Treating Risks: RMA Tools for Managing Natural Hazards

Once a hazard has been identified, the significance of the risk evaluated, and a decision made to treat the risk, the next decision is deciding how best to treat [manage] the hazard risk.

This section outlines the RMA tools for managing hazard risk, but it is important to also consider the non-RMA tools available to manage hazards. Ideally, there should be an integrated and coordinated approach using a combination of RMA and non-RMA tools.

National policy statements and national environmental standards

National policy statements (NPSs) (prepared under Part 5 of the RMA) can provide direction to local government on how competing national benefits and local costs should be balanced. National environmental standards (NESs) are regulations that set baseline nationwide minimum standards for particular issues. To date there are no national policy statements or national environmental standards for particular hazards. The New Zealand Coastal Policy Statement 2010 (NZCPS 2010) identifies coastal erosion and other natural hazards as a key issue facing the coastal environment. The NZCPS includes policies on the identification of coastal hazards: subdivision, use and development in areas of coastal hazard risk; natural defences against coastal hazards; and strategies for protecting significant existing development from coastal hazard risk.

Local authorities will need to stay aware of developments at the national level in the event that new NPSs and NESs are developed and consider whether and how to incorporate such documents into their RMA plans and decision-making.

Regional policy statements

Regional policy statements integrate the management of natural and physical resources across a region. The requirement for RMA plans to 'give effect to' regional policy statements makes them particularly influential and useful for coordinating RMA policy responses across two or more territorial authority areas.

To ensure integration with other hazard management activities in a region, the preparation of hazard provisions in a regional policy statement should be linked with work being undertaken, and priorities established, as part of the CDEM Group Plan.

Regional plans

Regional plans can address specific hazard issues relevant to regional council functions including coastal hazards, floodplain management, land stability, and geothermal hazards. A regional council can prepare a specific natural hazard regional plan; however, the interrelated nature of hazards with other environmental features or effects means that natural hazard provisions are generally dispersed amongst various sections of other regional plans.

Regional plans can contain objectives, policies and rules addressing natural hazards. Unlike district councils, regional councils can have rules in regional plans for controlling land (for the purposes of avoiding or mitigating natural hazards) that are exempt from existing use right clauses under s10(4) of the RMA. This makes them particularly useful in managing hazard risk in areas where development has taken place before plan rules to manage risks could be implemented.

Regional plans generally include rules requiring resource consents and set out specific objectives and policies against which such consents are measured.

District plans

Every territorial authority is required to prepare a district plan for its district. District plans are required to give effect to regional policy statements. Territorial authorities, when reviewing their district plan, need to be conscious of the direction outlined in a regional policy statement, and how that should be implemented through their district plan.

Even if no direction is provided through the regional policy statement, a district plan should include risk-based objectives, policies and rules to control the effects of the use of land for the avoidance or mitigation of natural hazards.

Zones and overlays within district plan maps can identify the location of specific hazards within a city/district and specific requirements can be applied to these areas. See the section on Hazards Mapping for more information about how to identify and map hazards.

A local authority should provide:

  • clear direction through plans and other means on the hazard information that needs to be included in any resource consent application
  • policies within the plan giving clear guidance on the matters addressed during consideration of a resource consent and the desired outcome sought in managing hazard risk.

Note that rules in district plans may be rendered less effective in controlling development in hazard prone areas where existing use rights apply. In circumstances where the management of both existing and new development through RMA plan rules is desired, regional and territorial authorities may need to work together on an integrated approach that uses a combination of regional and district plan provisions.

Iwi management plans/planning documents

Sections 61(2A) and 74(2A) of the RMA require that regional and district plans take into account relevant planning documents recognised by an iwi authority and lodged with the council.

An iwi management plan is a policy document that identifies important issues to iwi regarding the use of natural and physical resources within their area. Māori can have a unique interest in the management of hazards. For example, some hazards and proposed hazard management works may be in areas containing wahi tapu sites and other places of significance for Māori.

Some iwi planning documents can be a useful source of information in relation to past hazard-related events. Linking iwi management plans with council documents (for example, regional policy statements) or processes can help when taking account of iwi concerns with respect to natural hazard management (for example, cultural concerns over diversions of water courses or the location of disposal sites for debris).

Resource consents

Resource consent applications (including any to subdivide, use or develop on, by or near land subject to natural hazard risk) must be accompanied by adequate assessments of environmental effects (AEEs). Clause 2(f) Schedule 4 of the RMA states that an AEE should consider 'any risk to the neighbourhood, the wider community, or the environment through natural hazards'. Where natural hazards are present, it would be good practice for the AEE to:

  • identify the particular hazard present
  • provide a risk analysis of the effects of the activity on the hazard [if one exists], and also how the hazard impacts on the effects of the activity
  • consider alternatives to avoid the hazard (such as locating away from the area affected by the hazard)
  • identify mitigation measures
  • determine the residual risk and include appropriate mitigation to address it.

When assessing applications where hazards are present, it is important to consider the wider context for natural hazards beyond the site. Matters to consider include:

  • risk to life, property and the environment posed by the natural hazard
  • likely frequency and magnitude of the hazard event
  • type, scale and distribution of any potential effects from the natural hazard
  • degree to which the subdivision, use or development activity can avoid or mitigate the effects of the natural hazard
  • accuracy and reliability of any engineering and geotechnical information
  • whether use or development of the land will exacerbate the hazard, whether the hazard is on the same site, or on any adjacent or nearby sites.

Where significant effects from hazards are identified as a result of proposed land development or structures, then appropriate mitigation needs to be identified or the application should be declined (if provisions in the plan allow for the consent to be declined).

A site-specific risk checklist can be used to assess individual consent applications where there are known hazard risks.

Checklist for assessing risk

Identification of hazards

Have all hazards that have the potential to affect the application been considered?

  • Has the primary hazard been identified?
  • Have secondary hazards that could be triggered by primary hazards been considered?

Have cross-boundary hazards been identified, i.e. any risk from neighbouring property?

Analysis and description of hazards

  • What is the chance of occurrence of each hazardous event?
  • How often can it occur?
  • What will the magnitude and length of each hazardous event be?
  • How rapidly can it occur and what warning systems and evacuation procedures are in place?
  • What areas can be affected?

Identify gaps in knowledge and understanding of hazards

  • Have gaps in knowledge or understanding about the hazard and its consequences been identified and explained?
  • Is it imperative that these gaps are filled before the consent process proceeds further?

Identify and describe the important elements of the community and environment

  • Are there any critical facilities (medical and emergency services, fire and police stations) that need special consideration in terms of operation for hazard mitigation or relocation?
  • Are there any engineering facilities (transport, power and water supply, sewerage and telecommunications) that need special consideration?

Describe and analyse the community's vulnerability

  • What is the proximity of the community to hazards?
  • What is the level of access to emergency services?
  • What is the level of awareness within the general community?
  • What is the level of mobility should evacuation be necessary?
  • Are the engineering services (water, sewerage etc.) robust or frail?
  • Have the existing civil defence emergency management response and recovery plans, prepared under the CDEM Act, been tested, and are they adequate?

Identify risks

  • Are all credible risks, including residual risk, identified?
  • Has each risk been identified in such a manner that treatment priorities and treatment requirements can be determined?

Other considerations

  • Has any hazard assessment undergone peer review?
  • Have any identified risks been adequately treated to reduce the risks to acceptable levels?

When there is uncertainty about the risks associated with development then specialist technical advice or a peer report should be sought as part of the assessment of the application. Likewise, technical reports submitted with resource consent applications need to be prepared by a professional qualified to assess hazard risk.

Subdivision, use or development on or near land subject to natural hazard risk can give rise to cumulative effects. These effects need to be considered when considering application for these activities.

Making a decision under section 106 of the RMA

Local authorities can refuse consent for subdivision where the land is subject to certain hazards under s106 of the RMA. When making a decision under s106, councils have to consider whether the land is suitable for subdivision, taking into account any measures proposed by the applicant to protect the land from the effects of natural hazards.

Section 106 requires consideration of whether there is likely to be material damage to land or structures from erosion, falling debris, subsidence, slippage, or inundation from any source. Consideration must also be given to whether 'any subsequent use that is likely to be made of the land is likely to accelerate, worsen, or result in material damage to the land, other land (for example, neighbouring or downstream properties) or structure'.

When making a decision under s106, a council is able to take into account any measures put forward by the applicant. The courts have provided a test for councils to use to determine if measures proposed by an applicant are sufficient to meet the requirements of s106.

Using this test, a council does not have to ensure that the whole of the land is free from the risk of inundation but does have to ensure that in its judgement the land is sufficiently protected to be suitable for subdivision.