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Proposed national environmental standard for on-site wastewater systems

Consultation on the proposed National Environmental Standard for On-site Wastewater Systems closed on 26 September 2008.

During the submission period 14 public workshops were held throughout New Zealand, which were attended by around 300 people. Altogether 135 written submissions were received on the proposal.

The Ministry has prepared a report on submissions that is available now.

Brief summary of proposed standard

The Government is considering developing a national environmental standard (regulations) for the inspection of on-site wastewater systems (such as septic tanks). This is part of the Government’s work to improve the state of our fresh water.

The aim of the proposed standard is to improve the management and environmental performance of domestic on-site wastewater systems. In essence, the proposal is that:

Owners of properties with on-site wastewater systems in specific locations will be required to hold a current warrant of fitness that confirms their on-site system is functioning properly and is being maintained to an appropriate standard.

The standard would authorise regional councils to require property owners with an on-site wastewater system to hold a current warrant of fitness (WOF) for their system.  To obtain a WOF, a system would have to pass an inspection every three years.

Regional councils would identify the areas where the standard would apply.

Main points raised by submitters

The objective of the proposed standard is widely supported, but a number of concerns were raised about the proposal:

  • The standard should cover the issues around on-site wastewater systems more holistically, for example by also addressing design and installation
  • Existing tools should be used instead of a national environmental standard (e.g. district council by-laws, Building Act, improvements to subdivision and building consent processes)
  • Some implementation aspects of the proposed standard should be amended (e.g. administration of standard by territorial authorities not regional councils)
  • The flexibility in how, and where, the proposed standard is applied should be maintained
  • Concerns about significant costs and lack of financial assistance for councils and low income New Zealanders.

Background

On-site wastewater systems provide treatment of domestic wastewater and return it to the environment within the boundaries of the property of origin. It has been estimated that in some regions at least 20 per cent of homes rely on on-site wastewater treatment. On-site wastewater systems can include primary, secondary and tertiary treatment systems. Septic tanks are mainly primary treatment systems and they represent the majority of on-site wastewater systems installed in New Zealand.

For many areas in New Zealand, wastewater systems do not provide an adequate level of treatment and are adversely impacting on human health and the environment. Failing systems can:

  • contribute to lakes, rivers, estuaries and beaches becoming unfit for swimming, gathering seafood and marine farming
  • lead to contamination of groundwater and surface water supplies — affecting the quality of drinking water — and may increase the occurrence of algal blooms.

These effects occur because of a range of factors including: poor maintenance, sensitive receiving environments (lakes, rivers, streams, etc), high density residential areas, shallow groundwater and unsuitable soil types.  Regular inspections and maintenance can play a significant role in improving the performance of wastewater systems.

For more information, see:

Next steps

The Ministry for the Environment is considering options to amend the proposed national environmental standard based on the feedback received during the consultation. A revised and expanded cost-benefit analysis is being prepared. Alternative options to a national environmental standard are also being considered both within and outside the scope of the Resource Management Act.

Further information

Last updated: 16 April 2009