Natural hazards
Abstract
New Zealanders are exposed to a wide variety of natural hazards that impact on people, property, infrastructure and the wider environment. Human activities can exacerbate risks associated with hazards such as increase the occurrence or the severity of effects. With the effects of climate change likely to change the magnitude of some hazards, it is ever more important for those managing and planning for natural hazards to improve systems and techniques for planning for and responding to, natural hazard risks. Planning for hazards can reduce the potential for injury, damage or loss of life or property.
This guidance note has been prepared for planners, but it is also aimed at helping to inform politicians, hazards analysts, emergency management officers, technical specialists, consultants and others involved in natural hazard management.
This guidance note is limited to RMA planning for natural hazards. However local authorities need to also consider hazards originating from human activity under their Civil Defence and Emergency Management (CDEM) responsibilities. This note provides guidance on:
- Natural hazard terms and risk management principles
- RMA techniques and tools for managing natural hazards
- Non-RMA techniques and tools for managing natural hazards
- Integrated approaches to hazard management
- Managing specific hazards through resource management plans
Additional information is also provided on:
Climate change is not dealt with as a hazard in itself but is recognised as an influence on the future frequency and severity of hazards such as flooding, drought, and erosion. Further information on climate change can be found in the Guidance Note on Planning for the Effects of Climate Change and on the Ministry for the Environment website under Climate Change Issues.
Guidance note
Introduction to natural hazards and risk management
Terms and definitions
Natural hazard management inNew Zealand is underpinned by a number of key concepts, terms and definitions. It is important to use the correct terms and definitions when referring to natural hazards.
Where possible, use terms and definitions from key legislation and ensure that there is consistency between policy documents in how hazards are referred to.
Policy documents should provide a definition of a 'natural hazard '. The term is defined in the RMA, CDEM Act and Building Act, however as these definitions differ, the one you use will depend on the purpose of the type of plan or strategy being developed and the legislation it was developed under.
Risk Standard AS/NZS Standard 4360 provides definitions for some of the key terms used in natural hazards management.
Adopting a 4 'R 's ' approach
The underlying philosophy of the CDEM Act is the '4 Rs' (Reduction, Readiness, Response, Recovery) to mitigate or avoid the impacts of hazards. Each 'R ' is relates to, and overlaps with, the others. For example, response leads into recovery; and reduction measures can be part of recovery activities. RMA planning generally (but not exclusively) falls under ‛reduction '. Reduction approaches the primary focus of this guidance note.
Roles and responsibilities for natural hazards management
No one agency is responsible for natural hazard management in New Zealand. Rather, natural hazard management responsibilities extend to a number of organisations including local authorities. (See the Roles and responsibilities for natural hazard management and the natural hazard management activities undertaken by regional and territorial authorities.)
The risk-based approach to planning for hazards
Principles for planning approaches
These guidelines are based on four overarching principles:
- Gathering
accurate natural hazard information: Identifying and
accurately locating hazards on planning maps is essential for communicating and
mitigating hazard risk. Collecting information often requires specialised
technical knowledge and surveys. Maps showing the location of hazards in the
vicinity of a property must be developed at an appropriate scale. As the
existence of a particular hazard may have a major effect on a decision to
purchase or build on a property, all information on hazards should be as
accurate as technology and resources permit.
- Planning to
avoid natural hazards before development and subdivision: Natural hazards can be avoided by
preventing building and development on known hazard areas. Where natural hazards
cannot be avoided, mitigation such as reducing risk through engineering works
should be instigated. For example, the developer of a new subdivision may be
required to avoid building on a landslide. Avoidance is the safest and most
satisfactory long-term solution for current and future landowners and for the
local authority. It can also be achieved for little or no extra cost (although
it is recognised that loss of development opportunities are a cost to the
developer). Alternatively, mitigation
measures may be implemented so that the risk is reduced to an acceptable
level.
- Taking a
risk-based approach in areas already developed or subdivided: If land has
been subdivided and sites have been purchased, there will very likely be an
expectation that building on these sites will be allowed. Planning for land use
in a hazard zone helps to avoid or mitigate the increased risks from natural
hazards caused by land-use intensification (such as urban infill) and
inappropriate building.
The 2004 Australian/New Zealand Risk Management Standard 4360: specifies the elements of the risk management process, but does not seek to enforce uniformity of risk management systems. Rather, the design and implementation of the risk management system for natural hazards is influenced by the specific nature of issues. The application of the approach can therefore vary and organisations should adapt it to suit their particular issues. For assessing natural hazards in a planning context, this standard has been modified. An example of this follows for landslides.
- Communicate risk of hazards in built-up areas: One of the
most difficult problems concerning natural hazards is dealing with urban areas
where buildings are constructed on, or close to, a particular hazard, such as an
active fault, floodway, or landslide. The ideal approach in this situation would
be to avoid further development in high-risk areas, to limit existing-use rights
to rebuilding (ie, replacement buildings can only be the same scale and density as those
existing), and to limit the use of buildings. Non-regulatory methods can
actively discourage people rebuilding and encourage them to move elsewhere.
The most realistic approach, however, is to accept the status quo whilst ensuring that:- any further development and use of buildings is consistent with the level of risk posed
- district plan maps
clearly show hazard zones.
One example of educating about a hazard is the landslide brochure Hutt City Council distributed to all hillside residents on managing the risk of landslides.
The principles recognise that a different planning approach is needed for an area that has not been developed than for an area that has been developed or subdivided (or where there is an expectation to build). These principles are underpinned by a risk-based approach.
Key concepts underpinning the risk-based approach (tools for risk identification, analysis, and evaluation) are summarised below. The remainder of the guidance note focuses on ways to manage or treat natural hazard risks (including the RMA tools to manage specific hazards).
More detailed information on how to adopt a risk-based approach to natural hazards is contained in the Companion Guide to Risk Standard AS/NZS Standard 4360.
(1) Identification of risks
Identifying the 'hazardscape ' is an important step to understanding the risks posed to communities by natural hazards. For those planning under the RMA, identifying the likely risks facing a district, city, or region is the first part in establishing whether issues, objectives, policies or rules needed to be included for them in RMA plans. For those working on resource consents, checking for the presence of natural hazards is important in both preparing and considering assessments of environmental effects in accordance with Schedule 4 (clause 2(f)).
A starting point to identify hazards risks is a scan of hazard information, including recent hazard events (such as floods and slips) for the area. It is good practice for councils to map known hazards in their areas to help with plan preparation, and enable those processing consents to quickly understand the hazards that may impact on a proposal, or that may be exacerbated by a proposed activity or development.
The National Hazardscape Report provides a definitive snapshot of the latest knowledge on New Zealand 's hazards and risks.
In identifying risks through hazard mapping councils should:
- adopt an all-inclusive approach to hazard mapping recommended, starting with the regional setting, then focusing in to the detailed scale
- consider appropriate
scales for hazard mapping to ensure information is portrayed accurately and not
misrepresented. Suggest scales are:
- National (1:1,000,000)
- Regional (1:100,000 to 1:500,000) - QMAP series
- Medium (1:25,000 to 1:50,000) - typically municipal or small metropolitan areas
- Large (1:5,000 to 1:15,000) - typically site or property level. This scale is recommended for district plan hazard mapping.
- map hazards at a scale that is appropriate to the end-use purpose (the end-use maps, for example those used in district plans, should not be significantly different to the scale the hazard was originally mapped at to avoid errors or misrepresentation of the information contain in the maps)
- consider of scale when combining hazard maps with other types of maps
- ensure that hazard mapping information is not distorted when using GIS by limiting the use of the zoom tool on GIS systems beyond the scale the original hazard was mapped at
- be mindful that hazard information available to the public should have disclaimers regarding the mapping and information contained in such maps.
The use of aerial photography
Aerial photography is useful for identifying various hazards, such as active faults and landslides. Comparing aerial photographs of an area over time can give an indication of the frequency and extent of various events. Different types of photography, including vertical (or oblique) aerial photos and orthophotos), provide different hazards information.
It is important to use photographs from different periods spanning as much time as possible, as land development can often conceal the presence of features (for example, earthworks can modify an environment so that the original features, such as fault lines and landslides, are 'removed ' from the site).
Identify natural hazard risk level
As part of risk identification ask questions about each of the key activities, projects or processes.
Good quality information is important in identifying risks. The starting point for risk identification is historical information and discussions with a wide range of stakeholders about historical, current and evolving issues. People involved in identifying risks are knowledgeable about the detailed aspects of the risk identification being undertaken. Identifying risks can also require imaginative thinking and appropriate experience. Allow for the pooling of experience. Team involvement helps build commitment and ownership into the risk management process and helps ensure that risks to different stakeholders are considered where appropriate.
In order to understand the risk a hazard may pose, start by establishing the hazardscape (from hazard identification studies), location, social environment, economic environment, etc). Alternative information sources can be used in the absence of detailed hazard studies. Alternative sources of information could include:
- historical photographs and paintings of events
- first hand accounts of events
- information held by local libraries
- information collected for other purposes such as university research
- information collected by old catchment boards
- historical records for organisations such as the ministry of works and development.
Once the hazardscape has been defined, the hazard risks posed by different activities, processes or projects in a particular area can then be identified.
(2) Risk analysis
Having established the hazards that may be applicable to a given area, district or region the next step is to determine the significance of hazard risk. A risk analysis is often required to:
- obtain more information about the consequences or the likelihood of decisions about priorities being based on information and data rather than guesswork.
- better understand the risk and its causes so that treatment plans can be directed at true rather than superficial causes of problems.
- help people choose between options where each has different costs and benefits and potential opportunities and threats.
- provide a better understanding of risk to individuals who must operate with the risks.
- provide an understanding of residual risk after treatment strategies have been applied.
Risks that are considered to be high or significant may require further evaluation and possible treatment (actions to avoid, remedy or mitigate them). Conversely, for some hazards the risk level may be low so as to not require immediate, or further, consideration.
Risk analysis establishes an understanding of the level of risk and its nature. Aside from the absolute level of risk, analysis will help to set treatment priorities and options. The level of risk is determined by combining consequence (potential impact) and likelihood (probability).
Risk analysis can be performed either qualitatively (using words to describe the magnitude of potential consequences and the likelihood that those consequences will occur), quantitatively (uses numerical values for both consequences and likelihood) or a combination of both. Suitable scales and methods for combining consequence and likelihood should be consistent with the criteria defined when establishing the context. For more technical analysis, the nature of the data and required output will dictate the required analysis methods.
Decisions as to which risk analysis method should be used are influenced by the context, objectives of the risk analysis and available resources. Some risks may need to be examined in detail and a risk analysis may be undertaken to varying degrees of detail depending upon the risk, purpose, and the information, data and resources available.
The order of complexity and costs of analyses, in ascending order, is qualitative, semi-quantitative and quantitative. In practice, qualitative analysis is often used first to obtain a general indication of the level of risk and to reveal the major risk issues. It can be used as a way of screening overall hazard risks and assigning priority for those that need further evaluation. Later it may be necessary to undertake more specific, quantitative, analysis on the major risk issues.
Outputs of risk assessments can include susceptibility maps and matrices. For example, susceptibility maps for landslips or slumping can rank slope stability of an area into categories that range from stable to unstable. A susceptibility map can show where landslides may form. Wellington has some good examples of landslide susceptibility maps.
Sensitivity analysis
Since some of the estimates made in risk analysis are imprecise, a sensitivity analysis should be carried out to test the effect of uncertainty in assumptions and data. A sensitivity analysis is also a way of testing the appropriateness and effectiveness of potential controls and risk treatment options. Consider engaging someone experienced in undertaking sensitivity analysis to undertake this task.
The example of a sensitivity analysis below shows bars of uncertainty for the tsunami risk in Gisborne. The dashed lines show the uncertainty at the 16th and 84th percentiles. The tsunami risk for each of the main centres was presented with these uncertainty bars in the Review of Tsunami Hazard and Risk in New Zealand (see the Ministry of Civil Defence and Emergency Management website).

Sensitivity analysis for tsunami in Gisborne
This diagram shows wave height on the y-axis and the tsunami return period on the x-axis.
(3) Risk evaluation
Having established the presence of a natural hazard, and an approximation as to the level of risk associated with that hazard, the third step is to evaluate options in regard to managing risk (including the 'do nothing option '). This stage of the process helps inform s.32 reporting, plan objectives and policies, or may form part of the process in considering whether avoidance or mitigation options proposed in a resource consent application are appropriate.
Evaluating options involves weighing the relative costs of each option with the losses that will occur if the risk is not treated. The costs and losses to all parties should be considered, noting also that who benefits and who pays may vary across options. Some costs may be indirect, for example loss of business opportunities during an event. Any losses realised or, alternatively, benefits gained from avoiding or reducing them, may only accrue over time. As such, the likely costs and benefits arising over the full 'lifetime ' of each option should be analysed in Net Present Value terms.
For those preparing plans and strategies, determining acceptable levels of risk and willingness to pay for risk reduction across a community will require effective communication and consultation processes. These processes begin with determining the communities ' goals for hazard risk reduction and end with evaluating outcomes.
Decisions should take account of the wider context of the risk and include consideration of how tolerable the risks are to various parties who receive no benefit from them. In some circumstances, the risk evaluation may lead to a decision to undertake further analysis.
Risk prioritisation
A range of methods are available to prioritise risks. Generally, councils have used the SMUG and SMG analysis (a variation of the SMUG model) for prioritising hazards in their CDEM Group plans, based on the Risk Management Standard AS/NZ 4360. There are also some other variations being used.
The SMUG system is used to compare and prioritise hazards based on the Seriousness, Manageability, Urgency and Growth (SMUG) characteristics of each hazard. SMUG can also be used as a method of qualitative risk calculation.
The Nelson Tasman Civil Defence and Emergency Management Group plan uses a SMUG analysis.
Ideally, if undertaking a risk prioritisation process, councils should check what methods are contained in their CDEM Plan and adopt the same methodology where practicable. This will make it easier to ensure that the key priorities are the same under both CDEM and RMA processes (while recognising that a CDEM Plan is going to be wider than just natural hazards).
Residual risk
Residual risk is the risk that remains after all treatment steps are in place, in other words the fatalities, injuries and destruction that must be accepted either by default or because the costs of treatment are considered too high, and/or such outcomes are too uncertain or rare to plan for.
An assessment will not always reflect hazards influenced by extreme uncertainties. For example, uncertainties for flooding may include blockages, reduced channel capacities, channel infilling and debris flows. This along, with other uncertainties, creates the need for the residual risk to be defined and considered.
Not all study areas have the same uncertainties or residual risk, so this must be calculated and considered on a case-by-case basis.
Integrated approaches to hazard risk management
Managing common hazards over council boundaries
Natural hazards differ from area to area but rarely cease at local authority boundaries. Local authorities with overlapping hazard issues can work collaboratively to manage hazards in districts or a region/s and work together to identify who will:
- be the key information provider for natural hazards (and what should the information consist of)
- identify and map which hazards
- carry out education and communication campaigns
- be responsible for planning and responding to hazards (under the RMA as well as a CDEM response)
- develop and implement specific hazard mitigation plans for particular hazards.
These responsibilities can be formalised by agreements or memorandums of understanding between authorities on hazard management responsibilities and roles, or outlined in the regional policy statement. Triennial agreements under the LGA are tied into the RPS preparation process by Clause 3A of RMA Schedule 1. They require a more collaborative process for the development of regional policy statements, and provide a possible means around which relationships can be built between regional councils and territorial authorities. The Wellington Regional Policy Statement sets out hazard roles and responsibilities within the Wellington region.
Wherever possible, local authorities should collaborate so that an area-based approach to hazard management can be taken. Examples of this area-based approach where regional and district councils have worked together to address flood risk are the SLUI (Sustainable Land Use Initiative)developed by Horizons Regional Council, and the Peninsula Project, undertaken by Environment Waikato and the Thames-Coromandel District Council. Note that while this guidance note considers the response to hazards, collaboration may include a coordinated response across more than just the RMA, particularly for territorial authorities.
Other techniques that can assist integration include:
- pooling resources between councils (for example Environment Waikato and Environment Bay of Plenty combining work on tsunami risk, or the Hawke's Bay Regional and Hastings District Councils jointly undertaking studies to assess and quantify the extent of existing coastal hazards)
- adopting and formalising agreements as to responsibilities (for example the Joint Flood Risk Management Strategy prepared by the Otago Regional Council and Queenstown Lakes District Council).
Addressing multiple, inter-related hazards
It is important to look at the wider implications of hazards. Hazards that are interrelated (for example, an earthquake can trigger a landslide, which in turn could block a river leading to flooding) need to be recognised in the planning process. This is particularly relevant for natural hazards exacerbated by climate change.
Overlaying various hazard information within GIS or similar systems can be used to identify and address multiple risks in specific locations.
Treating risks: an overview of 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, however there are several areas of work underway at the national level that could inform such projects.
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 (see: writing provisions for plans guidance note for example).
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.
As provided for in sections 30 and 62 of the RMA, regional policy statements can be used to:
- pooling resources between councils (for example Environment Waikato and Environment Bay of Plenty combining work on tsunami risk, or the Hawke's Bay Regional and Hastings District Councils jointly undertaking studies to assess and quantify the extent of existing coastal hazards)
- adopting and formalising agreements as to responsibilities (for example the Joint Flood Risk Management Strategy prepared by the Otago Regional Council and Queenstown Lakes District Council).
To ensure integration with other hazard management activities in a region, the preparation of hazards provisions in a regional policy should be linked with work being undertaken, and priorities established, as part of the CDEM Group Plan (the Horizons 'One Plan' drafting process is an example of where the regional policy statements, regional plans and CDEM Group Plans have been integrated). (See the Guidance Note on the Plan Development Process.)
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 s.10 of the RMA (see s.10(4)). 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.
Chapter 9 of the Regional Coastal Plan for the Canterbury Region (2005) contains provisions relating to coastal hazards.
The Regional Water and Soil Plan for Northland contains provisions relating to flooding (see Section 11 of the Regional Water and Soil Plan for Northland).
Chapter 4 of the West Coast Proposed Regional Land and Riverbed Management Plan contains provisions relating to land stability.
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 regional policy statements. As such 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. The Timaru District Plan and the Western Bay of Plenty District Plan are amongst those that include specific chapters dealing with 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. The Wellington City District Plan maps identify 'Hazard (Faultline) ' and 'Hazard (Ground Shaking) Area ' overlays within the city. The district plan contains specific rules for activities in these areas. The Proposed Wanganui District Plan identifies a coastal hazard overlay zone for Kai Iwi Beach and, depending on the risk area in which the activity is located, rules apply to activities in the zone. 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 (for more information regarding how to write plan provisions, see the guidance note Writing Provisions for Regional and District Plans.
The Kapiti District Council uses a checklist for application for subdivision to help with such tasks. The key is to ensure that the natural hazard risk can be properly addressed when assessing a resource consent application.
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).
The Ngāti Tūwharetoa Environmental Iwi Management Plan contains statements on natural hazards.
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 (AEE). 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, or to, 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. For example, the Nelson City Resource Management Plan includes assessment criteria for activities located within the Tahunanui Slump Core and Fringe Overlay area.
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. The discussion paper on dealing with cumulative effects under the RMA provides more information on ways in which cumulative effects can be dealt with through plans and resource consents.
Local authorities can refuse consent for subdivision where the land is subject to certain hazards under section 106 of the RMA.
For further, general, guidance on the consent process, see the Consent Processing Resource.
Managing specific hazards through RMA plans
Introduction
The following section sets out how specific hazards can be managed through RMA plans.
The primary natural hazards in New Zealand are:
- earthquake/seismic
- landslip / landslide / land instability / subsidence
- coastal
- flooding
- geothermal
- meteorological
- tsunami
- volcanic.
Generally, resource management plans can contain objectives, policies and rules to manage:
- the effects of hazards themselves (such as coastal erosion)
- the effects of land use on hazard risk (such as the removal of dune vegetation)
- the effects of treating hazard risk (such as the loss of coastal access following the construction of a seawall).
The management response for specific natural hazards is highly dependent on the nature, location and effects of the particular hazard, and the community in which the hazard is located. No one policy response to natural hazards can address all hazards or all locations. Natural hazards policy should consider adapting the 'best fit ' hazard response to the nature of the particular hazard relative to its location recognising that the methods (or mix of methods) used to address the risk will often be different.
Many local authorities take an ‛all-hazards ' approach to developing hazard-related objectives and policies in their plans. This provides simplicity and may be acceptable for an overall hazard objective and some policies. However, a hazard-specific approach is likely to be more effective and easier to implement and monitor as the guidance it provides to those making decisions on, or monitoring, resource consents is more likely to be stronger, clearer, and more targeted towards the issues that need to be dealt with.
Plan provisions should focus on the effects that need to be addressed to achieve natural hazard objectives, and state how those effects are going to be dealt with. Plan provisions should also provide for a review of current policy where increased knowledge of a hazard becomes available.
Earthquake/seismic
New Zealand has earthquake hazards that can impact on the built environment in a number of ways including, shaking, liquefaction and mass movement.
A fault is a fracture in the Earth's crust. Opposite sides of the fracture are held together by pressure and friction, but as stress builds up a fault may suddenly rupture. In a large ruptures, shock waves cause the earth to shake violently and produce an earthquake. An active fault is a fault that has ruptured repeatedly in the past, and whose history indicates that it is likely to rupture again. An active fault therefore creates a fault hazard risk.
When the ground shakes, and/or when there is surface movement on a fault line causing ground deformation, there is likely to be damage and/or destruction of structures built across the fault line or within the crush zone. Earthquakes may also trigger other hazards, such as liquefaction, tsunami, landslides, and flooding.
Councils can plan for active faults through the identification of active faults on planning maps, with specific rules that limit development in higher risk areas.
Councils should provide specific objectives, policies and rules to address fault hazard risks for known active faults. Approaches to address fault hazard risks through plans could include one or more of the following:
- mapping active faults and using buffer zones to exclude development, or to restrict the type of development that occurs within the buffer zone
- requiring that structures, infrastructure or other development or activities in the vicinity of active faults are designed in such a way that minimises risk to life and property
- using non-regulatory methods such as the provision of information and advice, to raise public awareness and to encourage good practices.
For more detail, the Institute of Geological and Nuclear Sciences Active Fault Guidelines (http://www.mfe.govt.nz/publications/rma/planning-development-active-faults-dec04/index.html) provide specific guidance on how the earthquake hazard can be managed through planning documents and the mapping of active faults
The guidelines set out how councils can:
- actively identify and assess the actual and potential effects of the natural hazards associated with landslides/land instability/subsidence
- develop methods to reduce the risk associated with such events
- develop methods to avoid activities in areas prone to these hazards.
The Matamata-Piako District Plan contains an objective specifically addressing the risk of earthquakes in the district. The City of Lower Hutt District Plan includes policies to manage the Wellington Fault Special Study Area and requires suitable engineering and emergency management measures for ground-shaking hazard.
Wellington City and Kapiti Coast District Councils provide good examples of how councils have investigated fault hazard risks and introduced policy responses to address the issues (see WCC and KCDC case studies). The Wellington City District Plan has an extensive suite of rules dealing with fault hazard risk (including active faults and liquefaction zones). The plan combines plan overlays and rules restricting development in known fault hazard areas.
Landslip/landslide/land instability/subsidence
Land instability includes landslides, subsidence, and issues around alluvial fans. There are many types of landslides, including earth flows, topples, debris flows, rock falls, block slides, debris avalanches, lateral spreads, and rotational and translational landslides. The most common trigger of landslides is prolonged or intense rainfall; however large earthquakes, volcanic eruptions and geothermal activity can also trigger landslides.
Land instability can result in threats to life, property, and infrastructure. In hilly or mountainous areas with limited access, landslides and landslips can isolate communities and have disruptive side effects such as clogging water treatment facilities with silt.
The general approach taken in plans to landslides, land instability or subsidence is to reduce the risk and avoid activities in areas prone to these hazards. RMA plan provisions (typically district plans) can manage the hazard risk through:
- the identification and mapping of areas of land instability
- zoning to avoid development in areas subject to the hazards
- requiring site investigations and/or possible engineering works to assess and reduce risk in areas of identified land instability where avoidance is impractical or not warranted
- developing rules and standards to assess consents for activities in areas prone to these hazards.
Where risks are identified in policy statements and plans, councils should adopt a precautionary approach to development.
Guidelines on land instability for RMA consent and policy planners have been published that detail how a risk-based approach can be taken to planning for land instability risk, plan methods that could be employed, and mapping of land instability risk.
The Tauranga City Plan includes specific objectives, policies and methods to address land instability. Nelson City Council has developed the Tahunanui Slump Core and Fringe Overlay to control development in an area of known land instability.
Coastal hazards
Coastal hazards include storm surge, coastal erosion, sea-level rise, coastal flooding, and tsunami. These are all natural processes that become a hazard where they pose a threat to property and life.
Coastal hazards are generally well recognised in existing RMA plans with provisions aimed at managing coastal erosion and the inundation of land from coastal flooding, storms and sea-level rise.
There are a number of specific responses for managing coastal hazards through resource management plans, including:
- mapping where coastal erosion will occur in the future (hazard zones)
- setting back buildings an appropriate distance from the shoreline to minimise risk from erosion (building setbacks)
- placing only appropriate structures (for example, relocatable buildings) not key facilities in areas of known risk
- restoring sand dunes and vegetation which provide protection from the sea via a buffer zone
- removing structures from areas of risk via a programme of managed retreat
- installing engineered protection in the form of appropriate seawalls and rock walls
- beach nourishment (introducing extra sand to a beach system)
- doing nothing and letting the sea dictate.
Plans may identify and map areas that are subject to coastal hazards and include objectives, policies and methods, and standards that look to:
- reduce the risk of coastal hazards (such as through directing sensitive developments away from hazard prone areas)
- manage effects of, or effects of development on, hazards
- provide buffer areas between development and areas of high hazard risk
- identify engineering solutions
- control activities by consent activity status and using standards.
In areas subject to existing or new development, councils should consider both structural and non-structural options to managing coastal hazards. Coastal plans should provide guidance when considering which option is appropriate. The Auckland Regional Council has developed a Coastal Erosion Management Manual which includes guidance on determining whether hard or soft engineering options are appropriate for a specific location.
There is on-going debate about the best methods for determining the positioning of hazard zones and setback zones. As there is no one fit-all approach for coastal areas, councils need to determine the appropriate hazard and setback zones for their particular section of the coast. The Canterbury Regional Coastal Environment Plan provides a comprehensive set of provisions relating to coastal hazards based on the identification of hazard zones. The plan also provides a useful summary of the relevant approaches to managing coastal hazards at the start of the coastal hazards chapter.
A methodology for identifying hazard zones and setbacks should take into account the physical characteristics of a location, the quality of information available regarding the particular hazard, and the resources and expertise available. The hazard zone should be able to be easily understood by the community. The Wairoa Coastal Strategy provides an example of how councils can recognise both statutory and non-statutory approaches to managing the coastal hazard risk.
Details on how to incorporate climate change effects and sea-level rise into planning for coastal hazards can be found in the Ministry for the Environment publication Coastal hazards and climate change: a guidance manual for local government in New Zealand.
Flooding
Flooding in this context is defined as the inundation of land by water. Coastal flooding is addressed in the coastal hazards section.
The magnitude of the flood risk is dependent on the probability of a flood occurring, the value and type of assets or resources exposed to the risk, and the vulnerability of those assets or resources to damage.
The effects of flooding include the movement of debris, the build up of debris against structures, silt and/or mud deposition, erosion, and water damage to buildings and vehicles. Consequential contamination and health effects may arise from overloaded sewerage systems or transportation of hazardous substances.
Flooding can be caused by a range of factors and circumstances including:
- high, or particularly intense, periods of rainfall
- snowmelt (which may also coincide with high rainfall)
- blocked waterways or drainage systems (including natural damming after landslips or earthquake, or vegetation blocking drains, creeks or streams).
Human activity can also contribute to, or exacerbate, flood hazards by, for example:
- obstructing natural overland flow paths (such as by placing buildings, raised roadways, embankments and other similar obstacles in the flow path or flood channel)
- increasing the flow of water into natural or man-made drainage systems (removing vegetation, increasing areas of impermeable surfaces, or increasing the number of stormwater outlets, and thereby the amount of stormwater, that enters a particular drainage system).
There are many ways to mitigate the flood risk, but generally they fall into two groups:
- structural works: designed to contain floods and to limit erosion and deposition by controlling river behaviour
- non-structural methods: including land-use planning, emergency management planning, and flood-proofing of buildings. These methods are designed to either remove people and assets from risk or to manage exposure to flood effects.
In the main, RMA plans primarily address non-structural methods; however it is important that those preparing plans are mindful of structural works, and the possible need to accommodate them when drafting plans. Plan provisions may need to consider such matters as the placement, building, maintenance, operation and protection of structures such as stopbanks, weirs, groynes, flood gates, diversions, or other flood protection measures when writing objectives, policies and rules. District councils may also find that they have designations or notices of requirement for such structures that need to be included in their plans.
The potential tools available for land-use planning to manage flood risks through RMA plans are outlined below. As a general rule, the level of control imposed through plans should be commensurate with the potential flood risk.
| Tool | Use and links to RMA plans | Level of control imposed |
|---|---|---|
Identifying flood hazard through mapping and description of issues and scenarios. Example: the Invercargill City District Plan |
Generally used as an information tool that informs RMA plan provisions. It can either be part of a plan rule, or may dictate when plan provisions for managing flood risk apply. In other guises, it can be used to inform PIMs and LIMs. |
Low when used as an information tool only. High when linked to plan rules. |
Plan provisions that direct sensitive development away from areas of high flood risk (areas that experience frequent flooding and where there is a high potential for damage due to water level or water velocity) Example: the Palmerston North District Plan |
Zoning land for less vulnerable land uses, such as 'open space recreational use ', conservation, or hazard management. Such zoning may be linked to areas identified as being at most risk in mapping and scenarios. Provisions will generally exclude land uses such as commercial, residential, or industrial uses. |
High |
Rules that restrict the type of development that may occur |
Often associated with hazard overlays linked to particular plan objectives, policies and rules. These work in a similar way to zoning, but do not replace the underlying zone. Plan rules restrict the type of development allowed to occur to those that are less vulnerable to flooding (eg, grazing or recreational activities). Rules may also be written specifically to exclude activities that may obstruct flow paths (such as raised road embankments, concrete block walls, buildings, raised spectator facilities for sports grounds, or other barriers). Some regional plans also contain provisions relating to management of vegetation and structures in waterways that would otherwise clog or diminish the ability of a waterway to drain in a flood event. |
Moderate to high |
Development standards for activities located in flood prone areas. Example: the Thames Coromandel District Plan |
Activities located in areas identified by zoning, overlays or other hazard mapping may be required to comply with objectives, policies and rules specifying:
|
Low to moderate |
Plan provisions concerning the establishment, operation, maintenance and protection of flood protection works. |
Regional plan rules or consent conditions that:
|
Moderate to high |
Note that for district plans there are limitations in how effective land-use restrictions may be if existing use rights apply.
The Regional Water and Soil Plan for Northland provides a good illustration of the various tools and methods available to assist in planning for flood risk and activities on flood plains.
Kapiti Coast District Council controls development in some river corridors to avoid exacerbating the effects of flooding. The Kapiti Coast District Plan manages flood risk in the Otaki and Waikanae floodplains by identifying the estimated 1 percent annual exceedance probability (AEP) flood event, hazard categories and descriptions, and specific zone controls.
Councils should incorporate new flood risk-information into resource management plans as it comes to hand. Following a flood-risk study of the Coromandel Peninsula, the Thames-Coromandel District Council recently embarked on a process to strengthen the provisions in the district plan related to flood risk, including placing greater emphasis on avoiding flood hazard.
Geothermal
Geothermal activity is generally restricted to a few locations around New Zealand.
Geothermal hazards include scalding hot water, geyser eruptions, geothermal chemicals in water (including sulphur), boiling mud, steam and other gases, geothermally altered ground (prone to subsidence and landslides), landslide, and hydrothermal eruptions.
Geothermal hazards are natural in origin and can be induced by human activity such as large-scale geothermal extraction activities. They can result in:
- changes in surface geothermal activity, including hydrothermal eruptions
- subsidence
- increased microseismic activity
- effects on ecosystems, flora and fauna.
Regional and district plans should provide objectives, policies and methods for significant geothermal resources in their jurisdiction [if any]. Approaches to managing geothermal hazards include:
- scientific investigations to identify the scale, extent and nature of geothermal hazards, both when plans are developed or when consents are applied for in areas prone to geothermal hazards
- conditions on resource consents for geothermal extraction providing for specific monitoring of geothermal hazards. If monitoring establishes that there is a risk to life or property the resource consent should be reviewed under s.128
- ensuring development avoids areas of high geothermal hazard risk
- where limited information is available, adopting a precautionary principle approach towards planning for activities in areas of actual or likely geothermal hazard risk
- re-injection of geothermal water in order to limit subsidence and land instability in geothermal areas
- requiring the provision of assessment of the effects of development on geothermal hazard risk in resource consent applications through RMA planning documents.
The Rotorua Geothermal Regional Plan has been developed by Environment Bay of Plenty to address geothermal hazards in Rotorua. The Rotorua District Plan contains a formal assessment of effects that may occur on geothermal features as a result of subdivision and land development.
Local authorities should find a balance between the use of geothermal resources and protection from geothermal hazards in their policy responses. The Waikato Regional Plan Geothermal Variation provides a good practice example of how councils can recognise these often conflicting outcomes.
When preparing plans, plan changes or variations local authorities should consider including assessment criteria for applications to use and develop geothermal resources to address geothermal hazards. Clause 7.6.6.3 of the Geothermal Variation to the Waikato Regional Plan includes assessment criteria for activities in the vicinity of significant geothermal features.
Meteorological
Meteorological hazards include weather-related events such as:
- flooding
- drought
- sea-level rise
- extreme wind (including tornado)
- snow, frost, extreme temperature
- hail, lightning and fire (caused by lightening strike).
The effects of these hazards can be damage to infrastructure and property and the loss of life.
Modelling suggests climate change will increase the frequency and severity of such events to varying extents aroundNew Zealand . The Ministry for the Environment has produced a guide to assist local government in planning for the effects of climate change, Preparing for Climate Change – A Guide for Local Government in New Zealand.
Relatively few RMA plans currently contain provisions for meteorological hazards. In part this is largely due to the unpredictable nature of some of these events. However, a number of planning responses can be investigated for specific metrological hazards. Some aspects, such as building performance, are covered by the Building Code under the Building Act.
Issues and options that could be addressed through RMA plans could include:
- drought: the impact of drought is closely related to the availability and use of water. Objectives, policies, methods and rules in regional plans can be used to address the allocation of water resources (for example, under s.30(1)(fa)). District plans can include rules requiring water storage for new subdivision and development. See the Planning for Water Allocation Guidance Note
- wind: district plans can include a requirement to mitigate the effects of wind on, or exacerbated by, new development (for example, Rule 13.1.2.11 of the Wellington City District Plan requires that new buildings or structures above four storeys in height comply with specific standards)
- fire can be caused by lightning strike. District plans can include fire setbacks for residential areas. The proposed Rodney District Plan recognises the fire risk within the district and includes policies to address this risk.
Outside the RMA, the Building Code and various standards provide some options for dealing with meteorological hazard risks.
Snow loading for buildings and structures is specifically dealt within AS/NZS 1170.03 Snow Loads. The standard was issued in 2002 following a review of snow depth records in New Zealand .
The Building Act 2004 contains requirements for design to address issues associated with meteorological hazards. AS/NZS 1170 Structural Design Actions Set and 4203 General Structural Design and Design Loading for Buildings address earthquake forces, wind forces, snow loads, rainwater ponding loads, ice loads, soil loads and groundwater loads.
Tsunami
Tsunami are a series of large waves generated by sudden displacement of water (caused by earthquake, volcanic eruption or submarine landslide) capable of propagation over large distances and causing a destructive surge on reaching land. (The US National Oceanic and Atmospheric Organisation website has some useful material on tsunami).
Tsunami pose a risk to life, property and the environment by the inundation of water, which may also contain debris. Information on the risk to New Zealand and our level of preparedness is available via two reports (compiled by GNS Science) on the Ministry of Civil Defence and Emergency Management website.
To date, few plans have addressed tsunami risks beyond general provisions and taking a precautionary approach. Councils should provide more direction by planning for the tsunami hazard and the management of its effects. This can be achieved by mapping areas susceptible to tsunami hazard and taking a precautionary approach in areas vulnerable to effects from tsunami.
The publication 'Designing for Tsunami: Seven principles for planning and designing for tsunami hazards' provides some concepts and ideas relevant to second-generation RMA plans based on United States experience. Key ideas that may be useful in a New Zealand context include:
- identifying areas that may be at risk of tsunamis and incorporating this information into short and long-term planning decisions. Incorporating information on tsunami risks into hazard registers can be used to help evaluate consent applications for major developments in coastal areas
- acquiring, designating or zoning areas at high risk from tsunamis for public open space use
- avoiding new development in identified or likely tsunami run-up areas. Development that may be directed away from such areas could include: residential, commercial, and industrial uses (especially those involving hazardous materials), and critical facilities and systems (communication, emergency response, electrical power, water supply, and natural gas systems)
- in areas where it is not feasible to restrict land to open-space uses, using other land-use planning measures. These include strategically controlling the type of development and uses allowed in hazard areas, and avoiding high-value and high-occupancy uses to the greatest degree possible. This approach could for the basis of objectives, policies and rules in RMA plans
- considering site-specific mitigation measures aimed at slowing, blocking, or redirecting water, or raising structures above the area of expected inundation. Such considerations could form the basis of resource consent conditions.
Any land-use planning for tsunami needs to be integrated with a warning system and evacuation plan as, without these, many measures will not be effective. Good urban design can aid evacuation, such as the layout of roads and pathways (for example, ensuring there are roads that facilitate quick evacuation away from vulnerable areas by running perpendicular to areas such as beaches).
Volcanic
- lava flows
- ash fall
- gases
- lahars
- earthquakes
- debris avalanches (landslides)
- and pyroclastic flows.
These hazards are demonstrated in a diagram of volcanic features produced by the United States Geological Society. More information on the types and nature of volcanic hazards is available on the United States Geological Society website.
Pyroclastic flows can travel in excess of 15 kilometres from a volcano, and, depending on the wind, ash clouds can travel around the world from a single eruption.
Ashfall of 1 millimetre covers road markings, affects vehicle motors, water supply, wastewater, agriculture, horticulture, aircraft safety, electricity, buildings (for example, roof collapse) and communications. There are many areas inNew Zealand where volcanic activity is now dormant, but may reoccur in the future. A list of the effects to Auckland from an eruption is available on the Auckland Council website.
To date, plan provisions addressing volcanic events and the management of the effects of this natural hazard have been limited to engineering solutions, emergency management planning, monitoring, and specific volcanic contingency plans (for example, the Auckland Volcanic Plan and Waikato Volcanic Risk Mitigation Plan). These plans are predominantly reactive, emergency management operational plans rather than specific land-use plans. Within the Ruapehu district, the lahar hazard has been managed through the installation of lahar warning systems and structural mitigation works (channels, walls, and bridge reinforcing to channel the lahar). Network providers such as TranzRail have addressed the lahar risk to their infrastructure by reinforcing the rail bridge at Tangiwai against the impacts of lahars.
Councils should take a proactive approach to managing volcanic hazards through the inclusion of appropriate provisions in regional policy statements and plans (objectives, policies and methods) and encouraging good urban design. This could include:
- avoiding or restricting the location of facilities such as hospitals, schools, and other facilities that may be difficult to evacuate quickly in areas at risk from lahars, lava and pyroclastic flows, and debris avalanches
- requiring buildings in volcanic hazard areas to be designed and located in such a way that minimises risks (such as requiring strengthening of the roof and frame to withstand ash falls, or locating on higher ground away from likely mud or debris flow paths). These site- and activity-specific measures could be addressed through conditions on consents such as where design features to reduce risks from volcanic hazards are a matter of control or discretion. In Japan, buildings are designed to mitigate the effects of ashfall. This includes changes to roof design and stormwater collection from impervious surfaces
- designing safeguards for critical community networks (for example, water supply).
In Washington State (US) all counties are required to regulate land use and development within critical areas (for example, those defined as habitat and hazard). (See further details of this work.)
Best practice examples
Coastal hazard provisions
- The Proposed Wanganui District Plan identifies a coastal hazard overlay zone for Kai Iwi Beach.
- Chapter 17 of the Tauranga District Plan includes rules for coastal erosion or inundation hazard or flooding.
- Whakatane District Council has, as part of Coastal Hazards Variation 6, provided information on development scenarios into the Coastal Hazard Erosion Policy Area.
Flooding
- The Timaru District Plan contains objectives, policies and rules to avoid further non-essential development or redevelopment in the most flood-prone locations of the district.
- The Regional Water and Soil Plan for Northland contains provisions relating to flooding.
Integrated approaches
- Environment Waikato and Environment Bay of Plenty have combined their resources in developing research and plans for tsunami risk within their regions.
- Queenstown Lakes District Council (QLDC) and Otago Regional Council (ORC) prepared a Joint Flood Risk Management Strategy to address flood risk for the communities of Lakes Wakatipu and Wanaka. The joint strategy formalises the responsibilities and accountabilities of the two councils and the lake communities in regards to flooding in the district.
- The Wairarapa Coastal Strategy was developed by the Wairarapa Coastal Strategy Group (WCSG), which was a joint initiative between the Masterton, Carterton and South Wairarapa District Councils, Rangitaane o Wairarapa and Ngati Kahungunu o Wairarapa iwi, and Greater Wellington Regional Council. It provides a long-term vision for the Wairarapa coast. The Combined Wairarapa District Plan demonstrates how councils can pool resources and achieve integration across planning documents for their districts.
- The Hawke's Bay Regional and Hastings District Councils jointly undertook studies to assess and quantify the extent of existing coastal hazards as well as their impact on the coastal environment, along the coastline of the Hawke's Bay region. This work will allow the councils to develop rules for land uses that would exacerbate coastal erosion.
- Horizons 'One Plan ' drafting process is an example of where the RPS, regional plans and CDEM Group Plans have been integrated.
Land instability
- Nelson City Council has developed the Tahunanui Slump Core and Fringe Overlay to control development in an area of known land instability.
- The Tauranga City Plan includes specific objectives, policies and methods to address land instability.
Meteorological hazards
- Wellington City Council has prepared a wind design guide.
- Section 6.1.2 of the Auckland City Central Area Plan contains wind environment controls for buildings.
Legislative provisions
Resource Management Act 1991
The RMA provides for natural hazard management policy, planning and decision-making.
The key sections of the Act are:
Section 2 |
Interpretation |
Sections 30 |
Functions of regional councils |
Section 31 |
Functions of district councils |
Section 35 |
Duty to gather information, monitor, and keep records (especially s.35(5)(j) |
Sections 59-62 |
Regional policy statements |
Section 68 |
Regional rules |
Section 72-76 |
District plans |
Section 104 |
Consideration of resource consent applications |
Section 106 |
Consent authority may refuse subdivision consent in certain circumstances including where land is likely to be subject to erosion, subsidence and slippage |
Section 108 |
Conditions of resource consent |
Section 330-331 |
Emergency works (Guidance Note on Emergency Works) |
Other sections |
Part II, 58, 220, 229, 418, and 4th schedule. |
Civil Defence and Emergency Management Act 2002
The Civil Defence and Emergency Management Act 2002 aims at the comprehensive management of hazards and risks, and emergency response and recovery, through coordinated and integrated policy, response and recovery, and through coordinated and integrated policy, planning and decision-making processes at the national and local level. It sets out the duties, functions and powers of central government, local government, emergency services, lifeline utilities and the general public.
The Act is administered by the Ministry of Civil Defence and Emergency Management.
Building Act 2004
The Building Act 2004 provides for the regulation of building work, the licensing regime for building practitioners, and the setting of performance standards for buildings. It manages natural hazards in relation to the construction and modification of buildings.
Key sections of the Act are ss.35, 37 and 71-75.
Also relevant are the Building Regulations 1992 (including the Building Code) and Building (Specified Systems, Change the Use, Earthquake-Prone Buildings) Regulations 2005.
The Court discusses the relationship between the RMA and the Building Act in Bay of Plenty Regional Council v Western Bay of Plenty [2002] DC A27/02
Local Government Acts 1974 and 2002
The Local Government Acts 1974 and 2002 provide the general framework, obligations, restrictions and powers under which local authorities operate.
Key sections of the Act are ss.14, 93-97 and 163.
Local Government and Official Information and Meetings Act 1987
The Local Government and Official Information and Meetings Act provides for the public availability of official information held by local authorities, and to promote the open and public transaction of businesses at local authority meetings. Section 44A provides for land information memorandum and includes the matters which must be included in a LIM.
Other relevant legislation
- Environment Act 1986: sets out the function of the Parliamentary Commissioner (s.16) for the Environment and Ministry for the Environment (s.31), including obligations in the management of natural hazards (see s.17, s.32).
- Soil Conservation and Rivers Control Act 1941: makes provision for the conservation of soil resources, the prevention of damage by erosion and to make better provision for the protection of property from damage by floods.
- Land Drainage Act 1908: establishes drainage districts and boards and powers of local authorities relating to watercourses and drains.
- Forest and Rural Fires Act 1977: provides for the safeguarding of life and property related to fire in forests and rural areas.
- Earthquake Commission Act 1993: makes provision with respect to the insurance of residential property against damage caused by certain natural disasters.
Relevant case law
Natural hazards and sustainable management
Bay of Plenty Regional Council v Western Bay of Plenty District Council [2002] A27/02 andLowry Bay Residents Association v Eastern Bays Little Blue Penguin Foundation Inc [2001] W45/01 consider natural hazards under Part II of the RMA. These cases enforced the importance of considering the RMA 's purpose of sustainable management when making decisions on natural hazard management under the RMA.
RMA Section 106:
Henry v Kapiti Coast DC W024/03, 8 NZED 483 and Paviour v Napier CC W106/96 (PT), noted [1996] BRM Gazette 130 regarding the meaning of 'material damage ' in section 106 of the RMA. These cases establish that material damage implies something that is of great import.
Foreworld Developments Ltd v Napier CC [1998] W089/98 concerns an applicant's responsibility to propose measures to meet the requirements of s.106 and the consideration of other viable options before vesting land as reserve. In this case, the Court stated that the onus is on the applicant, rather than the council, to propose measures to satisfy s.106.
Maruia Soc Inc v Whakatane DC [1991] concerns the test used to determine if measures proposed by an applicant are sufficient to meet the requirements of s106. The test was applied in Resource Planning and Management Ltd v Marlborough DC [2003] CIV-2001-485-814.
Functions of regional and district councils
Canterbury RC v Banks Peninsula DC [1995] 3 NZLR 189 defined the meaning of 'avoidance ' or 'mitigation ' of natural hazards in s30 and s31 of the RMA. In this case, the Court outlined the limits on function of regional councils and territorial authorities and stated that neither a regional council nor territorial authority can make rules for purposes falling outside its functions. The Court also provided comment on the overlapping jurisdiction of regional councils and territorial authorities.
McKinlay v Timaru DC [2001] C024/01 contains discussion of what constitutes ‛exercising control of the use of land ' for the purposes of avoiding or mitigating natural hazards, under s.30 of the RMA. In this case, the Court stated that it is not enough for a regional council to only set out in a regional policy statement which authority shall take responsibility for developing objectives, policies and rules relating to the control of land for the avoidance of natural hazards, a regional council actually has to implement regional rules for this purpose.
RE: the Tauranga District Council [2003] A111/2003, a determination pertaining to the coordination of management between regional councils and territorial authorities. The Court acknowledged that the district council shares responsibility for natural hazard management with the regional council and the establishment of an integrated approach in terms of methods is essential.
Planning for natural hazards
Save the Bay v Canterbury Regional Council [2001] C6/2001, Bay of Plenty Regional Council v Western Bay of Plenty District Council [2002] A27/02 EnvC, and Skinner v Tauranga District Council [2002] A163/02 all provide discussion regarding the appropriate risk period to plan for when preparing regional and district planning documents. These cases point to a 100-year planning horizon for natural hazards.
Relationship between the RMA and the Building Act 2004
Bay of Plenty Regional Council v Western Bay of Plenty District Council [2002] A27/02 EnvC. The Court confirmed that it is appropriate for councils to consider the potential for a building to be affected by coastal hazards regardless of the fact that the design and construction of the building was considered under the Building Act.
Lowry Bay Residents Association v Eastern Bays Little Blue Penguin Foundation Inc [2001] W45/01. The Court outlined the different purpose of both Acts with the RMA promoting the sustainable management of resources and the Building Act focussing on the integrity and safety of buildings wherever they are located.
The Building Act 2004
Auckland CC v Logan [1999] AP77/99 looked as the meaning of ‛the land ' in the context of s.36(1)(a) of the Building Act. In this case, the Court concluded, ‛the land ' on which the building work was to be carried out did not have to refer to the entire site, but to the land that is intimately connected to the building works.
Existing use rights
McKinley v Timaru DC [2001] C24/2001 regarding the application of regional and district plan provisions to existing use rights. In this case, the Court commented that where regional rules governing the reconstruction of buildings do not exist then the property owner would have existing use rights to rebuild provided that the rebuilt dwelling was the same or similar in character, intensity, and scale as the present building.
See the Coastal Hazards and Climate Change Guidance Manual for further case law and discussion regarding climate change and coastal hazards.
Related guidance notes
Guidance on Consent Process: The Consent Processing Resource
State of the environment monitoring
Development of the policy framework
Monitoring and reporting one-stop-shop
Guidance on the plan development process
Enforcement Manual (Emergence Works)
Relevant publications
In the Quality Planning library
Natural Hazard Management - Research Report (Tonkin & Taylor for Ministry of the Environment, 2006)
National and international sources of information regarding the management of natural hazards. Contains an extensive bibliography.
Planning for Development of Land on or Close to Active Faults (GNS for Ministry of the Environment, 2004)
Provides guidance on land-use planning approaches for land that is on or near an active fault. (See also Planning for the Development of Land on or Close to Active Faults: A Study of the Use and Adoption of the Active Fault Guidelines (GNS, June 2005)
Guidelines for Assessing Planning Policy and Consent Requirements for Landslide Prone Land, (GNS Science, 2007)
This guideline can assist in determining if existing planning documents incorporate landslide and slope instability hazard appropriately.
Pre-event Recovery Planning for Land Use in New Zealand (GNS, June 2006)
Addresses the issue of recovery after a disaster, and presents a methodology for pre-event recovery planning for land-use inNew Zealand .
Preparing for Climate Change: A guide for Local Government in New Zealand (Ministry for the Environment, July 2004)
Assesses the likely effects of projected climate change during the 21st century and appropriate planning responses.
Coastal Hazards and Climate Change: A Guidance Manual for Local Government in New Zealand (Ministry for the Environment, May 2004)
A guidance manual to help local authorities manage coastal hazards.
Climate Change Effects and Impacts Assessment: A Guidance Manual for Local Government in New Zealand (Ministry for the Environment, May 2004)
Guidance on identifying and assessing likely future regional and local effects of climate change acrossNew Zealand .
Local Communities: Planning for Climate Change (Ministry for the Environment, May 2004)
Provides a general description of what causes climate change and identifies the likely impacts of climate change inNew Zealand .
Other publications
Ministry for the Environment publications on climate change website.
Critique of RMA natural hazard plan provisions in Review of the NZCPS (DOC, August 2006)
National Hazardscape Report: Development of a Natural Hazard and Risk Indicator Framework (Risk Strategies Research and Consulting for MCDEM October 2006)
National Hazardscape Report (ODESC, 2007)
Current challenges in practice
Integrated management of natural hazard information
Information management between and within councils presents challenges in its collation, storage and dissemination. Ideally, a centralised database or file should be complied to ensure that data is collected and stored in an integrated fashion. However, the use of this information can also present a challenge when the information on a file is incomplete, or has not been refined to the extent that it is able to withstand challenge. At present individual council systems for collection, storage and dissemination vary and there is no nationally accepted common practice.
Sharing information in a coordinated manner between councils also presents a challenge. Often regional councils may hold information at a scale that can be used by territorial authorities for resource consent applications, but the territorial authority is not aware of this information. Conversely, a territorial authority may have obtained useful information about hazards through its own plan development, monitoring, or resource consent processes that provide a high level of detail which could also benefit the regional council.
State of hazard knowledge
The state of knowledge for many hazards is relatively limited, such as for the tsunami risk. The costs associated with comprehensive studies for hazard risk make them not viable or a low priority for some councils. Consequently some areas in New Zealand have limited information for hazard risks that directly affected them.
In addition to the limited knowledge on some kinds of hazards, councils continue to struggle with processes to keep hazard information up to date on council systems.
Perceptions and acceptance of risk
A key difficulty in managing natural hazards is the public perception and acceptance of risk. Community awareness and education initiatives can increase a community 's knowledge of natural hazards, however the issue of residual risk is harder to communicate. There will always be some residual risk even if mitigation has been undertaken. There is often community reaction when an event occurs and mitigation is unsuccessful. Likewise, when an event occurs and mitigation is successful this can lead to a false sense of security
Implementation
Proactive rather that reactive planning for natural hazards remains difficult because relocating and restricting development is generally unpopular.
Due to the long return periods associated with natural hazard events, the monitoring of the effectiveness of natural hazard policy is difficult. Often the effectiveness of particular policy approaches cannot be tested until a hazard event occurs.
Existing use rights and property rights make it harder to encourage soft over hard engineering options within an at-risk area.
Existing use rights and district and regional plans
Existing use rights under section 10 of the RMA mean that a building can remain in an area subject to natural hazards (provided that there are no regional rules requiring otherwise) or, if damaged or destroyed by a natural hazard, it can be rebuilt (to a same, or similar character or scale), even once the risk has been realised. This means that district plan rules may have limited effect where development in hazard-prone areas already exists.
However, under section 10(4) of the RMA, existing use rights do not apply to regional council controls on land where such controls exist to avoid or mitigate natural hazards (s.30(1)(c)(iv)). The s.10(4) exception from existing use rights makes regional plan rules potentially more effective at dealing with existing development in hazard-prone areas than district plans.
Section 20A is also relevant where existing activities require resource consent as a result of a new regional rule. It allows for existing activities to be assessed against new provisions (for example, new hazard provisions) and potentially declined if the effects of the activity, in light of the new provisions, are too great. It is therefore important that district and regional councils coordinate their approaches to existing developments. The reconstruction of the Eichardts Hotel in Queenstown is an example of where a building was reconstructed following a major flood event. (See case law on existing use rights.)
Coordination across jurisdictions in the coastal environment
The coastal environment includes a demarcation of territorial and regional council responsibilities above and below mean high water springs (MHWS). RMA plans need to recognise that coastal hazards cross this jurisdictional boundary. One way to achieve this is by coastal plans recognising the contribution of the wider coastal environment (both landward and seaward areas) in the management of coastal hazards.
The Canterbury Regional Coastal Plan contains hazard controls for areas inland of the MHWS.
The Draft Hawke 's Bay Regional Coastal Environment Plan also defines a wider coastal environment including: the coastal marine area; tidal waters and foreshore above MHWS; dunes; beaches; coastal cliffs; and other areas where activities occur or may occur which have a direct physical connection with, or impact on, the coast.
Joint coastal strategies and plans can assist in achieving integration between the different roles and responsibilities within the coastal environment.
Acknowledgements
This guidance note was commissioned by the Ministry for the Environment and prepared by Lesley Hopkins of Beca Carter Holldings Ferner Ltd. with the support of Wendy Saunders (GNS Science).
The Ministry for the Environment also thanks the following people for their input and assistance in the preparation of the guidance note:
- Richard Hills and Stephen Swabey (Ministry for the Environment)
- Rian van Schalkwyk (Greater Wellington Regional Council)
- Greg Holland ( Auckland Regional Council)
- Peter Wood and Jonathan Jull (Ministry of Civil Defence and Emergency Management)
- Megan Collins (Environment Waikato)
- Helen Grant (Environment Canterbury)
This guidance note was completed in October 2008 and updated in November 2010 to reflect the RMAA 2009.
