Freshwater Layers

Note that this is a large dataset so is provided as a shapefile, and will need a GIS application to view.

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) modelled for New Zealand’s river length, expressed as percentiles for the period of 2016–2020

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...

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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) modelled for New Zealand’s river length, expressed as percentiles for the period 2016–2020

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: clarity and turbidity" indicator (available atwww.stats.govt.nz/indicators/river-water-quality-c...).

This dataset contains two attributes of water quality based on measurements made at monitored river sites:

• Clarity
• Turbidity

Clarity and turbidity 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:

• clarity and turbidity as modelled median values for New Zealand’s river length for the period 2016–2020

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 atenvironment.govt.nz/publications/environment-aotea... .

Note that this is a large dataset so is provided as a shapefile, and will need a GIS application to view.

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 modelled data for rivers:

• 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 modelled for New Zealand’s river segments without monitor sites for the period 2016–2020

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....

Note that this is a large dataset so is provided as a shapefile, and will need a GIS application to view.

Note that this is a large dataset so is provided as a shapefile, and will need a GIS application to view.

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...).

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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 modelled median values for New Zealand’s river length for the period 2016–2020

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....

Raster layer with 100m * 100m pixels, Each pixel represents the estimated nitrate-N leached in kg/ha/yr. This layer contains all nitrate leaching estimated from sheep.

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.

Raster layer with 100m * 100m pixels, Each pixel represents the estimated nitrate-N leached in kg/ha/yr. This layer contains all nitrate leaching estimated from deer.

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.

Raster layer with 100m * 100m pixels, Each pixel represents the estimated nitrate-N leached in kg/ha/yr. This layer contains all nitrate leaching estimated from beef cows.

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.

Raster layer with 100m * 100m pixels, Each pixel represents the estimated nitrate-N leached in kg/ha/yr. This layer contains all nitrate leaching estimated from dairy cows.

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.

Water quality for swimming categories for lakes with perimeters over 1.5 km. This dataset was used to compose the current state for water quality for swimming.

Note this data is under review and will be updated in due course. This information is based on modelled and measured data using the approach outlined at
www.mfe.govt.nz/fresh-water/freshwater-management-...

The modelling methods used are outlined in Snelder et al. (2016) Strategic assessment of New Zealand’s freshwaters for recreational use: a human health perspective. LWP Client Report 2016-011 www.mfe.govt.nz/publications/fresh-water/strategic...

Versions

This dataset is the geometric version of this: data.mfe.govt.nz/table/53620-river-water-quality-f...

This dataset has now been superseded due to consultation with local authorities, and this is the latest version: data.mfe.govt.nz/layer/95555-river-water-quality-f...

Column headings:

LID: FENZ Lake ID

Name: Name of lake (where available

RC: Regional council name

CHLA: Chlorophyll a (mg/L)

SECCHI: Secchi disc depth (m)

TLI3: Trophic Level Index (unitless)

TN: Total nitrogen (mg/m3)

TP: Total phosphorus (mg/m3)

CyanBVl: Cyanobacterial biovolume (mm3/L)

Cy_cat: Water quality for swimming category see www.mfe.govt.nz/fresh-water/what-government-doing/...

Note: blank cells are reaches where a prediction was not possible because of missing predictor variables.