River water quality Data - Page 2

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.

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.

23 April 2021: A new version of this data set has been published. It includes data on 4 parameters (Ammoniacal nitrogen (adjusted), Escherichia coli, Macroinvertebrate Community Index and Total Phosphorus) that had been missing from the file that was published as part of the Our freshwater 2020 release in April 16 2020. The updated data set also includes data on DRP for all 593,337 REC segments, since the file from April 16 2020 only had data for 255,860 of these segments.

16 April 2020: Subsequent to publication in April 2019 we discovered two small errors with this dataset. These included:

• Errors in the coordinates of some sites and their associated metadata (such as landcover and elevation).
• Errors in our calculation of dominant landcover.

In addition, flow data from TopNet has also been updated.

These changes have a minor impact on overall results. These changes have have been corrected, and are republished here, as part of the Our freshwater 2020 release.

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IMPORTANT INFORMATION

1) The main (cleaned) dataset is structured by each row having a nzsegment and np_id combination. A large dataset (~ 1 GB) has resulted, due to the inclusion of the ANZG/NOF columns and the 10 different np_id values. There are ~ 6 million rows to this dataset, however a 32-bit version of Microsoft Excel will only display/download ~ 1 million rows. __A DBMS, statistical or GIS application is needed to view the entire dataset__.

2) A smaller raw dataset (see attachments) is provided which structures each row relating to a river segment and drops the ANZG/NOF columns.

3) The attached metadata/date quality report provides further information on the NOF, ANZG and the "McDowell meet/doesnt meet" attachment.

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This dataset contains ten parameters of water quality based on measurements made at monitored river sites:

• Nitrate-nitrogen
• Ammoniacal nitrogen
• Ammoniacal nitrogen (adjusted)
• Total nitrogen
• Total phosphorus
• Dissolved reactive phosphorus
• Water clarity
• Turbidity
• Escherichia coli
• Macroinvertebrate community index These parameters are used to measure:
• Modelled median values for all of New Zealand’s river length for the period 2013 to 2017
• For selected indicators, how the modelled values compare to the National Objectives Framework (NOF) (MfE, 2017) bands related to ecosystem health and human health for recreation, and to expected concentrations in natural conditions, as shown by the default guideline values in the Australian and New Zealand guidelines for fresh and marine water quality (ANZG, 2018)

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 www.mfe.govt.nz/publications/fresh-water/spatial-m...

Heavy metals in river waters are an indicator of river water quality. We monitor a subset of rivers and streams in predominantly urban areas in Auckland, Wellington, and Christchurch, and look at how these values are changing over time. This indicator shows:

• trends in concentrations based on measurements made at monitoring sites during the seven-year period from 2011 to 2017

Summary report available at www.mfe.govt.nz/publications/fresh-water/urban-riv....

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.

Heavy metals in river waters are an indicator of river water quality. We monitor a subset of rivers and streams in predominantly urban areas in Auckland, Wellington, and Christchurch, and look at how these values are changing over time. This indicator shows:

• concentrations of dissolved copper and zinc measured at monitoring sites for the three-year period from 2015 to 2017
• how these compare to the default guideline values for the protection of 95 percent of species in the Australian and New Zealand guidelines for fresh and marine water quality (ANZG, 2018)

Summary report available at www.mfe.govt.nz/publications/fresh-water/urban-riv....

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.

These data are the raw river water quality observations used to calculate state and trends for the period ending 2017.

It contains ten parameters of water quality based on measurements made at monitored river sites:

• Nitrate-nitrogen
• Ammoniacal nitrogen
• Ammoniacal nitrogen (adjusted)
• Total nitrogen
• Total phosphorus
• Dissolved reactive phosphorus
• Water clarity
• Turbidity
• Escherichia coli
• Macroinvertebrate community index

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More information on this dataset and how it relates to our environmental reporting indicators and topics can be found in the summary report available at www.mfe.govt.nz/publications/fresh-water/water-qua....

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Note: This dataset has a large number of rows, which Microsoft Excel may not be able to fully open. A DBMS, statistical or GIS application is needed to view the entire dataset.

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: Escherichia coli" indicator (available at www.stats.govt.nz/indicators/river-water-quality-e...).

This dataset contains one parameter of water quality based on measurements made at monitored river sites:

• Escherichia coli

Escherichia coli 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.

This dataset includes:

• E. coli concentrations measured at monitoring sites for New Zealand’s river length for the period 2016–2020
• A comparison of measured E. coli concentrations at monitored sites with the proportion of human modified landcover in the upstream catchment area
• predicted risk of Campylobacter infection, as shown by the median concentration, 95th percentile and percentage of results above 260 and 540 colony forming units per 100 millilitres (cfu/100 mL) compared to the National Objectives Framework (NOF) bands related to human contact

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:

• MCI scores as measured median values at monitored sites for the period 2016–2020
• how these compare to the macroinvertebrates National Objectives Framework (NOF) bands related to ecosystem health.

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....