The government has delayed bringing in regulations to control the controversial practice of intensive winter grazing after pressure from the farming industry.
Winter grazing is when livestock are kept in small sections of pasture until they completely finish off the crop and are at times, cramped and wallowing in mud.
The regulations to improve waterways and animal welfare were supposed to come into effect from May, but the government has deferred it until 2022.
Farmers had complained that the restrictions and requirements were impractical.
However, Environment Minister David Parker said farmers had agreed to make immediate improvements as a compromise for the delay.
Until May 2022 they had been asked to follow a farm plan.
"We are going to spend this year with the sectors testing the deployment of a prototype IWG module.
"I've got a commitment from the sector and regional councils to drive clearly demonstrable, real practice change this winter grazing season."
He said farmers had already been given a lot of help to make these changes, and it was the primary responsibility of those causing the pollution of rivers to clean them up.
The industry groups and regional councils had been asked to do more monitoring and provide a quarterly report on progress to the minister.
But the Greens have accused the government of caving to agri-business by delaying the regulations.
Green Party environment spokesperson Eugenie Sage said Parker was sending the wrong message to farmers.
"The government's reliance on a voluntary approach by farmers, rather than enforcing rules to control harmful intensive winter grazing, is a 'hope and pray' approach to healthy rivers," she said.
"There are many farmers who are at the forefront of improving farm practice and who recognise the realities of a changing climate and polluted rivers. They recognise that such intensive stocking and grazing has to end. We should bolster those farmers who want to reduce pollution and keep animals healthy, rather than allowing this practice to continue."
Sage said the decision risked another winter of avoidable pollution and increased emissions from overstocking.
"Alongside this pollution, cows will suffer in tough conditions, cramped and wallowing in mud where they can't lie down comfortably," she said.
"There has been concern about the impacts of intensive winter grazing for decades now. We know that some farmers are making a change, but there's always the tailenders who aren't. That's why we need rules."
Greenpeace said the government's delay in implementing already-weak intensive winter grazing regulations was yet another example of them buckling to New Zealand's "dirtiest industry".
"Leaving a bad practice unregulated and thanking industry for their promises to make it slightly better is no substitute for getting rid of it, as the Government should be doing with intensive winter grazing."