Lake water quality trends, 2004-2013

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Creative Commons Attribution 3.0 New Zealand

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6507
88
Added
29 Sep 2015

This dataset was first added to MfE Data Service on 29 Sep 2015.

When nutrients accumulate in lakes (referred to as ‘nutrient enrichment’) above certain levels, they can make the lakes murky and green with algae, and lower oxygen levels. Lakes with extremely poor water quality are rarely suitable for recreation and provide poor habitats for aquatic species.

Trends in the following parameters are provided:
Trophic Level Index 3 (TLI)
Chlorophyll-a (CHLA)
Bottom-water dissolved oxygen (DObottom)
Ammoniacal nitrogen (NH4N)
Oxidised nitrogen (NO3N)
Total nitrogen (unfiltered) (TN)
Dissolved reactive phosphorus (DRP)
Total phosphorus (unfiltered) (TP)

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/DDui3u from the Ministry for the Environment dataservice.

This dataset relates to the "Lake water quality: Trophic Level Index" measure on the Environmental Indicators, Te taiao Aotearoa website.

Table ID 52538
Data type Table
Row count 3724
Services Web Feature Service (WFS), Catalog Service (CS-W), data.govt.nz Atom Feed

Lake water quality trends data quality

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Creative Commons Attribution 4.0 International

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16 Apr 2019

This item was first added to MfE Data Service on 16 Apr 2019

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Document ID21927
File namelake-water-quality-trends-data-quality.pdf
TypePDF
Size517 KB

Lake water quality trends data quality

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Creative Commons Attribution 4.0 International

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You must attribute the creator in your own works.

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16 Apr 2019

This item was first added to MfE Data Service on 16 Apr 2019

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Document ID21934
File namelake-water-quality-trends-data-quality.pdf
TypePDF
Size517 KB

Lake water quality trends 2008–2017 1998–2017 and 1990–2017

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Creative Commons Attribution 4.0 International

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5229
21
Added
16 Apr 2019

This dataset was first added to MfE Data Service on 16 Apr 2019.

This dataset contains ten lake water quality variables based on measurements made at monitored lake sites: chlorophyll-a, nitrate-nitrogen, total nitrogen, ammoniacal nitrogen, dissolved reactive phosphorus, total phosphorus, Escherichia coli, water clarity, and lake trophic level index (TLI3 and TLI4). 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 When nitrogen and phosphorus accumulate above certain concentrations in lakes (referred to as ‘nutrient enrichment’), they can stimulate excessive growth of algae and cyanobacteria. Chlorophyll-a is a measure of the phytoplankton (algae) biomass. The lake trophic level index (TLI) indicates the health of a lake based on concentrations of three variables:
· total nitrogen
· total phosphorus
· chlorophyll-a.

Water clarity is a measure of underwater visibility. Lakes with poor clarity and TLI are poor habitats for some species of animals and plants, and they may not be suitable for recreation. Ammoniacal nitrogen can be toxic to aquatic life if concentrations are high enough.

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...

Table ID 99873
Data type Table
Row count 609
Services Web Feature Service (WFS), Catalog Service (CS-W), data.govt.nz Atom Feed

Lake water quality state percentiles, by monitoring site, 2009-2014

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Creative Commons Attribution 3.0 New Zealand

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You must attribute the creator in your own works.

6856
60
Added
29 Sep 2015

This dataset was first added to MfE Data Service on 29 Sep 2015.

When nutrients accumulate in lakes (referred to as ‘nutrient enrichment’) above certain levels, they can make the lakes murky and green with algae, and lower oxygen levels. Lakes with extremely poor water quality are rarely suitable for recreation and provide poor habitats for aquatic species.

Percentile calculations for the following parameters are provided:
Trophic Level Index 3 (TLI)
Chlorophyll-a (CHLA)
Bottom-water dissolved oxygen (DObottom)
Ammoniacal nitrogen (NH4N)
Oxidised nitrogen (NO3N)
Total nitrogen (unfiltered) (TN)
Dissolved reactive phosphorus (DRP)
Total phosphorus (unfiltered) (TP)

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/DDui3u from the Ministry for the Environment dataservice.

This dataset relates to the "Lake water quality: Trophic Level Index" measure on the Environmental Indicators, Te taiao Aotearoa website.

Table ID 52537
Data type Table
Row count 5632
Services Web Feature Service (WFS), Catalog Service (CS-W), data.govt.nz Atom Feed

Lake water quality state 2013–2017 raw data

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Creative Commons Attribution 4.0 International

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You must attribute the creator in your own works.

384
32
Added
16 Apr 2019

This item was first added to MfE Data Service on 16 Apr 2019

Document ID21926
File namelake-water-quality-state-20132017-raw-data.csv
TypeCSV
Size174 KB

Lake water quality state 2013–2017 data quality

Licence

Creative Commons Attribution 4.0 International

You may use this work for commercial purposes.

You must attribute the creator in your own works.

370
14
Added
16 Apr 2019

This item was first added to MfE Data Service on 16 Apr 2019

3
Document ID21925
File namelake-water-quality-state-20132017-data-quality.pdf
TypePDF
Size504 KB

Lake water quality state 2013–2017

Licence

Creative Commons Attribution 4.0 International

You may use this work for commercial purposes.

You must attribute the creator in your own works.

5570
28
Added
16 Apr 2019

This dataset was first added to MfE Data Service on 16 Apr 2019.

This dataset contains ten lake water quality variables based on measurements made at monitored lake sites: chlorophyll-a, nitrate-nitrogen, total nitrogen, ammoniacal nitrogen, dissolved reactive phosphorus, total phosphorus, Escherichia coli, water clarity, and lake trophic level index (TLI3 and TLI4). 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 When nitrogen and phosphorus accumulate above certain concentrations in lakes (referred to as ‘nutrient enrichment’), they can stimulate excessive growth of algae and cyanobacteria. Chlorophyll-a is a measure of the phytoplankton (algae) biomass. The lake trophic level index (TLI) indicates the health of a lake based on concentrations of three variables:
· total nitrogen
· total phosphorus
· chlorophyll-a.
Water clarity is a measure of underwater visibility. Lakes with poor clarity and TLI are poor habitats for some species of animals and plants, and they may not be suitable for recreation. Ammoniacal nitrogen can be toxic to aquatic life if concentrations are high enough.

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....

Table ID 99872
Data type Table
Row count 454
Services Web Feature Service (WFS), Catalog Service (CS-W), data.govt.nz Atom Feed

Lake Water Quality for Swimming Categories [Raw Model Output]

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Creative Commons Attribution 4.0 International

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You must attribute the creator in your own works.

1290
7
Added
27 Jun 2018

This dataset was first added to MfE Data Service on 27 Jun 2018.

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.

Layer ID 95561
Data type Vector multipolygon
Feature count 3801
Services Vector Query API, Web Feature Service (WFS), Catalog Service (CS-W)

Lake water quality 28 year trends, raw data

Licence

Creative Commons Attribution 4.0 International

You may use this work for commercial purposes.

You must attribute the creator in your own works.

327
3
Added
16 Apr 2019

This item was first added to MfE Data Service on 16 Apr 2019

Document ID21930
File namelake-water-quality-28-year-trends-raw-data.csv
TypeCSV
Size23.8 KB
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