Fish & Game is calling for an independent review of Horizons Regional Council following revelations the majority of farmers are not meeting One Plan targets.
Horizons voted to implement the plan last year which after years of hearings, submissions and court cases introduced nitrogen leaching limits for intensive farming.
But so far 52 of the 61 resource consents under the One Plan do not meet the targets and have been issued as restricted discretionary consents. They've been issued for up to 20 years some at up to three times the limit.
Fish & Game New Zealand chief executive Bryce Johnson said it was disappointing the council was not following its own plan or court direction.
"Allowing river pollution to continue in defiance of the council's own plan just beggars belief," Mr Johnson said.
Fish & Game is a statutory body and supported the original One Plan all the way to the High Court, winning at every stage.
"Now Horizons thinks it can defy the courts and backtrack on promises and obligations its own plan places on it," he said.
"What Horizons appears to be doing now is grandparenting the right to pollute " something that was rejected by the courts," Mr Johnson said.
The Environment Court said grandparenting was "allowing existing operations to continue to leach nutrients at rates based on their own historical performance" and "should not form part of the rules regime".
Mr Johnson said Fish & Game was now considering a variety of options.
"Horizons Regional Council needs to be reviewed, judicially if necessary as all the indicators are that it is now not implementing the Environment Court and High Court judgments."
But Horizon's Wanganui-based councillors held no concerns. "I knew what was going on," councillor Rod Pearce said. "I knew there was a opportunity for dairy farmers to phase down their nitrogen outlet." Mr Pearce believed there would be significant decreases in nitrogen reaching the water. "That's as far as I can go with it," he said. "I think we've got to be talking to the professionals about that.
"With all due respect to them (Fish & Game) they do tend to stir the pot from time to time. I don't mean that as any criticism of them."
Councillor David Cotton said it was practical to give farmers time to meet compliance and was happy with the council's approach. "They are going to have to meet compliance over a period of time. If you make these people go broke, what does that achieve?"
But Mr Johnson said Fish & Game had spent substantial resources to protect rivers for the whole community, not just its licence holders.
"It is time Horizons faced up to its responsibilities and started putting the environment first ahead of economic expediency, as the law requires it to do."
The Environmental Defence Society also wants to talk about Horizons' consenting process. "The concern is the council, and I'm aware regional council politics are always fraught, may be going soft on implementing the plan," chairman Gary Taylor said.