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Proposed Kāpiti Coast District Plan

Natural Hazards

 

Kāpiti Coast District Plan Review Section 32 Analysis – Summary Report Natural Hazards


Proposed Kāpiti Coast District Plan

Natural Hazards

1 INTRODUCTION TO NATURAL HAZARDS Natural hazard means any atmospheric, earth or water related occurrence (including earthquake, tsunami, erosion, volcanic and geothermal activity, landslip, subsidence, sedimentation, wind, drought, fire and flooding) the action of which adversely affects or may adversely affect human life, property, or other aspects of the environment. The majority of the 46,000 people who live in the Kāpiti Coast District, live on a fairly flat coastal plain that extends along the western margin of the Tararua Ranges. Much of this coastal plain is only marginally above the existing sea level and is split at various points by a series of relatively swift flowing streams and rivers with steep catchments, all of which present varying levels of flood risk to the settlements which have grown up around them. Flooding is the most frequent natural hazard in the District. The Council has adopted a precautionary and risk based approach to hazard management. The approach includes avoiding new development in areas subject to high risk from hazards and mitigating effects in areas subject to lower risk or where the hazard has a long return period. The approach takes into account the effects of climate change and considers relocation of existing development subject to hazards worsened by climate change effects.

1.1 Description of Natural Hazards Natural hazards are the threat of naturally occurring events that may have a negative effect on people or the environment. In addition to the seismic hazards, the big global issue related to natural hazards is the impact of climate change. Over the coming decades we face increased risk of flooding and erosion caused by more intense storms and a likely rise in sea levels from a combination of melting ice and the expansion of warmer water. Coastal communities like Kāpiti are more vulnerable than most. Public and private development must be undertaken in a manner which lessens the adverse effects of natural hazards. The most appropriate approach is a precautionary one. In reality this requires avoiding new development in areas subject to high risk from hazards if the risk can not be mitigated. Development is more appropriate in areas subject to lower risk or where the hazard has a low probability or long recurrence interval. The Operative District Plan originally did not address the issues climate change as this was not recognised as a significant issue as the time the operative plan was developed. However subsequent flood modelling undertaken in 2004, took projected climate change into account. It is important to note that the climate change scenarios which were considered in 2004 are now outdated and climate change impacts are projected to be far more severe.

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Natural Hazards

The approach of the Natural Hazards chapter is to take into account the effects of climate change and consider relocation of existing development that is susceptible to hazards worsened by climate change.

1.2 Summary of Natural Hazards Issues The Council faces a number of challenges in relation to the management of Natural Hazards. These are outlined in Chapter 9 of the proposed District Plan, but are summarised as follows:        

 

The potentially adverse effects of natural hazards on the environment including loss of life and property damage. The potential worsening of the risks or severity of natural hazards that can result from inappropriate use and development of land. The threat to existing and future communities from natural hazards, the potential and nature of which may be unknown. Recognition and understanding of the range of existing natural hazard threats and the likely frequency and magnitude of particular events. Identification of areas of high hazard risk, especially those prone to erosion, flooding and land instability. Incorporation of comprehensive systems of hazard identification and analysis into the resource consent and building consent processes. Damage to natural systems through inappropriate hazard protection measures. The contribution which certain land use activities have in increasing the hazard threat especially in high-risk areas. Such activities include clearance of vegetation, earthworks in sensitive foreshore and riparian areas, erection of structures especially buildings in flood plains. Maintenance of existing protection works, including flood control schemes, and effectiveness of future works. Recognition of global warming and the effects of rising sea levels on future land use and subdivision activities along the coast.

Coastal Hazards Approximately 25km of the 40km of coastline has urban development directly adjacent to the coastal edge. This increases the risk to the community with such a large proportion of urban development in close proximity to the coast. Flood Hazards The District’s physical landscape presents varying levels of flood risk to settlements (particularly on the coastal plain). During high rainfall events flooding can occur within minutes of the event and can result in significant damage. Earthquake Hazards The District is subject to most earthquake hazards including strong ground shaking, liquefaction, fault rupture and earthquake induced slope failure. Five active fault traces have been identified within the District Plan.

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Natural Hazards

Tsunami is acknowledged as a natural hazard for the District given the exposure to the coast. Erosion and slope stability Landslips pose a significant risk to not only existing properties within the district but also to significant infrastructure such as State Highway 1 and the rail corridor. In the southern and south-eastern parts of the district the terrain is steep and slopes have a very high susceptibility to slope failure. Fire Hazards The district has a high fire danger. The nature of the Kāpiti Coast climate varies greatly, resulting in the District developing a high fire danger, sometimes earlier than the rest of the Wellington Region.

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2 STATUTORY FRAMEWORK The Resource Management Act 1991 (“RMA” or “the Act”) requires that there be a District Plan in place at all times for the Kāpiti District. The purpose of preparing, implementing and administering a District Plan is to assist the Council to carry out its functions in order to achieve the purpose of the Act. The RMA sets out the manner in which the District Plan is to be amended and the particular considerations the Council must follow when undertaking such an exercise. This report has been prepared in accordance with section 32(5) of the Act. It represents a summary of the evaluation of alternatives, costs and benefits undertaken by the Council in respect to the proposed District Plan provisions relating to open space as required under s 32(1) of the Act. In particular section 32 states: (1)

In achieving the purpose of this Act, before a proposed plan, … is publicly notified … an evaluation must be carried out by— … (c) the local authority, for a policy statement or a plan... (2) A further evaluation must also be made by— (a) a local authority before making a decision under clause 10 or clause 29(4) of the Schedule 1; and … (3) An evaluation must examine— (a) the extent to which each objective is the most appropriate way to achieve the purpose of this Act; and… (b) whether, having regard to their efficiency and effectiveness, the policies, rules, or other methods are the most appropriate for achieving the objectives. 3A) This subsection applies to a rule that imposes a greater prohibition or restriction on an activity to which a national environmental standard applies than any prohibition or restriction in the standard. The evaluation of such a rule must examine whether the prohibition or restriction it imposes is justified in the circumstances of the region or district. (4) For the purposes of the examinations referred to in (3) and (3A), an evaluation must take into account— (a) the benefits and costs of policies, rules, or other methods; and (b) the risk of acting or not acting if there is uncertain or insufficient information about the subject matter of the policies, rules, or other methods. (5) The person required to carry out an evaluation under subsection (1) must prepare a report summarising the evaluation and giving reasons for that evaluation. (6) The report must be available for public inspection at the same time as the document to which the report relates is publicly notified ….

This report has been prepared in accordance with section 32(5) of the Act. It represents a summary of the evaluation of alternatives, costs and benefits undertaken by the Council in respect to the proposed District Plan provisions relating to the rural environment as required under s 32(1) of the Act. The report addresses the necessary considerations as follows:

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Report Section

Category

3

General Statutory Requirements

4

Evaluation of Proposed Objective

5

6

Natural Hazards

Evaluation of Proposed Policies

Evaluation of Proposed Rules and other Methods

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Specific Consideration (sub-section) 1.

Accordance with council functions under the Act;

2.

Accordance with National Policy Statements and New Zealand Coastal Policy Statement; Accordance with Wellington Regional Policy Statement; Accordance with Regional Plans; Accordance with other relevant Plans; Non-consideration of effects of trade competition

3. 4. 5. 6.

1. 2. 3.

The proposed objective Does the proposed objective achieve the Act’s purpose? the extent to which the proposed objective is the most appropriate way to achieve the Act’s purpose.

1. 2.

Do proposed policies achieve the relevant objectives? Do proposed rules and other methods implement the relevant policies? Are policies and rules and other methods most appropriate (given their efficiency & effectiveness) for achieving the relevant objectives, including:

3.

3.1 costs & benefits of proposed policies, rules and methods; & 3.2 risk of acting (or not acting) if information gaps exist about the subjects of the policies, rules or other methods? 4.

What are the actual and potential effects on the environment of activities, including, in particular, any adverse effect of proposed rules or other methods?

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3 GENERAL STATUTORY REQUIREMENTS 3.1

Council Functions

Section 31 of the RMA outlines the Council’s functions. Subsection 1(a) sets out the requirement for objectives, policies and methods to be established, implemented and reviewed to achieve the integrated management of effects of the use, development or protection of land and associated natural and physical resources of the District. The Council’s existing District Plan satisfied the ‘establishment’ requirement of this function, whilst the ‘implementation’ role is delivered through Council’s regulatory planning and enforcement channels. The third requirement is to ‘review’ the provisions of the District Plan, a task that is further reinforced by s79(1)(c) of the Act. The 2012 District Plan Review, a wider Council project of which this report forms part, has accordingly been designed to assist the Council in meeting both the s31(1)(a) and 79(1)(c) obligations. The review of the natural hazards provisions in the District Plan has also been designed to accord with subsection 31(1)(b), which requires the Council to control any actual or potential effects of the use, development, or protection of land, including for specific purposes. The review has had particular regard to the need to improve the Community’s resilience to the effects of natural hazards through the management of activities occurring in the District. Key provisions of the RMA in relation to managing natural hazards include: S6

Matters of National Importance: “…shall recognise and provide for the following matters of national importance...” (a) the preservation of the natural character of the coastal environment…, and lakes and rivers and their margins, and the protection of them from inappropriate subdivision, use and development

S7

Other Matters: “…shall have particular regard to…” (f) maintenance and enhancement of the quality of the environment (i) the effects of climate change

3.2

National Policy Statements & Coastal Policy Statement

The RMA requires1 that the District Plan give effect to any National Policy Statement (“NPS”). A NPS is a document prepared under the RMA to help local government decide how competing national benefits and local costs should be balanced 2 . Three National Policy Statements have been gazetted to date, being:   

NPS on Electricity Transmission (2008) NPS for Renewable Electricity Generation (2011) NPS for Freshwater Management (2011)

                                                              1 2

s75(3)(a) Reference: www.mfe.govt.nz/rma/central/nps (December 2011)

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All three NPS documents have been actively considered by the District Plan Review project. The New Zealand Coastal Policy Statement (“NZCPS”) has also been considered and given effect to. Its purpose is to state policies in order to achieve the purpose of the Act in relation to the coastal environment of New Zealand3 . The NZCPS is a particularly relevant document for the Kāpiti Coast District, where the overwhelming majority of the built environment lies within the Coastal Environment. Most of the relevant NZCPS objectives and policies are unique to coastal environments; however some of the District’s rural areas do lie within the coastal environment. Relevant objectives and policies to the management of natural hazards within the coastal environment include: Policy 3: Precautionary approach 2. a. b.

In particular, adopt a precautionary approach to use and management of coastal resources potentially vulnerable to effects from climate change, so that: avoidable social and economic loss and harm to communities does not occur; natural adjustments for coastal processes, natural defences, ecosystems, habitat and species are allowed to occur; and

Policy 4: Integration Provide for the integrated management of natural and physical resources in the coastal environment, and activities that affect the coastal environment. This requires: c. particular consideration of situations where: iii. development or land management practices may be affected by physical changes to the coastal environment or potential inundation from coastal hazards, including as a result of climate change; or Policy 7: Strategic planning 1. In preparing regional policy statements, and plans: a. consider where, how and when to provide for future residential, rural residential, settlement, urban development and other activities in the coastal environment at a regional and district level; and b identify areas of the coastal environment where particular activities and forms of subdivision, use, and development: i. are inappropriate; and ii. may be inappropriate without the consideration of effects through a resource consent application, notice of requirement for designation or Schedule 1 of the Resource Management Act process; and provide protection from inappropriate subdivision, use, and development in these areas through objectives, policies and rules. Policy 24: Identification of coastal hazards 1.Identify areas in the coastal environment that are potentially affected by coastal hazards (including tsunami), giving priority to the identification of areas at high risk of being affected. Hazard risks, over at least 100 years, are to be assessed having regard to: a. physical drivers and processes that cause coastal change including sea level rise;                                                               3

s56, RMA 

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b.

short-term and long-term natural dynamic fluctuations of erosion and accretion; c. geomorphological character; d. the potential for inundation of the coastal environment, taking into account potential sources, inundation pathways and overland extent; e. cumulative effects of sea level rise, storm surge and wave height under storm conditions; f. influences that humans have had or are having on the coast; g .the extent and permanence of built development; and h. the effects of climate change on: i. matters (a) to (g) above; ii. storm frequency, intensity and surges; and iii. coastal sediment dynamics; taking into account national guidance and the best available information on the likely effects of climate change on the region or district. Policy 25: Subdivision, use, and development in areas of coastal hazard risk In areas potentially affected by coastal hazards over at least the next 100 years: a. avoid increasing the risk of social, environmental and economic harm from coastal hazards; b. avoid redevelopment, or change in land use, that would increase the risk of adverse effects from coastal hazards; c. encourage redevelopment, or change in land use, where that would reduce the risk of adverse effects from coastal hazards, including managed retreat by relocation or removal of existing structures or their abandonment in extreme circumstances, and designing for relocatability or recoverability from hazard events; d. encourage the location of infrastructure away from areas of hazard risk where practicable; e. discourage hard protection structures and promote the use of alternatives to them, including natural defences; and f. consider the potential effects of tsunami and how to avoid or mitigate them. Policy 26: Natural defences against coastal hazards 1. Provide where appropriate for the protection, restoration or enhancement of natural defences that protect coastal land uses, or sites of significant biodiversity, cultural or historic heritage or geological value, from coastal hazards. 2. Recognise that such natural defences include beaches, estuaries, wetlands, intertidal areas, coastal vegetation, dunes and barrier islands. Policy 27: Strategies for protecting significant existing development from coastal hazard risk 1. In areas of significant existing development likely to be affected by coastal hazards, the range of options for reducing coastal hazard risk that should be assessed includes: a. promoting and identifying long-term sustainable risk reduction approaches including the relocation or removal of existing development or structures at risk; b .identifying the consequences of potential strategic options relative to the option of “do-nothing”; c. recognising that hard protection structures may be the only practical means to protect existing infrastructure of national or regional importance, to sustain the potential of built physical resources to meet the reasonably foreseeable needs of future generations; s32 Report – Natural Hazards  

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d. e. 2. a. b. c.

Natural Hazards

recognising and considering the environmental and social costs of permitting hard protection structures to protect private property; and identifying and planning for transition mechanisms and timeframes for moving to more sustainable approaches. In evaluating options under (1): focus on approaches to risk management that reduce the need for hard protection structures and similar engineering interventions; take into account the nature of the coastal hazard risk and how it might change over at least a 100-year timeframe, including the expected effects of climate change; and evaluate the likely costs and benefits of any proposed coastal hazard risk reduction options.

3.

Where hard protection structures are considered to be necessary, ensure that the form and location of any structures are designed to minimise adverse effects on the coastal environment.

4.

Hard protection structures, where considered necessary to protect private assets, should not be located on public land if there is no significant public or environmental benefit in doing so.

The NZCPS provides a strong direction on managing the coastal edge in a way that recognises the potential effects of climate change and the need for communities to adapt over time to ensure that public values such as natural character, access, amenity and significant landforms such as dunes are not lost for future generations. There is a clear directive to manage “inappropriate” development and in the context of coastal hazards this includes controlling development and encouraging managed retreat in certain areas. There is also a strong directive about hard protection works. While the Operative District Plan has been prepared in a manner that gives effect to the NZCPS, the District Plan Review project represents the first opportunity to incorporate the relevant considerations of the three National Policy Statements (and the overlapping components of the NZCPS) in a comprehensive manner. Provision has now been made within the revised set of objectives, policies and methods associated with natural hazards to enable the Plan to give effect to the NZCPS. The NZCPS policies have been comprehensively addressed in the Coastal Environment chapter. In addition the NZCPS natural hazards policies have been given effect to in the Natural Hazards chapter. The General policies, specifically proposed Policies 9.2-9.7 and methods in the Natural hazards subchapter relate to coastal hazards as well as the natural hazards listed in this sub chapter. The precautionary approach in NZCPS Policy 3 has been implemented by including a freeboard in flood modelling and taking a conservative approach to the assessment of coastal erosion hazards. This has been achieved by using a relatively high value (1m) for sea level rise in the 100 year assessments. Continuation of historic accretion was not assumed due to a lack of knowledge about the cause of the accretion and whether it will continue in light of climate change effects. NZCPS Policies 24-27 are primarily given effect to in the Coastal hazards section of the Coastal Environment Chapter and supported by proposed Policy 9.5. This proposed policy focuses on natural systems as a form of hazard protection to give s32 Report – Natural Hazards  

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effect to NZCPS Policy 26, and proposed Policy 9.3 which gives effect to NZCPS Policy 25. The other three NPS’s are not relevant to natural hazards.  

3.3

Wellington Regional Policy Statement

As at the date of notification of the District Plan Review documentation, the Proposed Wellington Regional Policy Statement, 2009 (the “PRPS”) is still the subject of appeals to the Environment Court. Accordingly, the provisions of the Operative Regional Policy Statement, 1999 (the “RPS”) must be given effect to by the proposed provisions of the Kāpiti District Plan, and regard must be had to the provisions of the PRPS. Key relevant objectives and policies of the Operative Wellington RPS are as follows: Natural Hazards Objective 1: Any adverse effects of natural hazards on the environment of the Wellington Region are reduced to an acceptable level. Policy 1: To ensure that there is sufficient information available on natural hazards to guide decision making. Policy 2: To consider all of the following matters when planning for, and making decisions on, new subdivision, use, and development in areas which are known to be susceptible to natural hazards: (1) The probability of occurrence and magnitude of the natural hazards, and the location of the effects, including any possible changes which might arise from climate change; (2) The potential consequences of a natural hazard event occurring, both on-site and off-site. Potential loss of life, injury, social and economic disruption, civil defence implications, costs to the community, and any other adverse effects on the environment should be considered; (3) The measures proposed to mitigate the effects of natural hazard events, the degree of mitigation they will provide, and any effects on the environment from adopting such measures; (4) Alternative measures that might be incorporated into the subdivision, use and development to mitigate the effects of natural hazard events, the degree of mitigation they will provide, and any effects on the environment from adopting such measures. Both structural and non-structural measures should be considered; (5) The benefits and costs of alternative mitigation measures; (6) The availability of alternative sites for the activity or use; and (7) Any statutory obligations to protect people and communities from natural hazards. Policy 3: To recognise the risks to existing development from natural hazards and promote risk reduction measures to reduce this risk to an acceptable level, consistent with Part II of the Act. Policy 4: To ensure that human activities which modify the environment only change the probability and magnitude of natural hazard events where these changes have been explicitly recognised and accepted. s32 Report – Natural Hazards  

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Policy 5: To encourage people and communities to prepare for the occurrence of natural hazard events by providing them with relevant information and advice. Policy 8: To manage soils in such a way that the risks of flooding, erosion, land movement and subsidence are reduced to a level which is acceptable to the affected community. Soils and Minerals Objective 3: Land uses within river catchments are consistent with downstream river management and water use requirements, and do not undermine catchment resilience to storm damage and other natural calamities. Coastal Environment Objective 1: The natural character of the coastal environment is preserved through: (2) The protection of the integrity, functioning and resilience of physical and ecological processes in the coastal environment; Policy 2: To consider, where relevant and to the appropriate extent, the following matters when planning for and making decisions about subdivision, use or development in the coastal environment: (4) The potential impact of projected sea level rise; Policy 6: To adopt a precautionary approach to the evaluation of risk in making decisions that affect the coastal environment, recognising that there will be situations where there is a low probability of an event occurring, but that such an event has the potential to create major adverse effects. Such events include: (1) Earthquakes and tsunami; (2) Maritime shipping disasters; and (3) Accidents involving release of contaminants into the coastal marine area. The Natural Hazards subchapter has given effect to natural hazard Policy 2 and soil and minerals Policy 6 by taking a risk based approach of considering both the probability of an event and its consequences when considering the appropriate planning controls to apply to development in hazard prone areas. This includes linking development controls to building types and requiring hazard free building sites as part of subdivision. Alternative sites have been considered with a clear difference in activity status between locating building in areas prone to hazards and locating out of hazard prone areas on the same site. Natural hazard Policy 3 has been given effect to by methods which restrict development in hazard prone areas with stronger restriction for development could result in significantly greater consequences, due to it being 

critical infrastructure;

likely to have hazardous materials or;

likely to have large numbers of people.

Natural hazard Policy 4 has been given effect to by specifying in the policies or explanation to them the modelling assumptions made for the hazard assessment. In addition, residual risk areas have been identified for flooding and buffer areas and

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are provided within the fault voidance zones and coastal erosion management areas mapped in the Natural Hazard Maps. Natural hazard Policy 5 and soil and minerals Policy 6 have been given effect to by proposed Policies 9.7 and 9.17 which are implemented by non regulatory methods undertaken by the regional emergency management team. Soil and minerals policy 8 has been given effect to by proposed Policies 9.18 and 9.19 which minimise development on erosion prone land and further policies in the natural environment chapter relating to vegetation removal and the rural environment chapter relating to forestry harvesting. Soil and minerals policy 2 is primarily given effect to in the Coastal Environment chapter but is also given effect to by flood policies and methods in this chapter as climate change effects have been included in the flood modelling used to generate flood maps and categories for this plan. Key relevant objectives and policies of the PRPS include: Objective 18: The risks and consequences to people, communities, their businesses, property and infrastructure from natural hazards and climate change effects are reduced. Objective 19: Hazard mitigation measures, structural works and other activities do not increase the risk and consequences of natural hazard events. Objective 20: Communities are more resilient to natural hazards, including the impacts of climate change, and people are better prepared for the consequences of natural hazards events. Policy 28: Avoiding subdivision and inappropriate development in areas at high risk from natural hazards Regional and District plans shall: (a) identify areas at high risk from natural hazards; and (b) include policies and rules to avoid subdivision; and (c) include polices and rules to avoid inappropriate development in those areas. Policy 50: Minimising the risks and consequences of natural hazards When considering an application for a resource consent, notice of requirement, or a change, variation or replacement review to a district or regional plan, the risk and consequences of natural hazards on people, communities, their property and infrastructure shall be minimised, and/or in determining whether an activity is inappropriate having particular regard shall be given to: (a) the frequency and magnitude of the range of natural hazards that may adversely affect the proposal or development, including residual risk; (b) the potential for climate change and sea level rise to increase the frequency or magnitude of a hazard event; (c) whether the location of the development will foreseeably require hazard mitigation works in the future; (d) the potential for injury or loss of life, social disruption and emergency management and civil defence implications - such as access routes to and from the site; (e) any risks and consequences beyond the development site; (f) the impact of the proposed development on any natural features that act as a buffer, and where development should not interfere with their ability to reduce the risks of natural hazards;

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(g) (h) (i)

Natural Hazards

avoiding inappropriate development in areas at high risk from natural hazards; the potential need for hazard adaptation and mitigation measures in moderate risk areas; and the need to locate habitable floor areas and access routes above the 1:100 year flood level, in identified flood hazard areas.

Policy 51: Minimising adverse effects of hazard mitigation measures When considering an application for a resource consent, notice of requirement, or a change, variation or replacement review of to a district or regional plan, for hazard mitigation measures, particular regard shall be given to: (a) the need for structural protection works or hard engineering methods; (b) whether non-structural or soft engineering methods are a more appropriate option; (c) avoiding structural protection works or hard engineering methods unless it is necessary to protect existing development or property from unacceptable risk and the works form part of a long-term hazard management strategy that represents the best practicable option for the future; (d) the cumulative effects of isolated structural protection works; and (e) residual risk remaining after mitigation works are in place, so that they reduce and do not increase the risks of natural hazards. These objectives and policies build on the RMA and the NZCPS and place emphasis on assessing risks and managing them in a way that reduces the risks. In assessing risk there is a need to address the potential impacts of climate change, along with aiming to build communities that are more resilient to the potential impacts of natural hazards and recognising that climate change will exacerbate these hazards. Policy 28 requires District Plans to identify high risk areas and to avoid subdivision and inappropriate development in these areas. Policy 50 focuses on minimising the risk and consequences on people, communities, property and infrastructure. Policies 50 and 51 outline a range of matters that must be considered when assessing if activities are “appropriate”.  These objectives and policies have been given effect to in the Natural Hazards subchapter in conjunction with provisions in the coastal environment chapter. This is achieved by assessing climate related hazards, including flood and coastal erosion hazards, (potentially affected by climate change effects) using a 100 year assessment and incorporating consideration of likely climate change effects and consequently restricting new development in hazard prone areas. The assessment criteria in Policy 50 have been incorporated into policies and matters of control or discretion for resource consents in the Natural Hazards chapter and the Coastal Environment chapter.

3.4

Wellington Regional Plans

The Wellington Regional Council administers 5 Regional Plans, being:     

Regional Air Quality Management Plan; Regional Coastal Plan; Regional Freshwater Plan; Regional Soil Plan; and Regional Plan for discharges to land

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Section 75(4)(b) of the RMA states that any District Plan must “not be inconsistent with” a regional plan for any matter stated in s30(1) (functions of regional councils, including the avoidance or mitigation of natural hazards). Regional Coastal Plan General Objectives 4.1.11 Any adverse effects from natural hazards are reduced to an acceptable level. 4.1.12 That the location of structures and/or activities in the coastal marine area does not increase the risk from natural hazards beyond an acceptable level. General Policy 4.2.21 Use and development of the coastal marine area must take appropriate account of natural hazards… Objectives for structures includes: 6.1.1 Appropriate structures which enable people and communities to provide for their economic and social well-being are allowed. 6.1.2 There is no inappropriate use or development of structures in the coastal marine area. Policy for Structures: 6.2.2 To not allow the use or development of structures in the coastal marine area where there will be: …significant adverse effects on: • the risk from natural hazards; 6.2.3 To discourage the development of ad hoc shore protection structures; and to not allow the development of seawalls, groynes, or other "hard" shore protection structures unless all feasible alternatives have been evaluated and found to be impracticable or to have greater adverse effects on the environment. 6.2.5 To ensure that adequate allowance is made for the following factors when designing any structure: • rising sea levels as a result of climate change, using the best current estimate scenario of the International Panel on Climate Change (IPCC); • waves and currents; • storm surge; and • major earthquake events. Objectives for deposition 8.1.2 Beach nourishment is used as a means of mitigating the adverse effects of coastal erosion. Policy for Deposition: 8.2.1 To allow the deposition of sand, shingle, shell or other natural material on areas of foreshore or seabed if the purpose of that deposition is to combat beach or shoreline erosion, or to improve the amenity value of the foreshore, provided that all of the following criteria can be met: • the composition of the material is suitable for the site, will remain on the foreshore or seabed for a reasonable period of time, and will not result in increased water turbidity or wind borne sediment transport; • the deposition will not adversely affect the amenity value of the foreshore or seabed through significant changes in beach slope or texture; and • the deposition will not cause any significant adverse effects on marine fauna or flora, or human values or uses of the area. The RCP, while managing the area from MHWS seawards, addresses natural hazard risks. The Plan recognises that some structures may be located in the coastal marine area, for the management of hazard risk, but that in utilising structures they s32 Report – Natural Hazards  

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must be “appropriate” and other feasible alternatives must have been considered. Beach nourishment is supported as a method for managing the effects of hazards. It is noted that there is a range of other policies (in addition to the above) that also impact on the management of natural hazard effects. These include for example, natural character, amenity, landscape, public access. These are matters that are also addressed in the operative District Plan for the landward side of MHWS. The regional coastal plan is most relevant to the Coastal Environment chapter, however the provisions proposed in the Natural Hazards chapter are not inconsistent with the relevant provisions of the regional coastal plan relating to natural hazard management.

3.5

Iwi Management Plans

  Section 74(2A) of the RMA states that the territorial authority must “take into account” any planning document recognised by an iwi authority. Proposed Ngāti Raukawa Ōtaki River and Catchment Iwi Management Plan 2000 The plan provides a vision for Ngāti Raukawa and policy to guide the fulfilment of that vision. The Vision: 2.1.1 The mauri of the Ōtaki River and its people restored and revitalised. 2.1.1.1 To seek the protection and ongoing enhancement of the mauri of the Ōtaki River and Catchment, the fulfilment of Ngāti Raukawa kaitiakitanga responsibilities and the transferral of those responsibilities to future generations empowered and prepared to accept them. Secondary Vision Statement The mauri of the Ōtaki River and Catchment is protected, sustained, nurtured and enhanced so that Ngāti Raukawa in turn may be protected, sustained, nurtured and enhanced by it. Policy directions set out in section 4.1 include: 

Management guided by environmental principles (as at 2000 “to be prepared”); having a common base-line of protection and enhancement of mauri;

Pending the preparation of those principles, a precautionary approach is to be taken.

Ecological Restoration: Objective: To ensure that all future management decisions lead cumulatively to the enhancement of the mauri of the Ōtaki River and Catchment. Policy: that all policy established by agencies must seek ultimately to restore the natural processes necessary for a healthy functioning ecosystem.

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Environmental Monitoring Objective: To ensure effective and accurate monitoring of the health of the Ōtaki River environment. Policy: Ngā Hapū o Ōtaki will consider five primary indicators when monitoring the health of the environment of the Ōtaki River: … (iii) the abundance and spread of toheroa(coastal) (iv) the abundance and spread of tamure (marine)… This proposed Iwi Management Plan was produced in 2000. While the focus is strongly on the management of the Ōtaki River and catchment, there is also a strong reminder that this area is linked to the coastal areas and what happens upstream impacts on the coast. There is emphasis placed on integrated management that will restore the mauri and the quality of the environment. Kakapanui: Te Rūnanga o Āti Awa ki Whakarongotai Inc: Ngā Kōrero mo Te Taio: Policy Statements Manual The intent of this Iwi Management Plan is to develop community based solutions for environmental awareness, protection and management through a Treaty partnership process, and to protect the interests of future generations. Key principles that have been presented through other modules include: 

Adopting a precautionary approach

Ensuring that environmental health is maintained

Progressively improving and restoring the natural and healthy state of waterways and land (including sea, estuary, coastline)

Acknowledging the value of the natural resources including coastlines

Restoring natural environments and ecosystems.

Of particular note are the following policies on stormwater: Policy 1: To oppose any level of untreated stormwater discharge to areas required for food. Policy 4: To progressively remove untreated discharges from all waterways and commence with a process of remedial action to heal these places. Policy 5: To maintain that rahui until monitoring shows an improvement in water quality that meets shellfish taking and tikanga safety standards. Policy 13: To promote a community “ethic of care” based on good stewardship as part of our responsibilities to future generations. The iwi management plans and policy statements have been taken into account when developing natural hazard provisions. The additional focus on erosion control, in conjunction with provisions in the rural environment, infrastructure and natural environment chapters are intended to minimise effects of sediment entering waterways as a result of earthworks and/or development.

3.6

Operative District Plan Provisions

The District Plan 1999 contains the following key provisions:

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A7 Vision: a district with communities informed of the risk of natural hazards and the response necessary to minimise risks. C1.1.Policy 1 highlights the importance of amenity values, including reference to the natural environment, natural processes and access. This is supported by Policy 2 which also addresses the natural environment. C.15 Natural Hazards This chapter of the District Plan includes earthquake and geological hazards, coastal hazards and flood hazards. Present Coastal Hazards are identified as including: long-term erosion of the shoreline, short term fluctuations in the shore line, erosion from river mouth migration and wind erosion of dunes. Objective 1.0 To manage activities and development within natural hazard prone areas so as to avoid or mitigate the adverse effects of natural hazards. Policy 1 Permit subdivision and development where the effects of natural hazards can be avoided, remedied or mitigated. Policy 2 Ensure services are designed to resist natural hazard events. Policy 3 Ensure appropriate uses, zones and performance standards are developed for areas known to be liable to flooding and erosion, coastal erosion and ground rupture from faults. Policy 4 Ensure there are flood and erosion free building sites within newly created allotments. Policy 5 Promote awareness of natural hazards encouraging the community to mitigate and avoid the adverse effects of hazards ~ through emergency management programmes and procedures and voluntary actions. Policy 6 Promote a viable alternative access to the north of the district in the event of an earthquake. Policy 7 Avoid and/or mitigate the potential adverse effects of flooding and erosion from major rivers and the sea on:  human life, health and safety,  private or community property,  flood mitigation works, and  other natural and physical resources when planning for and making decisions on new subdivision, use and development within river corridors and adjacent to the sea.

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Policy 8 Recognise the ability of natural features (such as sand dunes and river berms) to buffer development from natural hazards through performance standards including minimum setbacks for new and relocatable buildings. Policy 9 When assessing discretionary activities within a river corridor, ponding area, overflow path, flood erosion area or flood storage area consider the following:  The effects of the development on existing flood mitigation structures.  The effects of the development on the flood hazard - in particular flood levels and flow.  Whether the development redirects floodwater onto adjoining sites or other parts of the floodplain.  Whether the development reduces storage capacity and causes adverse effects on adjoining sites or other parts of the floodplain.  Whether access to the site/development will adversely effect the flood hazard. Policy 10 Apply a higher level of control to subdivision and development in direct risk flooding areas, with a generally lesser level of restriction in residual overflow risk areas and no controls within residual ponding risk areas Policy 11 To adopt a risk based approach to subdivision and development within Fault Avoidance Zones. A risk-based approach shall take into account Recurrence Interval Classes (RIC), Building Importance Categories and Fault Complexity Zones (i.e. how defined the fault trace is - Well-Defined, Well-Defined Extension, Distributed, Uncertain-Constrained or Uncertain-Poorly Constrained). A risk based approach assesses the risk posed by the fault hazard in conjunction with the type of development being sought to determine whether the risk is to be avoided or mitigated. The likelihood of the hazard occurring is higher in the Class II faults and progressively lessens through Class III and Class IV faults. Policy 12 When assessing subdivisions and developments which are located within a Fault Avoidance Zone, a risk management approach shall be adopted and Council will consider range of matters that seek to reduce the risk to building failure and loss of life from a fault rupture hazard, including:  Geotechnical information provided by a suitably qualified person demonstrating that any building is not located on a fault trace or fault trace deformation and maintains a reasonable set back distance in accordance with any geotechnical recommendations; and  The intensity of the subdivision and nature of future development of the site, including building design and construction techniques, and the likelihood of building failure and/or loss of life if the fault ruptured in a person’s lifetime; and  With the exception of Type 2c, 3 and 4 buildings, it is not necessary to avoid or mitigate potential effects along the Southeast Reikorangi Fault; and excluding the Well-Defined and Well-Defined Extensions zones, along the Gibbs and Ōtaki Forks faults.

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Proposed Kāpiti Coast District Plan

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Policy 13 Avoid higher density and higher risk uses such as commercial and industrial activities within the Fault Avoidance Zones where they are identified in the Risk Management Approach Model.

3.7

Other Plans & Strategies

Another matter to which Council must have particular regard are other management plans and strategies prepared under other Acts. Those which are relevant to the Kāpiti Districts natural hazards are discussed below. Section 74(2) of the RMA states that a territorial authority “shall have regard to” any management plans and strategies prepared under other Acts. This section of the report discusses other documents considered in the development of this report. The following key documents have informed the preparation of this report and should also be considered as a part of the overall RMA section 32 process. Kāpiti Coast District Plan Review: Discussion Document Natural Hazards and Managed Retreat, 2010 This discussion paper was one of a set of papers which formed the basis for discussing issues of importance to the District Plan Review. It provides a comprehensive overview of natural hazards and the challenges being faced. It also outlines the legislative background to managing hazards. Managed retreat is discussed as a key method for risk reduction, along with recognition that a multi-year community discussion is required. The document identifies (p8) that there is a need to address natural hazard risks in a way that:  Provides for certainty  Plans for continuous change  Plans for an uncertain threat  Works with communities to find sustainable, long-term solutions. The document also recognises that the District Plan is only one mechanism (albeit a key one), for managing natural hazards and the associated risks to people and property. The development of this report has drawn strongly on this Discussion Document. Choosing Futures: Coastal Strategy, 2006 This KCDC Strategy builds on the Kāpiti Coast: Choosing Futures: Community Outcomes and Community Plan. It was developed to guide management of the coastal environment over the next 20 years and to implement the community vision of “restore and enhance the wild natural feel of the coast”. The community also wanted to see a comprehensive and integrated approach to coastal management (not just protection) which treats the coast as an ecosystem to be managed as a whole”(p16). The District Plan is one of the regulatory tools for implementing this strategy. In relation to coastal hazards the following were particularly noted:

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Overarching Objective: That environmental and lifestyle values that have always attracted people to the area are retained and enhanced and the historical, geological and cultural values are maintained”. District-wide coastal outcomes: 

Public dune margins are no longer gardened with exotic species by adjacent owners.

Restoration planting has been a priority on the foredune and has formed a natural erosion buffer.

All access to the beach across the foredune is via a public accessway as these are suitable for all users and protect the environment.

Any structures within the coastal reserve (protection and access structure) are part of the built character and must be well designed and multipurpose where possible.

Improved understanding that the Coast is a single, contiguous natural resource, and that the coastal margins in front of public and private assets should be managed in a holistic way.

Management Principles: 

Long-term solutions which protect coastal processes and systems are sought for the benefit of current and future generations.

Unique areas and interest along the coast are recognised and solutions are sought which protect character and the environment. This means management practices reflect that different parts of the coast have different needs.

Private and public access is balanced within the constraints of coastal systems.

Emergency management strategies and related processes are planned in advance of possible events.

The coastal reserve and dune margins are treated and understood as an integrated natural system and managed as a community asset.

Erosion and other coastal hazards along with the built character of coastal development were identified as two of the seven main challenges for coastal management (p24). The strategy (p51–59) provides an overview of coastal hazards along with outlining the erosion/accretion and hazards trends experienced along the Kāpiti Coast. It notes in particular the range of engineered structures that have been put in over time to address erosion effects. It identifies that a revised assessment of coastal hazard risk was undertaken and that a review of the building setback lines would also be undertaken. It states: The overall strategic response for hazards is to continue to protect existing structures on the coast while maintaining the dune areas, making them as natural as possible with native plantings and to consider soft engineering as an initial response to problems. (p55). A range of responses (many of which fall outside the scope of the District Plan) are identified to meet this challenge. In particular it is noted that Council’s intention is to continue to protect only public assets. s32 Report – Natural Hazards  

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The strategy (pp 60–62) also reflects on the built environment. It states: The overall strategic response is to protect character areas in the District Plan, ensure any building setbacks from the coast include consideration of amenity and ensure protection works are as minimal as possible and do not change the character of settlements. A range of responses are identified to meet this challenge, including in particular ensuring new buildings are set back from the coast (for visual and amenity purposes) but also recognising the hazard role of setbacks. The Council stated it intended to retain the 70 m (Peka Peka) and 100 m (rural) setbacks. The Strategy has been had regard to in the following key areas:      

Sustainable management of the environment and restoration of environmental health. Addressing the effects of climate change and sea level rise on the coastal edge. Controlling the subdivision and use of land to avoid increasing hazard risk. Avoiding “inappropriate” subdivision, use or development. Taking precautionary and long-term strategic approaches. Discouraging shoreline structures but recognise they may be required in some areas.

The coastal strategy was developed to provide a holistic vision and management approach to coastal issues. Several key elements of the strategy are implemented through provisions in the Natural Hazards chapter and the Coastal Environment chapter. These relate primarily to retaining natural buffers and working with natural systems to mitigate hazards.

3.6

Trade Competition

Section 74(3) of the RMA requires that, in preparing or changing the District Plan, the Council must not have regard to trade competition or the effects of trade competition. In regard to the proposed natural hazards provisions, the Objective, Policies and other Methods are trade competition neutral.  

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4 EVALUATION OF PROPOSED OBJECTIVE 4.1

Proposed Objective

The District Plan’s objectives are the primary means to achieve the sustainable management purpose set out in Section 5 of the RMA. For the purposes of this analysis, the appropriateness of the proposed objective is considered, and additional options are assessed as alternative means of achieving the sustainable management purpose in section 5. The proposed objective for managing the District’s natural hazards is as follows: There are a number of objectives which are applicable to natural hazards such as 2.3 Development Management and 2.4 Coastal Environment however the two objectives listed below directly refer to natural hazards. While the other objectives will be assessed in their relevant Section 32 reports, it is considered that Objectives 2.3 and 2.5 are the most applicable to natural hazards areas and are assessed below. Although Objective 2.4 Coastal Environment is relevant to natural hazards, it is more appropriately assessed in the coastal environment section 32.

Objective 2.3 Development management To maintain a consolidated urban form within Existing Urban Areas and a limited number of Identified Growth Areas which can be efficiently serviced and integrated with existing townships, delivering: c) resilient communities where development does not result in an increase in risk to life or severity of damage to property from natural hazard events; Objective 2.5 Natural hazards To ensure the safety and resilience of people and communities by avoiding exposure to increased levels of risk from natural hazards, while recognising the importance of natural processes and systems.

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4.2

Natural Hazards

Does the Objective Achieve the Act’s Purpose?

The following table summarises the extent to which the proposed objective achieves the purpose of the RMA. Purpose of RMA

Achievement

Sustain the potential of natural and physical resources to meet needs of future generations (s5(2)(a))

Objective 2.3(c) seeks to deliver resilient communities where development does not result in an increase in risk to life or severity to property from natural hazards. By maintaining the safety and integrity of the built environment from natural hazards, Objective 2.3(c) is sustaining the physical resources of the community. The Objective takes the approach of allowing development in low risk areas and thus sustains the built physical resource for future generations. This proposed objective recognises that managing what is essentially a natural process through managing the built environment will enable future generations to experience a reduced level of risk from such events. In this regard, Objective 2.5 achieves this part of Section 5 of the Act. Objective 2.5 seeks to ensure the safety and resilience of people and communities by avoiding exposure to natural hazards. Natural hazards have the potential to not only threaten the safety of the community but also integral structural components that are needed for a community to function such as roading, electricity, telecommunications etc.

Safeguard the life-supporting capacity of air, water, soil and ecosystems (s5(2)(b))

Inappropriate development, such as building in flood prone areas, or behaviour or lack of awareness of natural hazards can increase the exposure of people and communities to risks from natural hazards. A key issue for the District is avoiding areas at risk of natural hazards, or where development exists already adopting mitigation measures to lessen the impacts of natural hazards. This part of Section 5 is not applicable to Objective 2.3(c) but is addressed by other objectives. Objective 2.5 recognises the importance of natural processes and systems. It is important that the natural processes can continue with minimal interference (i.e. without being constrained by development or other physical structures). Although the Objective does not specifically safeguard the life-supporting capacity

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Proposed Kāpiti Coast District Plan

Purpose of RMA

Avoid, remedy or mitigate adverse effects of activities on the environment (s5(2)(c))

Natural Hazards

Achievement of air, water, soil and ecosystems, natural processes and intrinsically linked to these natural assets. By recognising the importance of natural processes and systems, the life-supporting capacity will also be safeguarded. The definition of “environment” as contained in the RMA includes ecosystems and their constituent parts, including people and communities. As Objective 2.3(c) seeks to reduce the risk to life from natural hazard events, it is considered to achieve this part of Section 5 of the Act. The definition of “environment” as contained in the RMA includes ecosystems and their constituent parts, including people and communities. As Objective 2.5 seeks to ensure the safety and resilience of people and communities by avoiding increased levels of risk from natural hazards, it is considered to achieve this part of Section 5 of the Act. It also ensures that activities are managed in a way that reduces the potential impacts of natural hazard events on property and life while preserving the natural environment.

Enable people and communities to provide for their social, economic and cultural well-being (s5(2))

Objective 2.3(c) seeks to limit the risk or severity to property from natural hazard events. Objective 2.5 seeks to ensure that communities are located and designed in a way to reduce the potential impacts on them from hazard events. There are potentially high economic and social costs associated with natural hazards in the District with significant consequences for public health and safety, agriculture, housing and infrastructure. Natural hazard events not only disrupt the social fabric of the community but can have devastating effects on assets such as structures and infrastructure. Both proposed objectives seek to reduce the social and economic costs by avoiding exposure to increased levels of risk. Both Objectives 2.3(c) and 2.5 will enable people and communities to provide for their social, economic and cultural well-being by reducing the risk from natural hazards.

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Purpose of RMA

Achievement

Enable people and communities to provide for their health and safety (s5(2))

Objective 2.3(c) directly recognises that natural hazard events have the potential to risk life. This objective will achieve this part of Section 5 of the Act by providing for the health and safety of communities through not increasing the risk to life from natural hazard events By seeking to avoid exposure to risk from hazard events, Objective 2.5 contributes to the health and safety of individuals and communities.  Inappropriate development, such as building in flood prone areas, or lack of awareness of natural hazards can increase the exposure of people and communities to risks from natural hazards. Avoiding exposure to increased level of risk from natural hazards will provide for the health and safety of the community in accordance with this part of Section 5 of the Act. Objective 2.5 seeks recognises the importance of natural processes and systems. Although this wording does not match that in Section 6, preserving natural processes and systems will ensure the preservation of the natural character of the coastal environment and the protection of areas of significant indigenous vegetation and significant habitats of indigenous fauna. Of most relevance are the following parts of Section 7:

Matters of National Importance (s6)

Other Matters (s7)

(f) maintenance and enhancement of the quality of the environment: (i) the effects of climate change: The definition of “environment” as contained in the RMA includes ecosystems and their constituent parts, including people and communities. As Objectives 2.3(c) and 2.5 seek to ensure the safety and resilience of people and communities by avoiding increased levels of risk from natural hazards, it is considered to achieve Section 7(f). The effects of climate change must be considered in tandem with natural hazards. The Council recognises that climate change has the potential to increase both the frequency and magnitude of natural hazard events. Long-term planning needs to take account of expected long-term shifts and changes in climate extremes and patterns to ensure future generations are adequately prepared for predicted climate conditions, and that a precautionary approach is taken to hazard s32 Report – Natural Hazards  

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Proposed Kāpiti Coast District Plan

Purpose of RMA

Natural Hazards

Achievement mitigation and avoidance. Reducing the exposure of people and property to risk from natural hazard events and potential climate change impacts would not only result in less impact on people and communities but would also enable the natural environment to respond and adjust in a natural way. In this regard, both Objectives 2.3(c) and 2.5 are considered to give appropriate regard to the effects of climate change.

In summary, it is concluded that the proposed Objectives achieve the purpose of the Act and promotes the sustainable management of natural and physical resources in a way that people and communities can provide for their social, economic and cultural wellbeing, and for their health and safety, both now and in the future.

4.3

Is the proposed objective the most appropriate to achieve the Act’s purpose?

In determining the most appropriate objective to achieve the purpose of the Act, the test is the extent to which each objective is the most appropriate way to achieve the purpose of the Act. All of the proposed objectives under the District Plan Review have been written to interrelate and achieve an overlapping framework of sustainable resource management. In this context, the most appropriate objective does not necessarily equate to the superior objective – rather it is a matter of suitability, given the other objectives proposed. To this end, the District Plan Review project entails a reduction in the overall number of objectives from 43 (in the Operative Plan) to a new total of 20. As illustrated in section 4.2 of this report, the proposed natural hazards objectives achieve the purpose of the Act. Within the framework created by the 20 proposed objectives, it is also considered to be the most appropriate means of achieving the Act’s purpose with respect to natural hazard matters. There was one main objective regarding natural hazards in the Operative Kāpiti Coast District Plan, contained in Section C15 as follows: Objective 1.0 To manage activities and development within natural hazard prone areas so as to avoid or mitigate the adverse effects of natural hazards. The objective has two main parts to it:  

Manage activities and development within natural hazard prone areas And in doing so, avoid or mitigate the adverse effects of natural hazards

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The proposed objectives introduce quite a different approach to natural hazard management. There is a greater awareness of what the outcomes sought are e.g. no increase in risk to life or severity to property, and the safety and resilience of people and communities. Proposed Objective 2.3(c) acknowledges the need to manage development and the increased risk to life and property when development is inappropriately located. Proposed Objective 2.5 only seeks to avoid exposure to increased levels of risk from natural hazards. Proposed Objective 2.5 is referring to not only the built form but activities also. Proposed Objective 2.5 introduces a new recognition of the importance of natural processes and systems. Natural hazards are after all just natural processes and it is only where the human environment intersects that natural hazards create issues. The objective was amended to provide greater clarity about the outcome sought reduction in level of exposure of people to natural hazard risks not just damage to buildings and structures while protecting natural systems to recognise that natural systems are the most resilient defence to natural hazards. The increasing risks associated with climate change effects also require recognition of the dynamic nature of many natural hazards and the need to address residual risks where structures currently protect people. On the basis of the above analysis, it is considered that the proposed objectives are the most appropriate for achieving the purpose of the RMA. The proposed objectives are deemed to be more appropriate for achieving the purpose of the Act than the status quo.

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5 EVALUATION OF PROPOSED POLICIES Essential to the potential future achievement of the proposed natural hazard objectives, the report now considers the matter of implementation. This is achieved firstly through evaluation of proposed policies, which are in turn implemented through the rules and other methods. This implementation evaluation must also consider the appropriateness of the policies and rules, including an assessment of their costs and benefits. The final implementation consideration is the extent to which any risk may be present in proceeding with the proposed policies and rules and other methods if there are any identified information gaps.

5.1

Do the proposed policies achieve the objective?

The following provides evaluations of whether the policies that apply to the objectives are the most appropriate for achieving the objectives, having regard to efficiency and effectiveness and taking into account the benefits and the costs of the policies. Because two objectives apply to natural hazards, policies will be assessed against the most relevant objective(s). The following policies are proposed to implement the objective: Policy 9.1 – Identify Hazards The extent of flooding, seismic, slope instability and erosion hazards in the District will be identified on the District Plan maps. Explanation: The extent of flood, earthquake fault rupture, coastal erosion, river erosion and slope instability hazard areas has been modelled to identify development control areas, which are identified on the district planning maps to provide certainty to property owners. The identification of natural hazards is an ongoing activity carried out by District and Regional Councils as part of the monitoring of the environment. Policy 9.1

Benefits  Ensures hazards are identified  Provides clarity and certainty to the community through identifying hazards on the District Plan maps  Enables activities, development and subdivision to be controlled in areas subject to hazards to lessen the risk to people and the community.  Enables efficient forward planning for these areas to ensure additional assets and people are not put at risk

Costs  Restricts development in these areas  May reduce the economic value of sites in these overlays  There will be inherent inaccuracies – some properties will be incorrectly identified whilst others may be left out  Does not quantify the risk e.g. the frequency, magnitude or duration of risk  Based on theoretical models which may not accurately forecast the future

Policy 9.2 Risk based approach: A risk based, all hazards approach will be taken to subdivision, land use, and development within areas subject to the following natural hazards: s32 Report – Natural Hazards  

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a) flood hazards; b) earthquake hazards; c) fire hazards; d) slope instability and erosion; and e) coastal erosion hazards Hazard risk categories will be developed for flood, earthquake and erosion hazards to guide minimising the risk of loss of life and damage to property due to these hazards, while allowing appropriate use in lower risk areas. Explanation: The District Plan manages risk through risk categories. These categories take into account the probability of the hazard and risk of loss of life or property as a consequence of allowing development in areas prone to hazard risk. Policy 9.2

Benefits  Ensures hazards are identified  Enables activities, development and subdivision to be controlled in areas subject to hazards to lessen the risk to people and the community.  Enables efficient forward planning for these areas to ensure additional assets and people are not put at risk.  Quantifies the risk rather than a blanket approach  Minimises the loss of life and damage to property in high risk areas  Allows appropriate uses in lower risk areas  Identifies where risks from natural hazards are most significant

Costs  Restricts development in these areas  May reduce the economic value of sites in these overlays  There will be inherent inaccuracies – some properties will be incorrectly identified whilst others may be left out  Does not quantify the risk e.g. the frequency, magnitude or duration of risk  Based on theoretical models which may not accurately forecast the future

Policy 9.3 Hazard prone areas New subdivision and land use and development activities will be located to avoid highly hazard prone areas, identified in the District Plan Maps. Where a modelled risk can be removed, through mitigation, to allow development on part of a site, any mitigation must demonstrate the activities and development do not exacerbate the adverse effects of natural hazards for other people and properties including residual risks. Explanation: The approach to minimising the adverse effects of natural hazards is to avoid subdivision and development in high risk hazard prone areas. Mitigation measures need to be employed to reduce risk from the hazard(s) provided the mitigation measures do not exacerbate the effects of natural hazard on other properties. The onus is on the applicant to ensure there will be no additional hazard risk on or off site as a result of any proposed activity or development. Policy

Benefits

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Proposed Kāpiti Coast District Plan

9.3

Natural Hazards

 Enables activities, development and subdivision to be controlled in areas subject to hazards to lessen the risk to people and the community.  Avoids subdivision and development in high risk areas  Minimises the loss of life and damage to property in high risk areas  Encourages subdivision, land use and development into lower risk areas  Identifies where risks from natural hazards are most significant  Enables mitigation measures to be considered  Ensures mitigation does not exacerbate the adverse effects of natural hazards for other people and property

 Restricts development in these areas  May reduce the economic value of sites in these overlays  There will be inherent inaccuracies – some properties will be incorrectly identified whilst others may be left out  Additional cost on the developer to mitigate a theoretical risk

Policy 9.4 Precautionary approach A precautionary approach will be taken to subdivision and development where there is uncertainty about the potential effects of a hazard until further detailed information on the extent and nature of the hazard becomes available. Explanation: A precautionary approach means that development will only be enable where further site specific investigations identify that the activity proposed is appropriate to the natural hazard risks on the site. This approach will be taken to natural hazards that are present in the district but are not mapped in the district plan maps as there is poor information about the scale and extent of the hazard risks for those hazards. This includes potential liquefaction risk, slope instability, climate based hazards (flooding and coastal erosion) and fire risk. Policy 9.4

Benefits  Ensures a precautionary approach where there is uncertainty about hazard risk levels  Minimises the loss of life and damage to property

Costs  Restricts development in these areas  May reduce the economic value of sites in these overlays  Additional cost on the developer to undertake further site specific investigations  These areas will not be mapped in the District Plan maps due to poor information about the scale and extent of the hazard risk.

Policy 9.5 Protect via natural buffers Natural features which have the effect of reducing hazard risk by buffering development from natural hazards will be protected through development controls,

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including minimum setbacks, from the coast, rivers and streams for new and relocated buildings and enabling restoration of natural systems. Explanation: Dune systems act as a buffer between the land and the sea and can absorb the impacts of erosion, thereby protecting areas further landward. Protection, including restoration, of natural features is vital for their effective functioning as a buffer against natural hazards. Past use and development in some areas has degraded the effective ‘buffering’ potential of natural features e.g. dunes and wetlands, by encroaching on them Policy 9.5

Benefits  Protects natural features with the potential to buffer development from natural hazards  Increased protection for life and property  Minimises the loss of life and damage to property  Enables restoration of natural systems  Encourages restoration of natural features  Prioritises natural buffers over hard engineering solutions

Costs  May restrict development in areas where there are natural features  Increases the cost of development with requirements for restoration

Policy 9.6 Public open space The potential to mitigate natural hazards and climate change impacts will be considered in relation to the provision, acquisition and development of new land for public open spaces and reserves. Explanation: Open Space areas can play a major role in the mitigation of the effects associated with natural hazards, for example as a buffer to the effects of coastal hazards for beach settlements, or for stormwater attenuation, detention and secondary flowpaths. Policy 9.6

Benefits  Protects public open space with the potential to buffer development from natural hazards  Increased protection for life and property  Minimises the loss of life and damage to property  Increased resilience to natural hazard events  Enables more extensive public open space networks  Encourages restoration of natural features  Prioritises natural buffers over hard engineering solutions

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Costs  May restrict development in areas where public open space is required  Increases the cost of development with requirements for acquisition or development of public open space


Proposed Kāpiti Coast District Plan

Natural Hazards

Policy 9.7 Emergency management Preparation for the effects of natural hazard events and avoidance or mitigation of hazards will be encouraged through emergency management programmes and procedures, and voluntary action. Explanation: Increasing awareness of natural hazards assists with community preparedness. The policy promotes emergency management programmes and procedures, and voluntary action in line with the Civil Defence Emergency Management Act 2002. Emergency management initiatives include a range of measures across the four R’s of risk reduction, readiness, response, and recovery. Policy 9.7

Benefits  Increased awareness of natural hazards  Minimises the loss of life and damage to property  Increased resilience to natural hazard events  Promotes emergency management programmes and procedures  Requires Council to take an active role in the provision of natural hazard information to the public e.g. flood hazards

Costs  Costs incurred in preparing emergency management programmes

Policy 9.8 Flood mapping The 1 in 100 year flood modelling scenario has been used to generate flood map extents. The extents and categories include consideration of projected climate change and precautionary freeboard to minimise risks. Residual risks will also be mapped where flood mitigation structures are present. Policy 9.8

Benefits  Ensures flood hazards are identified  Provides clarity and certainty to the community through identifying flood hazards on the District Plan maps  Enables activities, development and subdivision to be controlled in areas subject to flood hazards to lessen the risk to people and the community.  Enables efficient forward planning for these areas to ensure additional assets and people are not put at risk  Incorporates climate change

Costs  Restricts development in these areas  May reduce the economic value of sites in these overlays  There will be inherent inaccuracies – some properties will be incorrectly identified whilst others may be left out  The 1 in 100 year flood modeling may not be the most appropriate  Based on theoretical models which may not accurately forecast the future

Policy 9.9 Flood risk categories Flood risk categories have been developed using the following criteria: a) depth and speed of floodwaters; b) the threat to life; s32 Report – Natural Hazards  

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c) difficulty and danger of evacuating people; d) the potential damage to property; and e) the potential for social disruption. Policy 9.9

Benefits  Ensures flood hazards are identified  Enables activities, development and subdivision to be controlled in areas subject to flood hazards to lessen the risk to people and the community.  Enables efficient forward planning for these areas to ensure additional assets and people are not put at risk.  Quantifies the risk rather than a blanket approach  The categorisation recognises not just the flooding risk but other variables such as the difficulty in evacuating people, risk to property, social disruption etc  Minimises the loss of life and damage to property in high risk flooding areas  Allows appropriate uses in lower risk areas  Identifies where risks from flooding are most significant

Costs  Restricts development in these areas  May reduce the economic value of sites in these overlays  There will be inherent inaccuracies – some properties will be incorrectly identified whilst others may be left out  Based on theoretical models which may not accurately forecast the future

Policy 9.10 Flood and erosion free building sites All newly created lots must have flood and erosion-free building sites based on 1 in 100 year flood modelling. Policy 9.10

Benefits  Increased protection for life and property  Minimises the loss of life and damage to property  Increased resilience to flooding events

Costs  Increases cost to development  Not all sites may be vulnerable to the 1 in 100 year flood risk but all are required to accommodate such a flood event  The 1 in 100 year flood modeling may not be the most appropriate  Based on theoretical models which may not accurately forecast the future

Policy 9.11 Flood risk levels A higher level of control on subdivision and development will be applied in direct and residual high risk flooding areas. These are areas identified as the river and stream corridors, overflow paths, flood storage, fill control areas and flood erosion areas, and

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a generally lesser level of restriction in lower risk areas including ponding, and residual ponding. Policy 9.11

Benefits  Enables development and subdivision to be controlled in areas subject to flooding hazards to lessen the risk to people and the community.  Avoids subdivision and development in high risk flooding areas  Minimises the loss of life and damage to property in high risk flooding areas  Encourages subdivision, land use and development into lower risk flooding areas  Identifies where risks from flooding are most significant

Costs  Restricts development in high risk flooding areas  May reduce the economic value of sites in these overlays  There will be inherent inaccuracies – some properties will be incorrectly identified whilst others may be left out  Additional cost on the developer to mitigate a theoretical risk

Policy 9.12 High hazard flood areas Development in the river and stream corridor, overflow path, flood erosion and flood storage areas will be avoided unless the 1 in 100 year risk can be completely mitigated on site to avoid damage to property or harm to people, and the following criteria are met; a) no increase in flood flow or level on adjoining sites or other parts of the floodplain; b) no reduction in storage capacity on site; and c) all flow corridors or overflow paths are kept clear to allow flood waters to flow freely at all times. Policy 9.12

Benefits  Avoids development and subdivision in areas subject to high flooding hazards to lessen the risk to people and the community.  Minimises the loss of life and damage to property in high risk flooding areas  Encourages subdivision, land use and development into lower risk flooding areas  Identifies where risks from flooding are most significant  Enables mitigation measures to be considered  Manages the effects of any proposed mitigation measures  Ensures that mitigation does not exacerbate flooding effects on adjoining sites

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Costs  Restricts development in high risk flooding areas  May reduce the economic value of sites in these overlays  There will be inherent inaccuracies – some properties will be incorrectly identified whilst others may be left out  Additional cost on the developer to mitigate a theoretical risk


Proposed Kāpiti Coast District Plan

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 Ensures no reduction in storage capacity on site  Al flow corridors or overflow paths are kept clear to allow flood waters to flow freely

Policy 9.13 Ponding, residual ponding, and fill control areas When assessing application for subdivision or development within a ponding, residual ponding or fill control area consider the following: a) the effects of the development on existing flood mitigation structures; b) the effects of the development on the flood hazard – in particular flood levels and flow; c) whether the development redirects floodwater onto adjoining sites or other parts of the floodplain; d) whether access to the site/development will adversely affect the flood hazard. e) the extent to which buildings can be located on areas of the site not subject to flooding. f) whether any subdivision or development will or may result in damage to property or harm to people. Explanation: The policies promote a higher level of restriction in high risk flood areas including the river and stream corridor, overflow path (including residual overflow path), flood erosion and flood storage areas. The risks of flooding and erosion to the community are much greater in these high risk flood areas, therefore it is appropriate that district plan rules reflect a higher level of restriction than for lower risk areas. Policy 9.13

Benefits Costs  Increased cost to the developer to  Clearly sets out assessment address these criteria criteria for subdivision or development within ponding, residual ponding or fill control areas  Improved clarity as to what will be assessed  Enables the effects of the development to be considered in terms of the flood hazard  Ensures that mitigation does not exacerbate flooding effects on adjoining sites  Minimises the loss of life and damage to property in high risk flooding areas

Policy 9.14 Activities within a Fault Avoidance Area When assessing applications for subdivisions, land uses and developments which are located within a Fault Avoidance Area, a risk management approach has been adopted and Council will consider a range of matters that seek to reduce the risk to building failure and loss of life from a fault rupture hazard, including: a) Geotechnical information provided by a suitably qualified person demonstrating that any building is not located on a fault trace or fault trace s32 Report – Natural Hazards  

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deformation and maintains a reasonable setback distance in accordance with any geotechnical recommendations; and b) The intensity of the subdivision and nature of future development of the site, including building design and construction techniques, and the likelihood of building failure and/or loss of life if the fault ruptured in a within 50 years; and c) With the exception of BIC Type 2c, 3 and 4 buildings (see Table 9.2: Building Importance Category), it is not necessary to avoid or mitigate potential effects along the Southeast Reikorangi Fault; and excluding the Well-Defined and Well-Defined Extensions Areas, along the Gibbs and Ōtaki Forks faults. The risk management approach takes into account Recurrence Interval Classes (RIC), Building Importance Categories (BIC) and Fault Complexity. Policy 9.14

Benefits Costs  Increased cost to the developer to  Clearly sets out assessment address these criteria, including criteria for subdivision, land use the need for a geotechnical or development within a Fault assessment Avoidance Area  Improved clarity as to what will be assessed  Enables the effects of the development to be considered in terms of the fault hazard  Minimises the loss of life and damage to property  Reduces the risk of building failure  The risk management approach considers a number of variables including recurrence intervals, building importance and fault complexity.

Policy 9.15 Avoid high density and high risk uses in Fault Avoidance Areas Higher density and higher risk uses such as commercial and industrial activities, community buildings and multi-unit housing (BIC categories 3 and 4) will avoid locating within the Fault Avoidance Areas where they are identified in the Risk Management Approach. Explanation: Due to the potential for larger numbers of people to congregate or work in community facilities, multi-unit housing, commercial areas or similar uses, these types of facilities should not be located within the Fault Avoidance Areas. Industrial buildings and buildings used for the storage of hazardous substances entail unacceptable risks to people and to the environment if located on the fault trace. Policy 9.15

Benefits  Reduces the number of buildings and people in close proximity to faults  Minimises the loss of life and damage to property  Avoids damage to hazardous substance containers should an

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Costs  Restricts development in these areas


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event occur involving the fault line. This increases protection to the environment and community from hazardous substances Policy 9.16 Liquefaction prone land When assessing applications for subdivisions which are located on sandy, alluvial or peat soils, a risk management approach shall be adopted and Council will consider a range of matters that seek to reduce the risk to people and property, including: a) Geotechnical information provided by a suitably qualified person on liquefaction provided with any subdivision or development application; b) The intensity of the subdivision and nature of future development of the site, including building design and construction techniques; c) The risk to people and property posed by the liquefaction hazard and the extent to which the activity could increase the risk posed by the natural hazard. These investigations may result in identifying that some sites are not suitable for development and any such proposal would be declined. Explanation: The risk of liquefaction in the district is currently poorly understood. While a study is currently being undertaken of the risks, any subdivision which creates additional lots on land with sandy, alluvial or peat soils will need to undertake a site specific investigation to determine actual liquefaction susceptibility risks and provide that information as part of the subdivision consent application. Policy 9.16

Benefits Costs  Increased cost to the developer to  Clearly sets out assessment address these criteria, including criteria for subdivision, land use the need for a geotechnical or development within assessment liquefaction prone areas  Improved clarity as to what will be assessed  Enables the effects of the development to be considered in terms of potential liquefaction  Minimises the loss of life and damage to property  Reduces the risk of building failure

Policy 9.17 Tsunami Residents will be warned to evacuate high risk areas prior to an anticipated distant source Tsunami event and recommended to self evacuate in the event of a local earthquake. There will be no regulatory controls placed on development in high risk areas in this plan. Policy 9.17

Benefits  Minimises the loss of life and damage to property  Does not restrict development in desirable coastal locations

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Costs  May increase the risk to life and property by people living in close proximity to the coast


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Policy 9.18 Erosion Risk Assessment When assessing applications for subdivisions and developments which are located on land which has a moderate or high erosion risk, a risk management approach will be taken and Council will consider a range of matters that seek to reduce the risk to people and property, including: a) geotechnical information provided by a suitably qualified person on slope stability provided with any subdivision or development application; b) engineering information for mitigation or remediation works if practicable; c) the intensity of the subdivision and nature of future development of the site; d) any measures proposed to avoid or mitigate any potential effects on slope stability including the retirement and planting of steeper land. e) the extent to which any subdivision or building will, or may, result in damage to property or harm to people. f) the activity or any subsequent use of the land and the potential of those activities to increase erosion or instability or result in material damage to any structure or building on that land or any other land. Explanation: The areas of moderate or high erosion prone land are illustrated on the district planning maps. People wanting to undertake subdivision or development on land which has a moderate to high susceptibility to erosion will be required to provide a geotechnical assessment as part of their subdivision or land use consent application. Subdivision and development will not be undertaken on land where there is an erosion risk that cannot be remediated. Policy 9.18

Benefits Costs  Increased cost to the developer to  Clearly sets out assessment address these criteria, including criteria for subdivision, land use the need for a geotechnical or development within erosion assessment and engineering prone areas design  Improved clarity as to what will  May mean that some land can not be assessed be developed  Enables the effects of the development to be considered in terms of potential erosion  Minimises the loss of life and damage to property  Reduces the risk of building failure  Enables the risk to people and property to be assessed  Avoids subdivision and development on land where there is an erosion risk that can not be remediated.

Policy 9.19 Erosion Risk Avoidance Subdivision and development will avoid locating on land identified in the District Plan maps as having moderate or high erosion risk, unless a comprehensive engineering and geotechnical report demonstrates that the land is sufficiently stable for the subdivision or development activities proposed.

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Policy 9.19

Natural Hazards

Benefits  Minimises the loss of life and damage to property  Enables the risk to people and property to be assessed  Avoids subdivision and development in areas with moderate or high erosion risk  Ensures erosion risk hazard areas are identified  Provides clarity and certainty to the community through identifying hazards on the District Plan maps  Enables efficient forward planning for these areas to ensure additional assets and people are not put at risk

Costs  Increased cost to the developer to address these criteria, including the need for a geotechnical assessment and engineering design  May mean that some land can not be developed  May be inaccuracies in the modeling and not all land subject to a moderate or high erosion risk is identified

Policy 9.20 Fire hazards Risks to people and property from fire hazards will be required to be minimised by: a) Requiring plantation forestry and forestry harvesting activities in rural and open space zones to be designed to enable quick response to fire; and b) Requiring rural zones to provide water for firefighting; and c) Requiring access and adequate fire fighting water supplies to be provided for fire appliances in all zones. Policy 9.20

Benefits  Reduces the risk to people and property from fire hazards  Enables quick response to fire through design of plantation forestry and forestry harvesting  Ensures there is sufficient water for firefighting  Ensures sufficient water pressure and volume for firefighting

Costs  May require modification of design of plantation forestry and forestry harvesting

Efficiency These policies provide an efficient way to achieve Objective 2.3(c) and 2.5 as the benefits of managing the risk of natural hazards outweigh the costs. The primary benefits from the policies are the reduction in risk to life and property which will ultimately benefit the well-being of both current and future generations. The policies are efficient in that they provide mechanisms to achieve the objectives. For example the policies avoid subdivision, land use and development in high risk areas including erosion-prone land, fault avoidance areas and high risk flood areas. It is more efficient that development is avoided in areas with a high risk to natural hazards than to retrofit or mitigate damage at a later date. s32 Report – Natural Hazards  

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Effectiveness The proposed policies provide an effective framework to achieve Objectives 2.3(c) and 2.5 by providing mechanisms to minimise the risk of natural hazards to life and property. The policies address the gaps in the existing district plan by incorporating policies around land slippage and the risk of fire. They retain natural flood functioning and helps maintain productivity of other land in the catchment. The policies enhance the well-being of residents and landowners by protecting amenity values, environment, health and safety. They avoid on-going costs of recovery from floods, slips and other events. They support the protection of natural features, such as dunes and wetlands, as buffers, which in turn meet the values people appreciate about the natural environment. But overall the policies avoid exacerbating existing risk by requiring new buildings to be located away from areas at most risk, and preventing subdivision in hazard areas that could lead to expectations of future buildings. The policies are considered effective by ensuring that natural hazard risks are part of the planning for the future, and factored into development decisions.

5.2 What are the risks of acting or not acting if information gaps exist? The timing and severity of hazards events are often uncertain, however the effects of natural hazards are predictable using statistics. The extent of changes due to climate change has been researched extensively world-wide and there is general consensus on the findings. Nevertheless, forecasts retain some uncertainty. The risk of acting through the district plan is that land may be left undeveloped and not be used to its full potential during periods when no hazards occur. The risk of not acting through the District Plan is that development would occur in hazard prone areas and the next hazard event would have more serious impacts than if action is taken. These impacts could include more severe health and safety effects, damage to property, and increased disaster response and recovery costs. The development of policies was informed by a flood modelling report (SKM), a coastal hazard report (Coastal Systems) and an earthquake report (GNS).

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6 EVALUATION OF PROPOSED RULES AND OTHER METHODS 6.1

Do the proposed rules achieve the relevant objectives?

The following provides an evaluation of whether the methods/rules are the most appropriate for achieving the draft objectives, having regard to the efficiency and effectiveness of the methods/rules and taking into account their benefits and costs. Classification of activities Benefits            

  

Articulates a range of activities anticipated in a particular area Provides certainty to the community as to what activities / structures might establish. Encourages development that meets the standards (usually as a permitted or controlled activity) Discourages subdivision or development on land subject to two or more high risk hazard category. This lessens the risk to life and property. This effectively achieves Policy 9.3. The general approach of the classification of activities is to discourage development and subdivision in areas where there is high risk from natural hazard events. This is in accordance with Policy 9.2. Encourages development in residual ponding areas that meets the standards. This is in accordance with Policy 9.11. Avoids development and subdivision in overflow paths, residual overflow paths or flood erosion areas and implements Policy 9.12 Enables small structures in flood hazard areas Enables flood protection measures in appropriate locations Avoids damage or destruction of flood mitigation measures. This minimises the risk to the community from flood events. Discourages network utilities in an overflow or residual overflow path. This minimises the risk of damage to vital infrastructure as a result of flood hazards. Development in areas of earthquake hazards can occur, provided standards are complied with. The activity status in most cases enables the risk to be assessed and mitigated where appropriate. This effectively achieves Policy 9.14. Discourages network utilities in Fault Avoidance Areas. This minimises the risk of damage to vital infrastructure as a result of earthquakes. Subdivision and development in areas or erosion or slope instability require a resource consent which allows the effects and risk to be assessed. This is in accordance with Policy 9.18. Enables minor additions to existing habitable buildings as permitted activities as they are unlikely to significantly increase the risk to life or property. This is in accordance with Policy 9.18.

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Costs    

Administrative costs for Council associated with processing applications and assessing compliance. Potential additional regulatory costs to land owners and developers through a structured method of managing the District’s rural resource Additional time required to obtain a consent Additional cost in obtaining the necessary assessments to support a resource consent application

These rules (classification of activities) will be efficient to achieve Objective 2.3(c) and 2.5 as the benefits identified above outweigh the costs. Council considers that the selected manner of achieving the objectives is efficient because the costs have been minimised where possible and are necessary consequences of achieving the objective. The benefits mean that overall the rule framework is as efficient as it can be. The activity status table clearly signals to the community and landowners which activities are appropriate and which activities require close inspection in terms of potential effects with regards to natural hazards. This is an effective approach in achieving the objective and minimising the risk to life and property as a result of natural hazards. Standards Benefits        

   

Clear expectation of compliance with the standards. Encourages development that meets the standards (usually as a permitted or controlled activity) Lessens the risk to life and property in accordance with Objectives 2.3(c) and 2.5. Ensures buildings are not sited within the Stream Corridor Hazard Area in accordance with Policies 9.11 and 9.12. Ensures the floor level of any new building in the ponding hazard area is constructed above the 1 in 100 year flood event level in accordance with Policy 9.10. Avoids earthworks in overflow paths, residual overflow paths, ponding areas and stream or river corridors in accordance with Policy 9.12. Ensures fences do not impede the free flow of water. All flood protection works must be carried out by either Wellington Regional Council, Kāpiti Coast District Council or Department of Conservation. This ensures that any flood protection works is for the benefit of the community as a whole. Ensures hydraulic neutrality is achieved. This is an effective means of avoiding adverse effects on and managing stormwater. Provides clarity as to the variables affecting the status of buildings in the Fault Avoidance Area including recurrence intervals, building importance and fault complexity. This effectively implements Policy 9.14. In the case of subdivision, ensures that a building site can be located outside of the Fault Avoidance Area. Enables development close to the Fault Avoidance Areas in certain circumstances. This aligns with Policy 9.14.

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  

Natural Hazards

Ensures geotechnical information is provided by a suitably qualified person. This enables the risk of building in that particular location to be assessed in terms of the Fault Avoidance Area. Clarifies the scale of acceptable extensions to buildings in an unambiguous manner Sets out the requirement for a report from an appropriately qualified and experienced person to demonstrate that structures will not be likely to nor contribute to damage arising from slope instability.

Costs    

Places restrictions on activities and structures May create additional cost to comply with the standards. Places restrictions on how buildings are to be designed. May constrain the maximum development possible on any particular site.

These rules (standards) will be efficient to achieve Objective 2.3(c) and 2.5 as the benefits identified above outweigh the costs. Council considers that the selected manner of achieving the objectives is efficient because the costs have been minimised where possible and are necessary consequences of achieving the objective. The benefits mean that overall the rule framework is as efficient as it can be. Compliance with the standards in terms of Permitted activities ensures there is minimised risk to life and property from natural hazard events. This is an effective approach in achieving the objectives and protecting the community from the risk of natural hazards. Development Control Areas on District Plan Maps As outlined in Policy 9.1, the extent of flood, earthquake fault rupture, coastal erosion, river erosion and slope instability hazard modelling has been used to identify development control areas on the District Plan maps. The main purpose of this is to provide certainty to property owners and effectively enable Council to implement the Policies in the Natural Hazards chapter. Benefits        

Ensures hazards are identified Minimises the loss of life and damage to property in high risk areas Provides clarity and certainty to the community through identifying hazards on the District Plan maps Enables activities, development and subdivision to be controlled in areas subject to hazards to lessen the risk to people and the community. Enables efficient forward planning for these areas to ensure additional assets and people are not put at risk Ensures hazards are identified Quantifies the risk rather than a blanket approach Identifies where risks from natural hazards are most significant

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Costs     

Restricts development in these areas May reduce the economic value of sites in these overlays There will be inherent inaccuracies – some properties will be incorrectly identified whilst others may be left out Does not quantify the risk e.g. the frequency, magnitude or duration of risk Based on theoretical models which may not accurately forecast the future

This method will be efficient to achieve Objective 2.3(c) and 2.5 as the benefits identified above outweigh the costs. Council considers that the selected manner of achieving the objectives is efficient because the costs have been minimised where possible and are necessary consequences of achieving the objective. The benefits mean that overall the rule framework is as efficient as it can be. Mapping areas most susceptible to risk from natural hazard events is an effective means of firstly identifying the risk and secondly enabling these areas to be managed to minimise risk to life and property. This is an effective approach in achieving the objectives and protecting the community from the risk of natural hazards.

6.2 What are the risks of acting or not acting if information gaps exist? Council considers there is sufficient information regarding the subject matter of the above rules that support the objectives and policies relating to natural hazards. The risks of not acting far outweigh the risks of establishing methods to minimise the risk to life and property. Not acting would increase the risk to the community from natural hazard events and would not achieve Objectives 2.3(c) and 2.5.  

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7 CONCLUSION The protection of health and safety of the community and property from the risk of natural hazards is critical to the social, cultural and economic well-being of the present and future community of the District. The District is at risk from a number of natural hazards as follows. 1. Flooding The District’s physical landscape presents varying levels of flood risk to settlements (particularly on the coastal plain). During high rainfall events flooding can occur within minutes of the event and can result in significant damage. Property and structures located in the river /stream corridor, flood erosion areas, flood storage areas and overflow paths (including residual overflow paths) are more susceptible to damage from flooding. 2. Fault Rupture A fault rupture has the potential to cause significant damage to buildings, structures and life without warning. A large earthquake could cause a fault rupture which may result in significant vertical and/or horizontal movement of land. It is likely that buildings or structures sited over a fault would suffer considerable damage. 3. Liquefaction There is potential for liquefaction to result in land subsidence across the district during a large distant earthquake event. Future observed liquefaction events in these areas may be associated with loose sand deposits within the floodplain deposits. There is also potential for lateral spread of the Waikanae and Ōtaki river banks. During a large earthquake on the Wellington Fault or one of the faults in the district the likelihood of liquefaction is more varied than a distant earthquake event and will depend on the ground conditions at a particular site. 4. Slope Failure The Kāpiti area has significant earthquake induced slope failure hazards particularly in the southern and south-eastern parts of the district. For example between Pukerua Bay and Paekākāriki, the terrain is steep and slopes have a very high susceptibility to slope failure which could sever transport links to Wellington. 5. Tsunami The District is considered to have a very low level risk from a damaging or catastrophic tsunami. The Kāpiti Coast has the lowest risk in the Wellington Region of a major or catastrophic tsunami, with earthquakes near the Solomon Islands posing the highest degree of risk. The risk for the Kāpiti Coast has been modelled using a distant pacific sourced 500 year event which results in a wave height of 2.5 – 3 metres. This has been included in tsunami evacuation areas which are not part of this plan. 6. Slope instability Landslips pose a significant risk not only to existing properties within the district but also to regional and nationally significant infrastructure including transport routes such as SH1 and the rail corridor. In the southern and south-eastern parts of the district the terrain is steep and slopes have a very high susceptibility to slope failure. 7. Fire The nature of the Kāpiti Coast climate varies greatly, resulting in the District developing a high fire danger, sometimes earlier than the rest of the Wellington s32 Report – Natural Hazards  

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Region. Some areas of the district are more prone to wildfire than others. The coastal dune area is very quick to dry out following periods of low rainfall or sustained northwest winds. The lowland hills of the Tararua Ranges are also being increasingly planted in exotic pine which increases the fire risk. The wildfire hazard (risk to life and property) has increased due to increasing development in these high risk wildfire zones. Climate change projections pose an additional wildfire threat with increased propensity for drought and stronger or more sustained wind events. The proposed Natural Hazards chapter recognises the potential for natural hazards to threaten life and property and seeks to minimise the risk. Proposed Objective 2.3(c) and 2.5 both seek to ensure the safety and resilience of communities by avoiding exposure to the risk of natural hazards. This direction is implemented through policies which provide mechanisms for achieving the objectives. Examples of this include Policy 9.3 which avoids locating new subdivision, land use and activities in high risk hazard prone areas. The policy achieves this through mapping those areas on the District Plan maps. Rules then ensure this is implemented through activity classification and standards. For example subdivision or development on land subject to two or more high risk natural hazards is a non complying activity. This approach gives effect to the direction given through the regional policy statement. The proposed Natural Hazards chapter is considered to provide clear objectives that minimise the risk of natural hazards through managing development. This in turn enables an efficient and effective framework of policies and rules to be established. This approach enables the Council to fulfil its statutory obligations of the RMA in a way that provides for the social, economic and cultural well being of current and future generations. This sentiment is reflected in Objectives 2.3(c) and 2.5 and will be achieved through effective and efficient policies, rules and methods.

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