"Data collected at two of the four farms showed that they also managed to cut the effluent volume generated by roughly half."
The dairy industry continued to spend many millions of dollars on projects aimed at mitigating adverse environmental effects and improving its image, and the trials proved that with a few simple, cost-effective changes, it was possible to tackle issues related to water extraction and point source effluent management.
"This not only improves environmental performance, but can result in significant reduction in on-farm operating costs," he said.
Central to the trials had been the use of water meters to measure actual use at different points around the dairy, installation of more water-efficient cleaning nozzles, and diverting as much clean stormwater as practicable away from the treatment ponds.
Other initiatives on some farms included changing from water to electric-driven yard backing gates, and using recycled effluent to clean their dairy yards.
Ken Finlayson, who milks 780 Friesians on 300ha at Ngararatunua, said since moving into a new dairy shed three years ago he had almost halved his water use, largely though changing nozzles on hoses, the farm dairy bridge and D-gate, by capturing plant wash water and recycling through a yard wash system.
"We're saving about 5.4 million litres of water per dairy season, which equates to usage of about 27 litres per cow per day on average," he said. Typical standard industry usage is about 70 litres per cow per day.
Apart from the obvious environmental benefits — it was much easier to be compliant without handling such large volumes of effluent — the fact that he would not need to pay for an additional effluent storage pond had saved him about $80,000.
Mr Wright said the the idea for the effluent reduction project stemmed from his own frustration that co-operative and willing Northland farmers could still find it difficult to comply with their resource consent conditions.
