Federated Farmers and Horticulture New Zealand have failed in their bid to stop Horizons Regional Council's One Plan becoming law.
A High Court appeal of the Environment Court approval of the plan, which will set nitrogen leaching limits on farms, has been lost.
Justice Stephen Kos turned down all but one of the farmer bodies' points of law, allowing one minor change to wording in a clause about erosion.
Horizons chairman Bruce Gordon welcomed the decision and said it had gone "pretty much as we expected".
And now that's dealt with, we can finally start cleaning up our river. And the precedent set here will hopefully encourage other Regional Councils to enact similar measures to protect water quality - which is what Federated Farmers is really afraid of.