Valuation of agricultural impacts on rivers and streams using choice modelling: a New Zealand case study

Increasing substitution of dry land pastoral and arable farming for water-intensive practices is placing pressure on water resources in Canterbury. Although there is a large body of scientific data documenting environmental change, there is a general lack of information on the economic values of agricultural impacts on rivers and streams. This paper applies an economic non-market valuation method to help address this issue. Three impacts are considered: health risks of pathogens from animal waste; ecological effects of excess nutrients; and low-flow impacts of irrigation. This study provides a valuation of outcomes for public agri-environmental policy implemented in Canterbury such as The Dairy and Clean Streams Accord, Living Streams and The Restorative Programme for Lowland Streams. Modelling results indicate that the 5-year economic value for improvements to rivers and streams in Canterbury provided by agri-environmental policy is estimated to be about $186 million