Compliance Explained

Use this page to understand the compliance details as listed against a particular supply. For a more general explanation of compliance with the Drinking-Water Standards, see the compliance monitoring page.

Compliance with What?

Community drinking-water supplies in New Zealand are expected to demonstrate compliance with the New Zealand Drinking-Water Standards 2005 or 2000. These specify water monitoring (ie taking samples for testing) and other requirements for supplies, both at the treatment plant and within the distribution zone itself.

The number of samples to be tested varies depending upon the size of the community, the quality of source water being used (eg deep groundwater versus river or lake water), and the treatments and risk-minimising processes that are in place.

Compliance with the Standards is measured by looking at how the zone or plant meets the requirements for a 12 month period. Data on this website is from a survey for the 12 month period from 1 July 2009 to 30 June 2010, which is the latest period for which data has been publicly released.

The Ministry of Health website has the full report for the 2009/10 year which you can download as a set of pdf files. Alternatively, check our Official Documents page for earlier years.

How to Read a Compliance Page

The short answer: Read the colour code. Green is good, red is bad, and other colours are somewhat in-between.
For the full story, read on ...

Compliance in the Distribution Zone

Compliance is concerned here with E. coli compliance

Status or comment	Explanation
Yes	Meets compliance requirements for E. coli
From month year	Meets compliance requirements for E. coli from this month onwards. (This option aims to encourage previously non-compliers to improve their monitoring at the earliest opportunity, and to be recognised for that.)
No	Fails to comply - either because the water quality was shown to be inadequate, or because the monitoring programme was insufficent to demonstrate otherwise. More on possible reasons.
No data available	The supply is newly registered, or has been restructured in some way, so that the current active zones are different to those active at the time of the Annual Review.
DWSNZ 2000	Drinking Water Standards for New Zealand 2000 Download available
DWSNZ 2005	Drinking Water Standards for New Zealand 2005 (Revised 2008) Download available
2000 Crit. 2A	Criteria for E. coli monitoring (as specified in DWSNZ 2000)
2000 Crit. 2B	Criteria for free available chlorine (FAC) or chlorine dioxide, combined with E. coli monitoring
2005 Crit. 6A	Criteria for E. coli monitoring (as specified in DWSNZ 2005)
2005 Crit. 6B	Criteria for free available chlorine (FAC) or chlorine dioxide, combined with E. coli monitoring
2005 PHRMP	Criteria using Public Health Risk Management Plans, as specified in Chapter 10 of DWSNZ 2005. These are alternative compliance criteria available to certain supplies serving up to 500 people.

Priority 2 Determinands Compliance at the Zone

The Distribution Zone Compliance entries on this website are only for E. coli. If a supply has Priority 2 determinands listed against it (eg "Test for: Lead, Nickel" on its Compliance or Register structure), then it needs to monitor for those determinands as well. Details of Priority 2 compliance will be added to this website in the future.

Compliance at the Treatment Plant

1. E. coli Compliance at the Plant

While following the zone compliance pattern, plant compliance is more complicated because E. coli compliance in some chlorinated supplies can be demonstrated by continuous monitoring of FAC rather than sampling for E. coli.

FAC stands for "Free Available Chlorine", which is the residual disinfection capability remaining in the water as it leaves the plant. If continuous FAC is measured, then turbidity and pH must also be at acceptable levels and measured continuously as well.

Status or comment	Explanation
Yes	Meets compliance requirements for E. coli
No	Fails to comply - either because the water quality was shown to be inadequate, or because the monitoring programme was insufficent to demonstrate otherwise. More on possible reasons.
Exempt	No E. coli monitoring is required for some small supplies (up to 3 buildings) where the plant is close to the reticulation. The plant compliance is therefore assumed to be as for the zone compliance.
Off	The plant did not supply water during this year.
No data available	The supply is newly registered, or has been restructured in some way, so that the current active plants are different to those active at the time of the Annual Review.
DWSNZ 2000	Drinking Water Standards for New Zealand 2000 Download available
DWSNZ 2005	Drinking Water Standards for New Zealand 2005 (Revised 2008) Download available
2000 Crit. 1A	Criteria for E. coli monitoring (as specified in DWSNZ 2000)
2000 Crit. 1B	Criteria for continuous FAC monitoring
2005 Crit. 1	Criteria for E. coli monitoring (as specified in DWSNZ 2005)
2005 Crit. 2A	Criteria for continuous FAC monitoring
2005 Crit. 2B	Non-continuous FAC and E. coli monitoring
2005 Crit. 3	Continuous chlorine dioxide monitoring
2005 Crit. 4	Ozone and E. coli monitoring
2005 Crit. 5	UV monitoring
2005 PHRMP.	Criteria using Public Health Risk Management Plans, as specified in Chapter 10 of DWSNZ 2005.

2. Protozoa Compliance at the Plant

Protozoa (Giardia and Cryptosporidium) compliance is also required at the Plant. Since it is difficult and expensive to directly determine these, protozoa compliance is based upon evidence of adequate barriers in place to keep these organisms from the supply.

In brief, these methods include one of:

coagulation/flocculation treatment, with effectiveness confirmed by low turbidity.
filtration without coagulation, confirmed by particle analysis
disinfection by ozone or chlorine dioxide
water is from a 'secure' groundwater source

Status or comment	Explanation
Yes	Meets compliance requirements for protozoa
No	Fails to comply - either because the water quality was shown to be inadequate, or because the barriers in place are inadequate to remove protozoa.
No data	No data recorded, or supply restructured since the compliance year.

3. Priority 2 Determinands Compliance at the Plant

As for zones, if a supply has Priority 2 determinands listed against it (eg "Test for: Lead, Nickel" on its Compliance or Register structure), then it needs to monitor for those determinands as well. Details of plant Priority 2 compliance will be added to this website in the future.

Possible Reasons for E. coli Non-Compliance in the Zone or Plant

Factor	Explanation
Transgressions	E. coli detected in more water samples than the minimum number allowable for a zone or plant of this population.
No samples taken	No E. coli samples taken (or recorded.)
Not enough samples	Some monitoring samples taken, but not enough. (The Standards specify how many and how often, etc.)
Inadequate Scheduling	Enough samples were taken, but either there were excessively long gaps between samples at some dates, or else samples were concentrated on too few days of the week. (For example, if all samples are taken on Mondays, the supply will not comply.)
No evidence that corrective actions were taken	If E. coli transgressions are found in monitoring samples, the water supplier must take appropriate corrective actions to recheck the quality, fix any problems, and if necessary inform health authorities and warn consumers.
Corrective Actions taken, but delayed	Corrective actions taken too slowly to meet the requirements of the Standards and to minimise the potential risk to consumers.
Not a recognised laboratory	Only samples analysed by a Ministry of Health recognised laboratory are acceptable for demonstrating compliance. Who are these laboratories?

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