River water quality Data

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.

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 related to each sampling occasion by site for each water quality indicator in Auckland, Wellington, and Christchurch over the period 1985–15.

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.

Zinc and copper are heavy metals that can accumulate in sediments, shellfish, and other aquatic organisms. Metals can reach toxic levels in organisms making them unsafe to eat and can be toxic to aquatic life. Nitrogen and phosphorus are nutrients that can cause excessive algal growth. Ammonical nitrogen and nitrate-nitrogen can be toxic to aquatic life if concentrations in streams are high enough. E.coli is an indicator of disease-causing organisms, which may affect human health and recreational values in streams.

File contains trend analyses by site for water quality indicators in Auckland, Wellington, and Christchurch over the period 2008–15.

Adapted by Ministry for the Environment and Statistics New Zealand to provide for environmental reporting transparency. Dataset used to develop the "River water quality: phosphorus" indicator (available at www.stats.govt.nz/indicators/river-water-quality-p...).

Phosphorus in river waters is one of five parameters that provide an overview of New Zealand’s river water quality and how it is changing over time. Phosphorus is an essential nutrient for plants and is a natural component of healthy rivers. Agricultural and urban land use, and infrastructure such as wastewater treatments plants, can add more phosphorus to waterways, which can increase algae growth and biomass. This in turn causes deterioration of river habitats.

This dataset includes:

• trends in concentrations of total phosphorus and dissolved reactive phosphorus based on measurements made at monitoring sites during the 10-year period from 2011 to 2020, the 20-year period from 2001 to 2020, and the 30-year period from 1991 to 2020.

More information on this dataset and how it relates to our environmental reporting indicators and topics can be found in the attached data quality pdf. Summary report available at environment.govt.nz/publications/environment-aotea....

Adapted by Ministry for the Environment and Statistics New Zealand to provide for environmental reporting transparency. Dataset used to develop the "River water quality: phosphorus" indicator (available at www.stats.govt.nz/indicators/river-water-quality-p...).

Phosphorus in river waters is one of five parameters that provide an overview of New Zealand’s river water quality and how it is changing over time. Phosphorus is an essential nutrient for plants and is a natural component of healthy rivers. Agricultural and urban land use, and infrastructure such as wastewater treatments plants, can add more phosphorus to waterways, which can increase algae growth and biomass. This in turn causes deterioration of river habitats.

This dataset includes:

• concentrations of total phosphorus (TP) and dissolved reactive phosphorus (DRP) measured at monitored sites, expressed as percentiles for the period of 2016–2020
• a comparison of measured total phosphorus and dissolved reactive phosphorus concentrations at monitored sites with the proportion of human modified landcover in the upstream catchment area
• how measured median total phosphorus and dissolved reactive phosphorus concentrations compare to the default guideline values in the Australian and New Zealand guidelines for fresh and marine water quality (ANZG, 2018), which indicates the risk of environmental impairment
• measured dissolved reactive phosphorus concentrations compared to the National Objectives Framework (NOF) bands related to ecosystem health (MfE, 2020)

More information on this dataset and how it relates to our environmental reporting indicators and topics can be found in the attached data quality pdf. Summary report available at environment.govt.nz/publications/environment-aotea....

About

Adapted by Ministry for the Environment and Statistics New Zealand to provide for environmental reporting transparency. Dataset used to develop the "River water quality: phosphorus" indicator (available at www.stats.govt.nz/indicators/river-water-quality-p...).

Phosphorus in river waters is one of five parameters that provide an overview of New Zealand’s river water quality and how it is changing over time. Phosphorus is an essential nutrient for plants and is a natural component of healthy rivers. Agricultural and urban land use, and infrastructure such as wastewater treatments plants, can add more phosphorus to waterways, which can increase algae growth and biomass. This in turn causes deterioration of river habitats.

This dataset includes:

• trends in concentrations of total phosphorus and dissolved reactive phosphorus based on measurements made at monitoring sites during the 10-year period from 2011 to 2020, the 20-year period from 2001 to 2020, and the 30-year period from 1991 to 2020.

More information on this dataset and how it relates to our environmental reporting indicators and topics can be found in the attached data quality pdf. Summary report available at environment.govt.nz/publications/environment-aotea....

Adapted by Ministry for the Environment and Statistics New Zealand to provide for environmental reporting transparency. Dataset used to develop the “River water quality: Nitrogen” indicator, (available at www.stats.govt.nz/indicators/river-water-quality-n...).

Nitrogen in river waters is one of five parameters that provide an overview of New Zealand’s River water quality and how it is changing over time. Nitrogen is an essential nutrient for plants and algae. Some nutrient supply is a natural component of healthy rivers, but agricultural and urban land use, and infrastructure such as wastewater treatment plants, can add more nitrogen to waterways. Too much nitrogen can lead to excessive growth of algae, which can deteriorate river habitats. In very high concentrations, some forms of nitrogen, including nitrate-nitrogen and ammoniacal nitrogen, can be toxic to aquatic life.

This dataset shows:

• trends in concentrations of total nitrogen, nitrate-nitrite-nitrogen, and ammoniacal nitrogen based on measurements made at monitoring sites during the 10-year period from 2011 to 2020, the 20-year period from 2001 to 2020, and the 30-year period from 1991 to 2020.

More information on this dataset and how it relates to our environmental reporting indicators and topics can be found in the attached data quality pdf.

Summary report available at environment.govt.nz/publications/environment-aotea....

Adapted by Ministry for the Environment and Statistics New Zealand to provide for environmental reporting transparency. Dataset used to develop the “River water quality: Nitrogen” indicator, (available at www.stats.govt.nz/indicators/river-water-quality-n...).

Nitrogen in river waters is one of five parameters that provide an overview of New Zealand’s River water quality and how it is changing over time. Nitrogen is an essential nutrient for plants and algae. Some nutrient supply is a natural component of healthy rivers, but agricultural and urban land use, and infrastructure such as wastewater treatment plants, can add more nitrogen to waterways. Too much nitrogen can lead to excessive growth of algae, which can deteriorate river habitats. In very high concentrations, some forms of nitrogen, including nitrate-nitrogen and ammoniacal nitrogen, can be toxic to aquatic life.

This dataset shows:

• concentrations of total nitrogen (TN), nitrate-nitrite-nitrogen (NNN) and ammoniacal nitrogen (NH4N) measured at monitored sites, expressed as percentiles for the period 2016–2020
• a comparison of measured nitrate-nitrite-nitrogen and ammoniacal nitrogen concentrations at monitored sites with the proportion of human modified landcover in the upstream catchment area
• how measured median values compare to the default guideline values in the Australian and New Zealand guidelines for fresh and marine water quality (ANZG, 2018), which indicates the risk of environmental impairment
• toxicity to aquatic species, as defined by the National Objectives Framework (NOF) bands related to ecosystem health (MfE, 2020)

More information on this dataset and how it relates to our environmental reporting indicators and topics can be found in the attached data quality pdf.

Summary report available at environment.govt.nz/publications/environment-aotea....

Adapted by Ministry for the Environment and Statistics New Zealand to provide for environmental reporting transparency. Dataset used to develop the “River water quality: Nitrogen” indicator, (available at www.stats.govt.nz/indicators/river-water-quality-n...).

Nitrogen in river waters is one of five parameters that provide an overview of New Zealand’s river water quality and how it is changing over time. Nitrogen is an essential nutrient for plants and algae. Some nutrient supply is a natural component of healthy rivers, but agricultural and urban land use, and infrastructure such as wastewater treatment plants, can add more nitrogen to waterways. Too much nitrogen can lead to excessive growth of algae, which can deteriorate river habitats. In very high concentrations, some forms of nitrogen, including nitrate-nitrogen and ammoniacal nitrogen, can be toxic to aquatic life.

This dataset shows:

• trends in concentrations of total nitrogen, nitrate-nitrite-nitrogen, and ammoniacal nitrogen based on measurements made at monitoring sites during the 10-year period from 2011 to 2020, the 20-year period from 2001 to 2020, and the 30-year period from 1991 to 2020.

More information on this dataset and how it relates to our environmental reporting indicators and topics can be found in the attached data quality pdf.

Summary report available at environment.govt.nz/publications/environment-aotea....

Adapted by Ministry for the Environment and Statistics New Zealand to provide for environmental reporting transparency. Dataset used to develop the "River water quality: macroinvertebrate community index" indicator (available at www.stats.govt.nz/indicators/river-water-quality-m...).

Benthic macroinvertebrates are small animals without backbones (for example, insects and worms). They live on and under submerged logs, rocks, and aquatic plants on the beds of rivers and streams during some part of their life cycle. Macroinvertebrates play a central role in stream ecosystems by feeding on periphyton (algae), macrophytes (aquatic plants), dead leaves and wood, or on each other. In turn, they are an important food source for fish and birds.

The macroinvertebrate community index (MCI) is used as an indicator of water quality and overall stream health. It is one of five parameters that provide an overview of New Zealand’s River water quality and how it is changing over time. This data shows

• trends in median MCI scores for the 10-year period from 2011 to 2020, the 20-year period from 2001 to 2020, and the 30-year period from 1991 to 2020.

More information on this dataset and how it relates to our environmental reporting indicators and topics can be found in the attached data quality pdf. Summary report available at environment.govt.nz/publications/environment-aotea....