River water quality Data

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.

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.

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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This dataset measures how water quality in New Zealand’s rivers is changing over time. It contains nine parameters of water quality based on measurements made at monitored river sites in years 1990-2017:

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

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/water-qua....

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.

​

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...

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.

​

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

This dataset includes:

• Median values for the period 2013 to 2017
• for selected indicators, how these 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/water-qua....

River water quality is valued for many reasons including ecological function and habitat, recreational value, its role in supporting people and industry, and its cultural significance. Nutrients such as nitrogen and phosphorus are essential for plant growth, however too much in rivers can lead to excessive growth of river algae, which can degrade habitat.

High concentrations of nitrogen in the form of ammoniacal nitrogen and nitrate-nitrogen can be toxic to fish and other aquatic animals, and nitrate-nitrogen can be toxic to humans. Water clarity is a measure of underwater visibility, and affects habitat of aquatic life such as fish and birds, and can also impact on aesthetic values and recreational use of rivers and streams. Escherichia coli (E.coli) can indicate the presence of pathogens (disease-causing organisms) from animal or human faeces, which can cause illness.

File contains the model outputs for river water quality indicators as medians for each river segment in New Zealand’s digital river network.

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.

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.

River water quality water is valued for many reasons including ecological function and habitat, recreational value, its role in supporting people and industry, and its cultural significance. Nutrients such as nitrogen and phosphorus are essential for plant growth, however too much in rivers can lead to ‘nuisance’ growths of river algae and aquatic plants, degrading habitat. High concentrations in the form of ammoniacal nitrogen and nitrate-nitrogen can be toxic to fish and other aquatic animals. Water clarity is a measure of underwater visibility, and affects habitat of aquatic life such as fish and birds, and can also impact on aesthetic values and recreational use of rivers and streams. Escherichia coli (E.coli) can indicate the presence of pathogens (disease-causing organisms) from animal or human faeces, which can cause illness.

File contains raw data collected at regional council and NIWA monitored sites over the period 1975-2013. Fields are described as follows. Refer to Larned et al. 2015 for further details:
* nemarid ---- Unique NIWA ID
* lawaid ---- Unique LAWA ID
* rcid ---- Collection agency
* srcid ---- Region site is located in
* sflag ---- River (r) or Estuary (e)
* river ---- River name
* location ---- Name of site, assigned by collection agency
* nzmge ---- easting
* nzmgn ---- northing
* nzreach ---- REC1 segment identifier
* sdate ---- Sample date (yyyy-mm-dd)
* Q ---- Flow recorded when sample was taken (if available), cumecs
* npid ---- NIWA parameter ID (as used in Larned et al. 2015)
* lpid ---- LAWA parameter ID
* fdval ---- Parameter value (units are mg/m3, except CLAR (m) and ECOLI (n/100 mL))

For more information please see:
Larned, S, Snelder, T, Unwin, M, McBride, G, Verburg, P, McMillan, H (2015).Analysis of Water Quality in New Zealand lakes and Rivers: data sources, data sets, assumptions, limitations, methods and results. NIWA Client Report no. CHC2015-033. Available at data.mfe.govt.nz/x/Mo8VUY from the Ministry for the Environment dataservice.

This dataset relates to the "River water quality" measures on the Environmental Indicators, Te taiao Aotearoa website.