"It means we can understand the science at catchment scale," says Burger. "Through modelling and monitoring, we can relate the actions of every single farm plan to collective and demonstrable outcomes downstream."
Over the next two years all landowners will have farm management and improvement plans, with the longer-term goal of enhancing the mana and resilience of the catchment for future generations.
"First individual farmers need to understand their own situation when it comes to water quality – and what options they have to reduce environmental risk," says Burger. "Then it will be a matter of implementing actions across the catchment and monitoring the change."
Robust science is a key ingredient of DairyNZ's drive towards improving water quality, Burger says: "For example, in terms of the science being employed to mitigate contaminant run-off from farms, we are trying to understand the relationship between the contaminant load upstream and downstream values.
"We need to have a high level of certainty we are focusing on the right area [of cause and effect]. It is not an easy task because the way in which contaminants flow and change between the source and the receiving environment varies within and across catchments.
There are all sorts of processes going on and some may not be observed for decades."
That said, DairyNZ's scientific exploration of the complex subject of water quality is designed to identify best practice interventions that can be applied as quickly as possible, he says.
One example is seepage wetlands – which DairyNZ work has shown can remove up to 75 per cent of nitrate from runoff through bacteria and uptake by plants, vastly improving water quality. Wetlands also trap sediment and phosphorus and reduce faecal bacteria and help protect land from flood damage by slowing or holding surface water and releasing it slowly over time. They are also a valuable home for native plants and animals
Burger says Burger says scientific work is also being carried out to support the following improvements:
•Edge of field mitigation – tools like wood chip bio-reactors, constructed wetlands and detainment bunds are placed on the "edge of field" to improve the quality of the water before it enters waterways via farms. DairyNZ is working with NIWA and other agencies to understand how effective these tools are and how to optimise their design to ultimately support greater uptake by farmers nationwide.
•Farm environmental plans – more than 2000 farms (out of 12,000 total dairy farms in New Zealand ) already have a Sustaibnable Milk Farm Environment Plan like those being proposed in the ACE project. Burger says the sector is aiming for all farms to have a farm plan by 2025.
•Good Farming Practices – DairyNZ co-launched the Good Farming Practice (GFP) Water Quality Action Plan alongside primary industry partners, regional councils and the Ministry for the Environment last year. This plan has already developed a national set of GFP principles and is now working towards implementing them over the next few years.
•Riparian planning tool – DairyNZ's Riparian Planner helps farmers set up a plan and advises on suitable species to plant and how this work should be carried out. It won an award by the New Zealand Association of Resource Management for Outstanding Contribution in 2016 and more than 2200 dairy farmers have used this tool.
•Effluent management – farmers have improved effluent infrastructure and practices across many regions. "Ten years ago, non-compliance rates were 17-18 per cent in some regions; that is now down to about five per cent or less," says Burger.
•Increased environmental spend by farmers – the 2015 DairyNZ and Federated Farmers survey showed an estimated environmental spend by farmers of over $1 billion from 2010 to 2015, equating to $18,000 a year per farm, or $90,000 over the five-year period – with 70 per cent of that spending estimated to have been in the area of effluent management. Burger says the other 30 per cent has largely been spent on wetlands protection or providing new wetlands on farms, plus riparian fencing and planting: "Those plants cost farmers quite a bit of money and maintenance is quite high too."
•The Sustainable Dairy Water Accord launched in 2013 has seen 97 per cent of significant waterways on dairy farms (covering 26,000kms) fenced off to keep cows out; 99.7 per cent of regular stock crossings now have bridges or culverts to achieve the same aim.
Those figures have been criticised by some commentators, saying they do not cover smaller streams flowing into larger streams but Burger says: "We started this programme many years ago as a nationwide, voluntary initiative because we wanted the sector to get on that journey – covering waterways wider than a metre and deeper than a gumboot.
"There is no quick fix. No one can do it all overnight. But what's been achieved so far, well before regulation, needs to be celebrated even as we acknowledge there is more that needs to be done."
