An assessment of the benefits of cleaner streams: A New Zealand case study

Abstract

Water pollution is now considered to be one of the most important environmental issues facing New Zealand. Water quality in rivers, lakes and streams is generally falling alongside the increase in farming intensity, especially in dairying. Currently, technical and regulatory mechanisms to reduce non-point source pollution from agriculture are the focus of an intensive effort involving industry, researchers, regulators and other stakeholders. The research described in this non-technical paper aims to complement existing knowledge by developing appropriate methodology for valuing water quality improvements in New Zealand. It is envisaged that this type of information will assist the policy process by allowing decision makers to consider both the costs and the benefits of different levels of water quality improvements. This research is based on a case study of the Karapiro catchment in the North Island of New Zealand. It uses choice analysis to assess people’s preferences and willingness to pay for different levels of water quality improvement in catchment streams. Choice analysis methods ask respondents to choose between one group of environmental services or characteristics, at a given price or cost to the individual, and another group of environmental characteristics at a different price or cost. Each respondent is usually asked to repeat this exercise several times. The results from this study indicate that respondents would be willing to pay for cleaner water for swimming, for better ecological health (with eels, bullies and smelt present), for the presence of trout and for better clarity such that ‘you can usually see the bottom’. Respondent preferences were strongest for water suitable for swimming, followed by ecological health, presence of trout and clarity.