This report is one of two prepared for the Ministry for the Environment by NIWA, which update national indicator data for river water quality in New Zealand and help provide the evidence base for policy and decision makers.
This report is one of two prepared for the Ministry for the Environment by NIWA, which update national indicator data for river water quality in New Zealand and help provide the evidence base for policy and decision makers.
This report provides information on the state of New Zealand’s rivers and recent trends in river water quality. The report includes data from about 600 regional council and National River Water Quality Network sites. This report updates an earlier report based on the national network only for the 19 year period, 1989 to 2007.
The December 2010 version of the report replaces an earlier version published in May 2010. The key difference is that the latest version provides more detailed commentary on the methodology used, specifically giving a more comprehensive assessment of the uncertainties that arise from the estimation of flows.
The second report models water quality for all river reaches in New Zealand using water quality data for the 600 regional council and national network sites and a range of catchment features such as climate, geology, topography and land cover.