Freshwater Management: State of water quality and options for management in the Waipahi Catchment

The main pressures on water quality are as a consequence of land-based activities. Agriculture is the world’s greatest contributor of non-point source pollution, which needs to be managed. The current international approach to freshwater management is Integrated Catchment Management. In New Zealand agriculture is the dominant land use and intensity has increased, which has had subsequent impacts on freshwater. New Zealand’s legislation of the Resource Management Act (1991) and National Policy Statement for Freshwater Management (2014) provides a planning framework with statutory basis for Integrated Catchment Management. This research involved a case study of the Waipahi catchment to identify what impact agriculture has had on water quality spatially and temporally, and explore issues and options for future management. The research involved a mixed methods approach of conducting water quality sampling and key informant interviews of stakeholders involved in freshwater management of the Waipahi catchment. Results showed water quality in Waipahi catchment could be improved for nitrate nitrite nitrogen, phosphate and Escherichia. Consequently, best management practices should be implemented to improve freshwater quality. If future monitoring does not show improvements, there will have to be changes in land use from agriculture to the next best use. Results also showed a lack of deliberate and strategic planning for the management of the Waipahi catchment. Although there is statutory basis for the integration of the physical environment, there is a lack statutory basis for social aspects. Intervention at the planning level to include statutory basis for social aspects would provide an opportunity to further implement Integrated Catchment Management in the Waipahi catchment