand and as a podcast in all the usual places.