Environmental consultant who led the development of the Manawatu-Whanganui regional plan says the Environmental Court's rulings on appeals against the disputed plan is a victory for sound science.
The court's decisions mean all intensive farming and horticulture operations, including dairying, irrigated sheep and beef and cropping farms and market gardens, will be required by regulation to have nutrient management plans to reduce their impact on waterways.
There are also more stringent rules on hill country erosion control and protecting biodiversity.
Greg Carlyon, now in an independent environmental practice after leaving the council last year, is pleased the Environment Court has restored some elements in the original One Plan that had been watered down during the consultancy and submission process.
Mr Carlyon says farmers should stopping worrying about the issue of having to comply with regulations and think about how working to a farm management plan would benefit them and protect the environment that has reached a very degraded state in some areas.
"The system that we designed means that they need to think about what they're doing before they do it.
"The science that supported that said things like 'if you use your effluent from your dairy farm wisely it could save you $30,000 a year in fertiliser costs."