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Unnamed Trib of Waipu at d/s Ratana STP

This is the impact monitoring site for the authorised discharge from the Ratana wastewater treatment plant. The treatment plant services a population of 327 and treats wastewater to a tertiary level.

Water Quality
Water quality data for this site
Can I trust this data?

This dashboard shows information on the data collected by the regional councils for water quality indicators, analysed as state and trend.

  • State

    State shows how the median of samples from this site compares to other sites.

    This site is a {{siteDescription}} site. Currently showing the state of this site compared to:

  • The state is also represented by comparison to the National Objectives Framework (NOF) in the National Policy Statement for Freshwater Management 2020  for some indicators.

  • Trend

    Trend shows how the quality of water is changing over time. Depending on the sampling history duration, five, ten and fifteen year timescales are available:

The state is also represented by comparison to the National Objectives Framework (NOF) in the National Policy Statement for Freshwater Management 2020  for some indicators.


Can I trust this data?

The Cawthron Institute has worked alongside regional councils to verify the processes and methods used for data collection, laboratory analysis of samples collected and the statistical analysis and interpretation of the results presented.

If all Cawthron ticks are green, then you can trust this data. However, if one or more ticks are orange, then conclusions should be treated with some caution.

For more details on each tick, see our 'Can I Trust This Data?' Factsheet.

Can I trust the data for this site?
Data Collection

All samples were collected using approved field protocols and have been analysed in accredited laboratories. Therefore the data shown here has been collected and analysed following best practice.

State

All samples were collected using approved field protocols and have been analysed in accredited laboratories.

Trend - SAMPLING FREQUENCY

The majority of trend calculations for this council are based on monthly data. Sites with more data points generally have greater ‘statistical power’ for trends to be detected. Therefore, any trends shown here are based on best practice in terms of sampling frequency based on Davies-Colley et al. (2012).

Bacteria

E. coli
{{medianValue('ECOLI')}}
State
{{stateMsg(ECOLI.StateScore)}}
State
{{ECOLI.NofBand | uppercase}}
NOF Band
N/A
NOF Band
Trend
{{trendMsg(ECOLI)}}

Sample history at this site

Showing:
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E. coli samples for Unnamed Trib of Waipu at d/s Ratana STP
n/100ml

What is this graph showing me?

This graph is displaying E. coli concentrations over the selected time period. You can adjust this period by changing the dropdowns. These records form the basis for the state and trend indicators displayed on the dashboard. 

Find out about how State and Trend are calculated.

What do the NOF icons mean?

The bands for E. coli are as outlined in the NOF for freshwater:

A
For at least half the time, the estimated risk is <1 in 1000 (0.1% risk). The predicted average infection risk is 1%*.
B
For at least half the time, the estimated risk is <1 in 1000 (0.1% risk). The predicted average infection risk is 2%*.
C
For at least half the time, the estimated risk is <1 in 1000 (0.1% risk). The predicted average infection risk is 3%*.
D
20-30% of the time, the estimated risk is >=50 in 1000 (>5% risk). The predicted average infection risk is >3%*.
E
For more than 30% of the time, the estimated risk is >=50 in 1000 (>5% risk). The predicted average infection risk is >7%*.
* The predicted average infection risk is the overall average infection to swimmers based on a random exposure on a random day, ignoring any possibility of not swimming during high flows or when a surveillance advisory is in place (assuming that the E. coli concentration follows a lognormal distribution). Actual risk will generally be less if a person does not swim during high flows.
 Download data

Clarity

Black disc
{{medianValue('BDISC')}}
State
{{stateMsg(BDISC.StateScore)}}
Trend
{{trendMsg(BDISC)}}

Sample history at this site

Showing:
–
Black Disc samples for Unnamed Trib of Waipu at d/s Ratana STP
metres

What is this graph showing me?

This graph is displaying Black Disc readings over the selected time period. You can adjust this period by changing the dropdowns. These records form the basis for the state and trend indicators displayed on the dashboard. 

Find out about how State and Trend are calculated.

 Download data
Turbidity
{{medianValue('TURB')}}
State
{{stateMsg(TURB.StateScore)}}
Trend
{{trendMsg(TURB)}}

Sample history at this site

Showing:
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Turbidity samples for Unnamed Trib of Waipu at d/s Ratana STP
 NTU
FNU

What is this graph showing me?

This graph is displaying Turbidity levels over the selected time period. You can adjust this period by changing the dropdowns. 

Yellow coloured bars on the graph represent turbidity values measured in NTU. These records form the basis for the state and trend indicators displayed on the dashboard. Some councils now also measure turbidity in FNU.  These data are shown as blue coloured bars and are not used by LAWA for the state and trend indicators.

Find out about how State and Trend are calculated.

 Download data

Nitrogen

Total Nitrogen
{{medianValue('TN')}}
State
{{stateMsg(TN.StateScore)}}
Trend
{{trendMsg(TN)}}

Sample history at this site

Showing:
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Total Nitrogen samples for Unnamed Trib of Waipu at d/s Ratana STP
g/m3

What is this graph showing me?

This graph is displaying Total Nitrogen concentrations over the selected time period. You can adjust this period by changing the dropdowns. These records form the basis for the state and trend indicators displayed on the dashboard. 

Find out about how State and Trend are calculated.

 Download data
Total Oxidised Nitrogen
{{medianValue('TON')}}
State
{{stateMsg(TON.StateScore)}}
Trend
{{trendMsg(TON)}}

Sample history at this site

Showing:
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Total Oxidised Nitrogen samples for Unnamed Trib of Waipu at d/s Ratana STP
g/m3

What is this graph showing me?

This graph is displaying Total Oxidised Nitrogen concentrations over the selected time period. You can adjust this period by changing the dropdowns. These records form the basis for the state and trend indicators displayed on the dashboard. 

Find out about how State and Trend are calculated.

 Download data
Ammoniacal Nitrogen
{{medianValue('NH4')}}
State
{{stateMsg(NH4.StateScore)}}
State
{{NH4.NofBand | uppercase}}
NOF Band
N/A
NOF Band
Trend
{{trendMsg(NH4)}}

Sample history at this site

Showing:
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Ammoniacal Nitrogen samples for Unnamed Trib of Waipu at d/s Ratana STP
g/m3

What is this graph showing me?

This graph is displaying Ammoniacal Nitrogen concentrations over the selected time period. You can adjust this period by changing the dropdowns. These records form the basis for the state and trend indicators displayed on the dashboard. 

Find out about how State and Trend are calculated.

What do the NOF icons mean?

The bands for Ammoniacal Nitrogen are as outlined in the NOF for freshwater:

A
99% species protection level: No observed effect on any species tested.
B
95% species protection level: Starts impacting occasionally on the 5% most sensitive species.
National bottom line: Annual median 0.24 mg NH4-N/L. Annual maximum 0.40 mg NH4-N/L (milligrams ammoniacal-nitrogen per litre). Note 1 mg/l = 1 g/m3
C
80% species protection level: Starts impacting regularly on the 20% most sensitive species (reduced survival of most sensitive species).
D
Starts approaching acute impact level (ie risk of death) for sensitive species.
 Download data

Phosphorus

Dissolved Reactive Phosphorus
{{medianValue('DRP')}}
State
{{stateMsg(DRP.StateScore)}}
State
{{DRP.NofBand | uppercase}}
NOF Band
N/A
NOF Band
Trend
{{trendMsg(DRP)}}

Sample history at this site

Showing:
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Dissolved Reactive Phosphorus samples for Unnamed Trib of Waipu at d/s Ratana STP
g/m3

What is this graph showing me?

This graph is displaying Dissolved Reactive Phosphorus concentrations over the selected time period. You can adjust this period by changing the dropdowns. These records form the basis for the state and trend indicators displayed on the dashboard. 

Find out about how State and Trend are calculated.

What do the NOF icons mean?

The bands for Dissolved Reactive Phosphorus are as outlined in the NOF for freshwater:

A
Ecological communities and ecosystem processes are similar to those of natural reference conditions. No adverse effects attributable to dissolved reactive phosphorus (DRP) enrichment are expected.
B
Ecological communities are slightly impacted by minor DRP elevation above natural reference conditions. If other conditions also favour eutrophication, sensitive ecosystems may experience additional algal and plant growth, loss of sensitive macroinvertebrate taxa, and higher respiration and decay rates.
C
Ecological communities are impacted by moderate DRP elevation above natural reference conditions. If other conditions also favour eutrophication, DRP enrichment may cause increased algal and plant growth, loss of sensitive macroinvertebrate and fish taxa, and high rates of respiration and decay.
D
Ecological communities impacted by substantial DRP elevation above natural reference conditions. In combination with other conditions favouring eutrophication, DRP enrichment drives excessive primary production and significant changes in macroinvertebrate and fish communities, as taxa sensitive to hypoxia are lost.
 Download data
Total Phosphorus
{{medianValue('TP')}}
State
{{stateMsg(TP.StateScore)}}
Trend
{{trendMsg(TP)}}

Sample history at this site

Showing:
–
Total Phosphorus samples for Unnamed Trib of Waipu at d/s Ratana STP
g/m3

What is this graph showing me?

This graph is displaying Total Phosphorus concentrations over the selected time period. You can adjust this period by changing the dropdowns. These records form the basis for the state and trend indicators displayed on the dashboard. 

Find out about how State and Trend are calculated.

 Download data

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