Groundwater quality, state, 2014-18

Licence

Creative Commons Attribution 4.0 International

You may use this work for commercial purposes.

You must attribute the creator in your own works.

698
16
Updated
11 Jun 2021

This dataset was last updated on MfE Data Service on 11 Jun 2021.

11 June 2021: A revised version of this dataset has been published to correct the terminology used to compare nitrate-nitrogen values to the 3 g/m3 guideline value. The field name has been changed from “reference_condition” to “n_n_guideline”, and values in this field will now be either “Does not exceed” or “Exceeds”, instead of “Meets” or “Does not meet”.

20 July 2020: We corrected the data about drinking water standards for E. coli and nitrate-nitrogen in the key findings for groundwater quality.

For the five-year period 2014‒2018:

  • 68 percent of 364 sites failed to meet the E.coli drinking water standards (changed from 98 percent of 145 sites failed to meet the E. coli drinking water standards)
  • 19 percent of 433 sites didn’t meet nitrate-nitrogen standards (changed from 28 percent of 403 sites failed to meet the nitrate-nitrogen drinking water standards).

This indicator measures groundwater quality in New Zealand’s aquifers and how it is changing over time, based on measurements made at monitored sites. We report on nitrate-nitrogen, ammoniacal nitrogen, dissolved reactive phosphorus, chloride, conductivity and Escherichia coli (E. coli) including:

  • median values for the period 2014–18
  • nitrate-nitrogen median values compared to a guideline value of 3 grams per cubic metre (g/m3). This value is defined as a concentration that indicates groundwater has been influenced by industrialised agriculture and is highly likely to have been impacted by human activity (per Morgenstern & Daughney, 2012 and Daughney & Reeves, 2005).
  • the proportion of samples from each site that have concentrations of nitrate-nitrogen or E. coli in excess of the Maximum Acceptable Values for protection of human health (Ministry of Health, 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.

License

Creative Commons Attribution 4.0 International

You may use this work for commercial purposes.

You must attribute the creator in your own works.

Attachments
1. Groundwater_quality_state_data_quality_report 210 KB pdf
Technical Details
Table ID 104569
Data type Table
Row count 14644
Columns site, region, period_start, period_end, period, measure, data_value, percentile, units, measurements_per_site, years_collected_per_site, dwsnz_meet_percent, dwsnz_exceed_percent, dwsnz_exceed_percent_bins, n_n_guideline, lat, long
Services Web Feature Service (WFS), Catalog Service (CS-W), data.govt.nz Atom Feed
History
Added 7 Apr 2020
Last updated 11 Jun 2021
Revisions 10 - Browse all revisions
Current revision Imported on June 11, 2021 from CSV .