New Zealand's Environment Reporting Series: The Ministry for the Environment and StatsNZ
Urban water quality indicators include heavy metals, nutrients, and E.coli. The concentrations of these indicators are compared to the proportion of urban land cover in catchments.
Heavy metals have the ability to accumulate in sediments, shellfish, and other aquatic organisms. Metals can reach toxic levels in organisms making them unsafe to consume and can be toxic to aquatic life. Nutrients can cause excessive algal growth and E.coli has the ability to make people sick while they are swimming if concentrations are high enough. Rivers with poor water quality are rarely suitable for recreation and provide poor habitats for aquatic species.
File contains data analysis of medians and percentiles by site for water quality indicators, and includes the proportion of urban land cover in catchments in Auckland, Wellington and Christchurch over the period 2013–2015.
Auckland Council, Greater Wellington Regional Council, and Christchurch City Council