Study Shows Dairy Farm Work is Helping Improve Water Quality

The implementation of Good Management Practices on-farm does improve water quality, proves new research that analysed water quality trends over 20 years.

As part of an Our Land and Water study to analyse historical data, DairyNZ’s environmental science team, in collaboration with AgResearch and Lincoln University, has revisited dairy farms in five catchments to assess whether on-farm actions have helped improve water quality over time.

The five catchments – Waiokura (South Taranaki), Toenepi (Waikato), Waikakahi (Canterbury), Bog Burn (Southland) and Inchbonnie (West Coast) – are dairy farming areas that were part of the 2001–2010 Best Practice Dairy Catchments project, which monitored water quality and environmental work on-farm.

Researchers found that, over the 20-year monitoring period, 67 percent of in-stream water quality trends across the five catchments were improving, and the levels of most contaminants in water have decreased due to farmers implementing good management practices (GMPs) such as improved effluent management and stock exclusion.