Finding out about our water quality
Detailed reports on river water quality in New Zealand, aimed at helping improve the management of our waterways are now
available.
The reports titled “Spatial patterns in state and trends of environmental quality in New Zealand rivers” and “Nationwide
and regional state and trends in river water quality” were produced by National Institute for Water and Atmospheric
Research (NIWA).
“The Ministry commissioned the reports as we had little or no information of this kind on a national scale. Results from
over 700 rivers and streams were analysed to produce an overview of water quality across the whole country.” Barry
Carbon, Chief Executive for the Ministry for the Environment said.
The recently developed River Environment Classification (REC) system was used to look at the effect of factors like
climate and land use on river water quality.
The reports found that:
water quality (as defined by nutrients, the bacterium E.coli, and clarity) is consistently poorer in rivers in
pasture-dominated, mainly lowland, catchments than in rivers in predominantly natural catchments like native bush
urban waterways have the poorest water quality of all rivers
interpretation of observed trends in water quality is complicated by the links with climate variability. This means that
longer term monitoring records are required to determine the significance and cause of water quality trends with more
certainty.
The river water quality studies have been used to inform the government’s Sustainable Development Water Programme of
Action. This programme is looking at improving the way we manage freshwater use and quality and is exploring the
opportunities for identifying water bodies of national interest.
View the reports on the Ministry for the Environment website: www.mfe.govt.nz