While the number of incidents was much improved, the year did include one of the worst cases of its kind – so bad, the Waikato Regional Council labelled it an “environmental disaster”.

That was the case of Kenneth McIntyre and Cassandra Kidd and involved the repeated polluting of the Piako River near Morrinsville.

The pair had a contract with Open Country Dairy Ltd to dispose of up to 13 truck and trailer loads of dairy manufacturing by-product on their farm a day.

Effluent from their farm entered waterways and was likely to have resulted in nitrate and pathogenic organisms entering groundwater, authorities found.

McIntyre, who had a history of similar offending, was sentenced to five months’ home detention and fined $100,000. Kidd was convicted and discharged.

Federated Farmers dairy chairperson Richard McIntyre said there were various factors that explained the latest year’s improved figures.

On the back several profitable seasons in a row, many farmers had invested in effluent infrastructure upgrades. Technology was also improving, he said.

“I think also there’s a greater element now of farmers policing their own and urging colleagues to make improvements. They’re not prepared to let the actions of their neighbours reflect badly on them or their industry.

“But we’re only human and very occasionally mistakes are made and incidents on farm cause unwanted effluent issues, despite the best efforts of farmers and their staff.”

Forest and Bird freshwater advocate Tom Kay said the figures were a promising sign.

“It’s hard to compare over time given rules or council monitoring efforts might have changed, but I hope this reflects a genuine improvement in the management of dairy farm effluent and means fewer streams and rivers are being polluted,” he said.

“However, considering the rhetoric from industry on everything it’s supposedly doing to drive more sustainable farming in Aotearoa, it’s a shame the numbers aren’t lower”.

Kay said rules needed to tighten in order to keep rivers healthy in coming years. It was critical councils were adequately funded to fulfil their compliance, monitoring and enforcement responsibilities, he said.

“We’ve still got a lot to do, but maybe this is a sign we’re heading in the right direction.”

Ecologist and sustainable agricultural adviser Alison Dewes said more could be done around the messaging and management of permitted and consented activities.

“At the moment there’s still ducking and diving between responsible agencies and it’s no wonder some farmers feel rightfully confused by who is in charge of what resource. This is a big issue,” she said.

Dairy effluent offending, 2021/2022:

• Kenneth McIntyre, $100,000 and five months’ home detention. Nine charges of discharging contaminants into the environment, three of breaching court orders imposed in previous prosecutions and one charge of excavating a stream. Cassandra Kidd convicted and discharged on two related charges. Waikato Regional Council.
• Stephen Povey, $56,000. Two charges of discharging dairy effluent to land where it may enter water. Waikato Regional Council.
• Badham Dairies Ltd, $26,000. One charge of discharging dairy effluent to land where it may enter water. Prosecuted by Environment Canterbury.