Golden Bay marine farmers are crying foul over a spate of dairy effluent discharges down the Aorere River which they say are endangering their multimillion-dollar businesses.

High bacterial readings have been recorded on mussel farms off the coast from Collingwood in recent months, with marine farmers saying they were almost at a level where the area would have been forced to close had they been harvesting at the time.

They say further problems had only been avoided because strong wind had blown plumes of pollution away from their farms.

Testing had revealed it came from cows and they had photographic evidence of sloppy dairying practices which they believe had contributed. These included cows using streams for crossings, unfenced waterways and poor effluent storage and disposal.

The marine farmers have complained to the Tasman District Council, saying it needs to tighten up weak rules and increase monitoring.

The issue is not only an embarrassment for the council - which has since held talks with all the parties - but also for Aorere Valley dairy farmers who have been lauded for their efforts to clean up the river catchment since 2005 when pollution got so bad marine farms could only harvest 28 per cent of the time.

The farmer-led Aorere catchment group has been held up as a model for voluntary action and has attracted international attention, including a visit from an Organisation for Economic Co-operation and Development representative in August.

Marine farmers are wary of speaking out publicly, for fear of spooking their customers and upsetting locals, but Westhaven Shellfish owner Alistair McDonald said he was worried that if there were too many high E. coli readings it might prevent him harvesting clams off the beach for his live supermarket trade.

He had seen large amounts of pollution coming down the river even when it was low and the weather had been fine. "I got a high bug count the next day."

Fonterra and the council were paying only "lip service" with their "softly, softly" approach to the problem, he said. Their rules were "wishy washy", still allowed treated effluent to be directly discharged into waterways and had failed to keep up with the intensification of dairy farming, which had seen farms grow to as many as 1500 cows in the valley.

"We have been trying to get extra space for mussel farming but there is no point if you have cow farmers plonking dung down the river."

In a carefully worded statement, Wayne MacDonald, chairman of the Marlborough Shellfish Quality Programme (MSQP), which monitors growing areas in the top of the south, confirmed there had been a spike in bacterial levels, which if had remained high would have meant the Collingwood area would have been closed to harvesting by the Primary Industries Ministry.

Further testing showed it came from a bovine source.

While MSQP acknowledged the efforts by most dairy farmers in the Aorere to manage their effluent, the agency wanted real time monitoring of the river, he said. It wanted to work with the council on solutions and believed best practice methods could be adopted, Mr MacDonald said.

Nelson MP Nick Smith said he had met the marine farmers over their concerns and the recent spikes in pollution were a "real wake-up call".

It showed the council and the farming community needed to do more to reduce the impact of both bacteria and sediment pollution in the bay's waterways.

"The issue is just not about the impacts on harvesting for farmed shellfish but is also a concern in terms of Golden Bay's hugely important visitor industry."

Federated Farmers Golden Bay dairy spokesman Sue Brown said farmers were shocked to hear of the recent spikes, which she understood were the first for five years.

Fonterra and the council had been unable to identify any on-farm accident or effluent system failure as the source and it was likely bad weather had played a significant part, she said.

"It's unclear what is going on and it's frustrating for all involved," she said.

TDC environment and planning committee chairman Stuart Bryant questioned the marine farmers' evidence, saying he was yet to be convinced that dairying was the sole cause or that it was a major problem.

Farmers were doing their best to minimise effluent getting into waterways, with some spending more than $100,000 on weeping walls and storage systems, he said.

The council's environmental information manager, Rob Smith, confirmed it had received four complaints over the last six months but its investigations had not identified "anything we can jump in and fix".

In one case the source of the dairy discharge had been traced to an infrequently used stock crossing which was permitted under the council's rules, while it hadn't been able to find what had caused two other incidents, he said. In the fourth case grazing of a road verge was to blame.

The council's own monitoring of the Aorere - which had been increased from quarterly to monthly - hadn't shown up anything unusual, Mr Smith said. It had measured only four E. coli spikes above alert levels over the last two years and each followed heavy rain.

He defended its dairying and effluent management rules, saying they were no more permissive than a number of other councils and broadly in line with industry standards.

The council was about to review its water management regime as required by the Government, Mr Smith said. "We are always interested in improving our performance but generally water quality in our district is pretty good."

- © Fairfax NZ News

Comments