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5. The Proposed Standard

5.1 A 'warrant of fitness' for on-site systems

A national environmental standard is a legally enforceable regulation. The exact wording of this standard will be drafted if the Minister decides to proceed, following this consultation. In essence, the standard will have as its purpose:

[From 1 July 2010] Owners of properties with on-site wastewater systems in locations identified by the regional council will be required to hold a current warrant of fitness (WOF) that confirms their on-site system is functioning properly and is being maintained to an appropriate standard.

The proposed standard would apply only to domestic on-site systems that are operated as permitted activities under rules in a regional plan. It would not include on-site systems servicing businesses, schools, marae, camping grounds, etc. It is assumed that those premises are already monitored by councils under current resource consents. However, your views are sought on whether the proposed standard should cover consented systems or non-domestic on-site systems.

Regional/unitary councils would administer the proposed standard. Each council would be required to undertake an assessment to determine where the proposed standard would apply. The regional council may have to work in conjunction with territorial authorities to gather some of the necessary information. Regional/unitary councils would administer a database of relevant information on the on-site systems, including the outcomes of the regular inspections. They would also be responsible for any follow-up or enforcement action. Regional councils, in agreement with territorial authorities, may transfer their powers to territorial authorities through section 33 of the RMA.

System owners would have the responsibility of ensuring they hold a current warrant of fitness (WOF). They will be responsible for organising and paying for inspections (unless a council chooses to organise the inspections themselves). System owners will also continue to be responsible for the ongoing management and maintenance of their on-site systems. System owners will cover the cost of the WOF inspection as well as continuing to cover the cost of ongoing operation, maintenance and repairs.

Inspectors will be responsible for inspecting on-site systems in accordance with defined criteria on an inspection checklist and accompanying manual. The inspector will issue a WOF where an on-site system passes an inspection (similar to an inspector at a vehicle testing station). The inspector will also be responsible for identifying problems that need remedying to pass a WOF. A fee would be charged for carrying out an inspection.

Figure 6: How the proposed national environmental standard would operate

This figure provides a graphical representation of the roles described in section 5.1.

The WOF system could operate in much the same way a vehicle WOF operates.

  • A WOF would relate to a specific on-site system, and would be issued to the property owner.
  • A WOF would have an expiry date.
  • The owner would have the responsibility for ensuring the system is operated and maintained appropriately throughout the period of the current WOF.
  • A system would need to be re-inspected if any modifications to the system or dwelling (eg, additional rooms) occurred.
  • The WOF check would be underpinned by an inspector’s manual that includes assessment criteria for what constitutes a pass or a fail for each item that requires checking (similar to Land Transport New Zealand’s Vehicle Inspection Requirements Manual).
  • A recognised training course on inspecting on-site systems would be developed for inspectors, similar to that used with inspectors for vehicle WOFs.

To obtain a WOF, an on-site system would first have to pass an inspection check. To pass an inspection, the system would have to achieve a pass for each critical component of a checklist (see Appendix 7). If, during the inspection, only minor maintenance problems were identified (eg, a tank inspection lid was not properly sealed), then a WOF could be issued with recommendations attached. The responsibility for ensuring the ongoing maintenance of a system would remain with the property owner.

A WOF would be valid for three years, with a requirement to be re-inspected on or before the expiry date of the current WOF.

5.1.1 Inspection

The purpose of the inspection would be to check compliance of an on-site system against the main components of an inspection checklist. The inspection checklist would consider the physical condition of a system and look for any problems with the functioning of the system. The person carrying out the inspection would provide the system owner with the results of the inspection (ie, a copy of the checklist). Possible WOF outcomes would be:

  • pass

  • pass with conditions or minor remedial works required

  • fail with substantial remedial works required before re-inspection

  • fail where remediation is not viable and off-site options need to be investigated.

A timeframe for re-inspection would also be supplied.

Regular inspections would:

  • identify on-site systems with critical problems or failures

  • help to identify or confirm the causes of problems that may be affecting the household, the environment or the community, and what can be done to fix them

  • provide for pump-out based on need, ensuring adequate maintenance is carried out, while avoiding fixed-interval pump-outs that can generate excessive volumes of dilute septage and adversely affect the functioning of a system.

The following key pass/fail criteria will be critical for obtaining a WOF for an on-site system.

1 Observation, or evidence, of the discharge of wastewater to the ground surface from any component of an on-site wastewater management system

The discharge may be from drainage pipework, treatment units, land application fields or other sources. This kind of failure creates a direct risk to human health and may allow the discharge of pollutants off-site into neighbouring properties, drains and waterways. Note that the unacceptable discharge of pollutants to groundwater from an on-site system has not been included in these criteria. It is very difficult, and often cost prohibitive, to accurately determine the quantity of pollutants entering groundwater from an individual on-site system. Defining a system as failing due to groundwater contamination is difficult, and the responsibility for developing solutions is often spread among stakeholders rather than focused on the system owner.

2 Gross failure of wastewater treatment and/or conveyance processes

This may include an observed lack of biological activity (and accompanying poor effluent quality and odour), excess accumulation of sludge and scum, or inappropriate dosing rates to a downstream component. Failure of this kind is highly likely to lead to long-term failure of the system to protect public health and the environment.

3 Failure or breakdown of physical system components

This may range from cracked drainage pipework (which also triggers the first criterion), a cracked tank lid, blocked dosing pipework or a trench physically damaged by vehicular traffic. A more detailed checklist will be developed for inspectors in the field to ensure consistency across regions and certainty for making pass and fail decisions.

Figure 7: How the warrant of fitness is issued by means of inspection

The flowchart shows the following process:

  • A desktop study is carried out by the regional council to identify homeowners that will be required to hold a WOF.
  • WOF inspections are carried out on properties with on-site systems that are required by the regional council to hold a WOF. The inspection  covers the matters described in section 5.1.1
  • If the system passes a WOF will be issued and a re-inspection date set for three years time. 
  • If the system fails the homeowner will be required to fix the problems identified by the inspection within a set time limit.
  • If the problems are fixed then a WOF will be issued.  This may or may not require a further inspection depending on the reason for the initial failure.
  • If the problem is not fixed within the time limit or repair or remediation is not possible, then the council will decide the next steps

An on-site system may receive a conditional pass if an immediate pump-out is necessary or minor repairs are required (eg, a vent is broken and needs repair). The WOF will then be issued upon evidence that the pump-out or minor repairs have been completed (this could be a WasteTRACK entry or a receipt from the waste contractor indicating a pump-out has occurred, see Appendix 4). This means a follow-up inspection would only be required if it was deemed necessary.

If an on-site system fails an inspection, the system owner will be notified of the failure and the reason(s) for it, as identified by the inspector. A failure could be the result of a simple lack of maintenance that requires only minor attention, such as a clogged outlet filter that needs servicing for the system to be operating effectively. A failure may also occur because of more significant problems that may require repairs or replacement to part or all of a system.

If a system fails an inspection, the owner will be given a certain time period, depending on the nature of the failure, to remedy the problem and obtain a WOF. The timeframe for fixing problems will depend on the severity of the problem and the environmental effects the failure is causing (see Table 4 below). If the system is causing severe pollution or poses a significant health risk, the property owner may also face other actions by the regional council under the RMA (such as an abatement notice, enforcement order or prosecution). The system owner will have to show the failures have been remedied to be issued with a WOF. The system would not necessarily require a complete re-inspection − the focus would be on the elements that failed the initial inspection.

If, after the agreed time period, the owner has not remedied the deficiencies and obtained a current WOF, he or she will be in a position of non-compliance. The regional council would then decide how to address the non-compliance. In other words, the situation would default to the existing enforcement regime under the RMA. (If an on-site system is in non-compliance, it is likely that it will also be in breach of a permitted activity rule for the region.)

5.1.2 Enforcement

The proposed standard would be enforced by regional councils. The legal process for non-compliance with a national environmental standard would be to issue an abatement notice under section 322(1)(a)(i) of the RMA or apply for an enforcement order under section 314(1)(a) of the RMA. Prosecution by the council for continued non-compliance with the abatement notice or enforcement order could be a last resort. For example, councils could issue an abatement notice for failure to comply with the requirements of the standard, which could include additional time that may be needed by a property owner to remedy a problem. On the other hand, where an area is scheduled to be connected to a reticulated treatment system in the near future, requiring costly repairs may not be appropriate, so councils need to be able to exercise their discretion.

The specification of a time period within which remedial action is to be carried out would prevent a system owner becoming immediately exposed to enforcement action if their system did not pass the initial inspection. This approach provides flexibility for situations where, for example, a local council is considering reticulation for a community, or where a property owner may not be financially able to address a problem within six months.

Table 4: Examples of possible deadlines to fix problems

Nature of system failure

Deadline for fixing problem

Ponding of effluent and or effluent entering a waterway

Immediately (within 30 days)

Treatment unit scum/sludge capacity full and requires immediate pump-out

Immediately (within 30 days)

Land application system failing and requires remediation or replacement

2 to 4 months

Treatment unit and/or land application system has insufficient capacity to cope with inflows and requires upgrade or replacement

Due to costs, up to six months

5.2 Why target only specific areas?

The option of applying a national environmental standard to every property in New Zealand with an on-site system was considered. However, this option has been discarded because an initial cost−benefit assessment indicated that the costs would significantly outweigh any potential benefits. Applying a standard to 'everyone – everywhere' would put significant pressure on local government and other resources, and it is considered more effective to focus resources on high-priority areas.

It is important here to note the significance of cumulative effects. Although the periodic release of insufficiently treated wastewater (containing nutrients and pathogens) from a single on-site system may pose a health risk to people living in the household, it may not adversely affect the environment or lead to off-site effects. Natural processes such as absorption, assimilation, filtration and die-off of organisms may render the impact of a discharge undetectable. However, when the influence of a number of systems is combined, the cumulative risks to human health and the cumulative effects on the environment can be significant. This is why a refinement of the initial proposal has been developed that would target a national environmental standard, focusing on areas that have known problems with the performance of on-site systems or where there is an actual or potential risk to the environment from on-site systems. This focus is thus on areas where there would be the greatest benefit.

5.3 What the proposed national environmental standard does not cover

The proposed standard does not cover:

  • the qualification of inspectors – this would be developed separately and sit outside the standard

  • cluster systems or decentralised systems – these generally require resource consents, with their own monitoring conditions attached

  • hotels, motels, camping grounds, restaurants, schools and marae – these generally require resource consents with their own monitoring conditions attached

  • design of on-site systems – this is covered through the Building Act and guidelines (AS/NZS 1547:2000 and 1546 suite of standards; TP58)

  • installation of on-site systems – this is covered through the Building Act

  • maintenance contracts or servicing – service agents check the internal components, but do not always check the public health and environmental impacts of effluent disposal

  • certification/accreditation of on-site systems – SWANS-SIG15 proposes to act as the national auditing and information storage body (there is a trial site for this in Rotorua)

  • decisions on when a community should move to reticulation

  • educating property owners about how to operate on-site systems – most councils already have very good educational material.


  1. Do you have any general comments about the proposed standard for the inspection and maintenance of on-site wastewater systems?
  2. Should the proposed standard apply to private dwellings only, or should it apply to all on-site systems (including consented systems) that treat domestic wastewater, including hotels, motels, camping grounds, restaurants, schools and marae?
  3. Do you agree with the inspection interval of three years?
  4. Should inspections be coupled with an immediate pump-out?
  5. Do you agree with the proposed critical components for the checklist (see Appendix 7)?
  6. Should the proposed standard prescribe a minimum level of treatment (eg, secondary) for new on-site systems? (Note: This could have the effect of banning the installation of new septic tanks in favour of treatment systems that provide greater levels of treatment.

15 Small Wastewater and Natural Systems Special Interest Group.