There is now evidence that the money and energy invested by farmers and the wider community in water quality improvement projects in the Manawatu-Rangitikei region are making a difference, with rivers more swimmable.
Federated Farmers Manawatū-Rangitikei President Richard Morrison, while welcoming the findings of an independent report commissioned by Horizons Regional Council and the Ministry for the Environment, said it was time to spend money on projects to clean up waterways rather than on legal action.
"Now we have independent confirmation of the effectiveness of One Plan's approach and how working together on targeted, prioritised, science-informed projects are getting the water quality indicators moving in the right direction across the region," he said.
"Let's spend our money and time on those, not legal action and inflexible regulations".
The study, conducted by LWP and reviewed by Niwa and StatsNZ, showed strong statistical evidence of reductions in sediment (suspended sediment, water clarity and turbidity), as well as E.coli, in local waterways.
The report's leader author, Dr Ton Snelder, said modelling showed there has been a 5 to 8 per cent improvement in "swimmability" in the region in the decade ending in 2016.
Mr Morrison said it was notable the improvements had been driven not so much by regulation, but from the council working side by side with farmers and others on practical solutions, tailored to each catchment and informed by science.
"We also point out that the gains have come at a time when the council was pursuing the course it had set itself under One Plan, and prior to it all being thrown into uncertainty by the Environmental Defence Society and Fish & Game legal challenge," he said.
The report has shown water quality for sediment and E.coli have improved over the past seven to 10 years in the Horizons region, which includes Tararua, with signs interventions are contributing to these water quality improvements.
Horizons Regional Council natural resources and partnership group manager Dr Jon Roygard said the case study demonstrated how regulatory and non-regulatory intervention, including farm plans, targeting action on highly erodible land, upgrading point source discharges and undertaking fencing and planting of stream margins could effectively improve water quality.
"Further fencing and planting has also been completed through Freshwater Grants and a Clean Up Fund project through the Manawatu River Leaders' Forum," he said.
"To date 683 whole farm plans, covering more than 500,000ha, has included advising on 'best' farm practice and the planting of 14 million trees and more than 570,000m of waterways being fenced."
But, Mr Morrison said farmers - as much as anyone else - realised there was a long way to go before they could say they were on top of waterway problems.