A Thames farming company ordered by a judge not to milk until a new dairy effluent system was installed is back in operation.
Tuitahi Farms was convicted in the Auckland District Court and fined just over $47,000 on four charges laid by the Waikato Regional Council.
Judge Jeff Smith called the offending long-term and insidious.
The council said it first spotted problems on the farm following aerial monitoring in September 2013.
It found a range of unlawful discharges, including milk vat waste and large volumes of diary effluent, being discharged directly into farm drains which flow into the Waihou River.
It said improvements should have been made on the farm years ago and the court order did put the farm in a difficult situation with calving underway.
The council's Patrick Lynch said a robust effluent management system is now in place.