10/749 implementation of coastal flood hazard overlays ... · pdf fileimplementation of...

10/749

Subject:Implementation of Coastal Flood Hazard Overlays with Rules for Land Use

Prepared by: Katrin Markull (Intern Natural Resources Policy)

Meeting Date: 8 December 2010

Report to ENVIRONMENT & POLICY Committee for decision

SUMMARY

During the last few years, Coastal Hazard Zones have been developed for various areas in the Gisborne District. In particular, these zones address erosion and landslip hazards. The Coastal Flood Hazard Zones, which were calculated for Tolaga Bay, Anaura Bay and Muriwai, have not been incorporated into the plans yet. This report proposes the incorporation of the Coastal Flood Hazard Overlay and the associated rules for land use, development and subdivision into the Part Operative Combined Regional Land and District Plan (District Plan) and the Proposed Regional Coastal Environment Plan (Coastal Plan) to mitigate the adverse effects of coastal flooding and promote more comprehensive and consistent decision-making for resource consent assessments.

RECOMMENDATIONS

That the Committee

1. receives the report

2. Recommends that Council

a. adopts the attached Plan Change Analysis Report as the evaluation required under Section 32 of the Resource Management Act 1991

b. notifies the proposed plan change to the Part-Operative Combined Regional Land and District Plan and the proposed variation to the Proposed Regional Coastal Environment Plan

c. endorses further research into the calculation of a storm-wave based Coastal Flood Hazard Zone for Tokomaru Bay.

Katrin Markull Yvette Kinsella Hans van KregtenIntern Team Manager Group Manager Natural Resources Policy Natural Resources Policy Environment and Policy

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1. BACKGROUND

In 1994 Council commissioned Dr Jeremy Gibb (Coastal Management Consultancy Limited) to assess the risk of different natural coastal hazards in the Gisborne District. In this research 112 locations were evaluated based on their sensitivity to natural coastal hazards and a broad-brushed map of “Areas Sensitive to Coastal Hazards” was developed. As a second step, a detailed assessment of several medium to high priority areas was made, resulting in the development of Coastal Hazard Zones for erosion and landslip risks. The zones are divided into extreme, high and moderate risk as well as a buffer zone and are incorporated as overlays into the District’s plans. Rules for these overlays have been developed and implemented in the Regional Coastal Environment Plan and the Combined Regional Land and District Plan.

For three of the areas, namely Muriwai, Tolaga Bay and Anaura Bay, Coastal Flood Hazard Zones were calculated; based mainly on historic data of run up levels. For these zones no rules have yet been implemented. As the effects of flooding are very different to those of erosion and landslips, where land disappears after a hazardous event, it is proposed to introduce specific rules to mitigate against the risk of coastal flooding. The objective of these rules is to improve protection from coastal flooding for new buildings while at the same time not unnecessarily prohibiting land use in the overlay.

The objective of the proposed project is therefore the incorporation of the Coastal Flood Hazard Overlay and rules concerning land use, subdivision and development into the Coastal Plan and the District Plan. The core of the new rules would be the implementation of minimum floor heights for habitable buildings. This is similar to the overlays for flooding from rivers which are already incorporated into the District Plan.

All relevant information for the proposed plan change is readily available and no new research needs to be conducted.

The new rules would help achieve objectives stated in the District Plan and the Regional Policy Statement:

“1. A pattern of human settlement that:

• provides a high level of personal safety from natural hazards for its inhabitants;

• avoids or mitigates the risk to property and infrastructure from natural hazards; and

• does not accelerate or worsen the adverse effects of natural hazards upon the natural and physical environment.

2. A community informed of the potential natural hazards of the District.

3. The protection of natural features that could lessen the impact of natural hazards.”

2. DISCUSSION and OPTIONS

Even though calculated by an experienced practitioner, the Coastal Flood Hazard Zones incorporate a level of uncertainty, as natural hazards and the effects and nature of climate change are not fully predictable. However, the zones do give an indication as to where the risk of coastal inundation is highest and where development is most at risk from flooding.

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Dr Gibb developed zones based on both historic tsunami and storm wave levels. Tsunami have a significantly different nature with much higher energy levels and a significantly longer return period. To include tsunami risk in land use planning, it is considered that more detailed computer-based modelling data is required. Currently, data of this nature is not available for the Coastal Flood Hazard Zones. Therefore it is proposed that the zones and rules are based on flooding from storm wave run up only. For the Coastal Flood Hazard Zones in Tolaga Bay, Anaura Bay and Muriwai, the historic storm wave run up levels are in any case higher than the historic tsunami run up levels identified by Dr Gibb. However, another Coastal Flood Hazard Zone was calculated for Tokomaru Bay, where the historic tsunami levels are higher than the historic storm wave levels. Therefore, it is recommended that a new assessment of the Coastal Flood Hazard Zone in Tokomaru Bay be conducted, taking into account storm wave flooding risk only.

While the development and implementation of regional rules concerning the development, land use and subdivision of Coastal Flood Hazard Zones is the main objective of this project, other measures for the mitigation of the adverse effects of coastal flooding are taken into account and evaluated as well. These measures include communication and education, coastal protection works and financial mechanisms (rates relief) which might assist in mitigating adverse effects of coastal flooding. The assessment of options (see Appendix) shows that the implementation of regional rules is an effective and efficient measure for the overall mitigation of adverse effects of coastal flooding to buildings.

A rates relief policy for land owners who move their dwellings out of the Coastal Flood Hazard Zones is possible but might imply significant losses in rates. Overall the effectiveness and efficiency of this option is considered questionable.

Coastal protection works would not be cost effective due to the affected areas being large as well as sparsely-populated. In addition is the effectiveness of protection works questionable and often only protection for less than 50 years can be reached. Hard engineering techniques in particular often have adverse effects on ecological and amenity values. Coastal protection works might also be inconsistent with several policy statements and plans.

Communication and education can be advantageous as a supportive technique for the proposed rules. The associated costs are relatively small and the effects can be significant. However, communication and education are usually not effective enough to be implemented as a self-standing measure.

The implementation of a Coastal Flood Hazard overlay and associated rules for managing land use is an effective and efficient measure to mitigate the adverse effects of coastal flooding. The costs are by far outweighed by the benefits and the plan change would be consistent with all relevant legislation.

Currently, decisions on resource consents in the Coastal Flood Hazard Zones are not based on defined zones and adopted standards but include a degree of subjectivity and opinion. The development of rules would improve this situation and lead to more consistent, objective decision-making in the future. The anticipated result is a subdivision and land use policy that avoids the need for new protection works and offers a precautionary approach without unduly affecting development of the areas. Decisions would be consistent over all Coastal Flood Hazard Zones in the Gisborne District and over time even with changes in staff.

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The proposed rules include permitting residential buildings that meet certain minimum floor heights while prohibiting residential buildings that do not meet these floor heights. This way future residential buildings will be safer from coastal flooding.

Another option considered was to make residential buildings a restricted discretionary activity. That would mean any application for a building within the Coastal Flood Hazard Overlay not meeting minimum floor heights would be subject to Council discretion on a case by case basis. Land owners would be able to apply for resource consent even if the proposed building did not meet the floor height conditions. Officers suggest this option is less desirable. Setting minimum floor heights is the standard approach to managing flood risk in our RMA plans. There are limited effective alternatives to protect property. Alternatives rely on expensive flood control schemes and might restrict or divert the passage of floodwaters, possibly having a negative impact on adjacent landowners.

It is therefore recommended to implement the first proposal which is described in the Appendix.

The identification of hazard zones is an objective of several national and regional plans. The plan change would therefore lead to more compliance with all relevant legislation as the available data on hazard zones would be incorporated into Council’s plans.

3. SIGNIFICANCE

No decisions of significance under Council’s significance policy are addressed in this report.

4. CONSULTATION

The preparation of this plan change was conducted in accordance with Schedule 1 of the Resource Management Act 1991 which describes the requirements for preparing, changing and reviewing policy statements and plans including consultation requirements.

The community’s concerns and ideas to protect against coastal flooding in the defined CFHZ in the future have been determined through pre-consultation.

Public meetings were organised for all communities. Invitation letters were sent to land owners and all relevant iwi authorities. The general public was invited through posters, flyers, school newsletters and radio announcements. The meetings showed that a large proportion of the community is aware of the risk and interested in the topic. Members of the communities that have already been subject to minimum floor heights for buildings mentioned that it did not add any extra costs and they were happy to build higher if this leads to a safer home.

5. LEGAL

This project is to give effect to objectives in the Regional Policy Statement and the District Plan that aim to avoid and mitigate hazard risk.

The development of rules would meet the relevant policies in the Coastal Plan: Policy 3.8.4A “The Council will adopt a two-tiered assessment of areas prone to natural hazards associated with coastal erosion, storm surge inundation and slips. These assessments will be incorporated into the Regional Coastal Environment Plan and the District Plan for the Gisborne District.”

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Developing rules and implementing the zones would be consistent with the New Zealand Coastal Policy Statement 1994:

Policy 3.4.1 “Local authority policy statements and plans should identify areas in the coastal environment where natural hazards exist.”

The rules would also be consistent with the New Zealand Coastal Policy Statement 2010: Policy 24: “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 for being affected.”

The development of rules would meet the relevant policies and methods of the Regional Policy Statement:

Policy 2.3.2 (1) “To encourage and facilitate changes, over time, to patterns of human settlement, development and activities which are not affected by natural hazards and which do not induce or worsen the impacts of natural hazards.”

Method 2.3.3 (6) “Adopt methods, including rules, in district and regional plans controlling development in areas affected or potentially affected by natural hazards that prevent, restrict or require special design or precautions, as appropriate.”

The proposed rules would go through the prescribed Plan Changes/Plan Variation process to be implemented in the Proposed Regional Coastal Environment Plan and the Part Operative Combined Regional Land & District Plan.

6. APPENDICES

1 Plan Change Analysis Report

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Plan Change Analysis Report (Section 32 Report)

Proposed Variation 14 to the

Proposed Regional Coastal Environment Plan

Proposed Plan Change 43 to the

Part-operative Combined Regional Land and District Plan

November 2010

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Table of Contents

1. Executive Summary.................................................................................................... 8 2. Introduction ................................................................................................................ 9

2.1. Problem Description........................................................................................... 9 2.2. Reasons for the Proposed Changes.................................................................. 9 2.3. The Proposed Changes .................................................................................... 10 2.4. Public Participation .......................................................................................... 10 2.5. Plan Change Process ....................................................................................... 11 2.6. Report Layout ................................................................................................... 11

3. Background............................................................................................................... 12 3.1. Coastal Flooding ............................................................................................... 12 3.2. Coastal Hazard Planning in the Gisborne District .......................................... 13 3.3. The Assessment of the Coastal Flood Hazard Zones .................................... 13

4. Analysis of Options ................................................................................................... 15 4.1. Statutory and Policy Framework...................................................................... 15

4.1.1. Introduction ........................................................................................... 15 4.1.2. Relevant Functions of Council (section 30 and 31) .............................. 16 4.1.3. New Zealand Coastal Policy Statement 2010........................................ 16 4.1.4. Regional Policy Statement....................................................................... 17 4.1.5. Part Operative Combined Regional Land and District Plan for the Gisborne District 18 4.1.6. Proposed Regional Coastal Environment Plan....................................... 20

4.2. Objectives ......................................................................................................... 22 4.3. Analysis of Proposed Changes and Alternative Measures ............................ 23

4.3.1. Introduction .............................................................................................. 23 4.3.2. Outcomes of the Community Consultation Meetings ............................ 23 4.3.3. Analysis of Benefits and Costs ................................................................ 25

5. Conclusion ................................................................................................................ 29 6. Recommendations ................................................................................................... 30

6.1. The Proposed Plan Changes............................................................................ 30 6.2. General Recommendations ............................................................................. 33

Reference List................................................................................................................... 34 Appendices ....................................................................................................................... 35 Appendix 1: Variation/Plan Changes Process ................................................................ 36 Appendix 2: Maps of the Coastal Flood Hazard Zones .................................................. 37 Appendix 3: Minutes from the Public Meetings ............................................................. 41

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1. Executive Summary In the last few years, Dr Jeremy Gibb was commissioned by Gisborne District Council to assess the sensitivity of several locations of Gisborne’s coast to natural hazards. As a result, Dr Gibb calculated coastal hazard zones for landslips, erosion and flooding. The hazard zones for landslip and erosion were incorporated into the district’s plans while the coastal flooding zones have not been incorporated yet. The Coastal Flood Hazard Zones are located in Muriwai, Anaura Bay and Tolaga Bay and are based on historic storm wave run-up levels. This report proposes to include a Coastal Flood Hazard Overlay with rules for land use into the Part Operative Combined Regional Land and District Plan (District Plan) and the Proposed Regional Coastal Environment Plan (Coastal Plan). The inclusion of a mapped overlay will give clarity to Council staff and the public as to where there is a coastal flooding risk. Rules for managing land use in the flooding zones were developed following consultation with affected communities. The proposed rules would help to guide appropriate land use and minimise adverse effects on land owners and communities. Buildings in the Coastal Flood Hazard Zones would be required to have minimum floor heights for habitable and residential rooms to allow water to flow underneath or past the buildings without risk of injury. In the past, consents in these zones have been decided on a case-by-case manner. Clear rules in the plans will lead to more consistent decision-making and greater certainty for land owners. The proposed changes are consistent with all relevant legislation and help reach the objective of the Proposed Regional Coastal Environment Plan of developing human settlements that avoid or mitigate the risk to property and infrastructure from natural hazards. An analysis of benefits and costs assessed alternative measures for reaching this objective, including not doing anything, coastal protection works, communication and education and a relocation rates relief. This assessment showed that the incorporation of the zones and rules in the district’s plans is the most appropriate measure. It can be supported by communication and education which is also consistent with all relevant legislation and relatively low costs.

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2. Introduction

2.1. Problem Description Coastal flooding is a significant natural hazard in the Gisborne District and it can form a threat to lives and destroy buildings and infrastructure. To minimise the adverse effects on communities of coastal flooding, different measures can be taken. One measure is to minimise coastal flood risk through land use planning controls. Research has been conducted to find out where there is a higher risk for coastal flooding, coastal erosion and landslips in the Gisborne District and resulted in the calculation of Coastal Hazard Zones. With this knowledge, land use planning can be adapted to the risk of the different coastal hazards, including coastal flooding. The purpose of this report is to develop an approach to mitigating the effects of coastal flooding in the designated Coastal Flood Hazard Zones, calculated by Dr Jeremy Gibb for the Gisborne District Council. The result of the project will be a set of rules to minimise possible adverse effects of inundations. These rules will help manage land use, subdivision and development in the defined Coastal Flood Hazard Zones. The Combined Regional Land & District Plan for Gisborne has set similar rules for flooding from rivers as well as the coastal erosion and landslip hazard zones. However, a set of policies for coastal flooding has not been developed so far. Currently, decisions on land use, subdivision and development in Coastal Flood Hazard Zones are made case-by-case which may lead to inconsistency. Defined rules would give the decision-makers a stronger legal support for their decisions and help reaching consistency. The rules should be chosen carefully to find a balance between a precautionary approach and preventing the implementation of too strict regulations which might adversely effect economic growth and decrease the livelihood of the region. Other measures will be discussed to support the new rules in their effectiveness for mitigating the adverse effects of coastal inundation. These measures will include coastal protection works, communication and education and a rates relief policy and will be compared in an analysis of benefits and costs (see Chapter 4.3.3). Apart from the growing anthropogenic pressure on the coastline leading to the need of carefully developed measures, climate change is expected to increase the risk of natural coastal hazards. Even though climate change will not lead to new natural coastal hazards, it is likely to increase the magnitude and frequency of existing hazards by influencing the hazards’ drivers (Ministry for the Environment 2008). Coastal flooding might be influenced by an expected rise in sea level and changing wind patterns. Therefore, climate change has to be taken into account when planning long-term developments such as in this project, where the results may influence the development of buildings which usually have a life span of more than 100 years.

2.2. Reasons for the Proposed Changes The main reason for the proposed land use rules is the need for more consistent decision-making on land use in the Coastal Flood Hazard Zones to ensure new buildings are safer from being damaged by coastal flooding. This complies with an objective stated in the Proposed Regional Coastal Environment Plan:

“1. A pattern of human settlement that: • provides a high level of personal safety from natural hazards for its inhabitants; • avoids or mitigates the risk to property and infrastructure from natural hazards; and • does not accelerate or worsen the adverse effects of natural hazards upon the natural and physical environment. 2. A community informed of the potential natural hazards of the District. 3. The protection of natural features that could lessen the impact of natural hazards.”

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The current approach to managing the Coastal Flood Hazard risk is inconsistent with policies and plans of Council as the knowledge of the risk areas has not been incorporated in planning documents.

2.3. The Proposed Changes This report proposes the development of land use, subdivision and development rules for a Coastal Flood Hazard Overlay. In order to make future developments less prone to damage through coastal flooding, minimum floor heights could be implemented. Through these minimum floor heights, the water from a flood event could flow underneath or past residential buildings without damaging the buildings. Permitted activities in the Coastal Flood Hazard Overlays would include all internal alterations of residential buildings, habitual buildings, decks and pergolas attached to an existing residential building, accessory buildings associated with a residential dwelling in the area and the construction, addition to or alterations to the upper floor levels of any existing residential or habitable buildings. The construction or relocation of residential and habitable buildings as well as the addition to or alteration of these buildings is permitted if the designated minimum floor heights are met in order to be safe from flooding. The minimum floor heights depend on historic storm wave run-up levels and vary between the three coastal flooding zones. If accessory buildings or non-habitable rooms are converted into residential buildings and/or habitable rooms, these must also have the minimum floor heights as new residential buildings. Discretionary activities include and earthworks that alter the ground level and any new roads, road alterations or shape corrections that alter the pavement level. Whether a consent will be granted will depend on whether the activity restricts or diverts floodwaters and whether lives or property would be endangered in the event of flooding. Prohibited is the construction, addition to or relocation of residential and habitable buildings that do not meet the specified floor heights and the conversion of accessory buildings into residential buildings if these do not meet the specified floor heights. The exact rules can be found in Chapter 6.1. In order for the rules to be implemented, the zonation also has to be incorporated into the district’s plans.

2.4. Public Participation The proposed changes were prepared in accordance with the First Schedule of the Resource Management Act. The First Schedule states the requirements for preparing, changing and reviewing policy statements and plans including consultation requirements. A diagram of the complete plan change process as described by Schedule 1 of the Resource Management Act can be found in Appendix 1. The preparation of this plan change was conducted in accordance with Schedule 1. The community’s concerns and ideas to reach the objective of more safety from coastal flooding in the defined CFHZ in the future have been determined through pre-consultation. Public meetings were organised for all communities. Invitation letters were sent to land owners in the proposed Coastal Flood Hazard Overlay and relevant iwi authorities. The meetings included an introduction into coastal flooding, the zones and Council’s ideas for managing these zones, as well as a discussion of these ideas. Community members who were unable to attend the meetings were invited to contact Council should they have any questions or comments. Should the committee agree with the proposed changes will a plan change process be initiated in which the communities have an opportunity to make formal submissions to the proposed changes as described in Chapter 2.5.

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2.5. Plan Change Process The proposed rules developed in this report will go through a Plan Changes/Plan Variation Process (see Appendix 1 for a complete diagram of the process), should the Environment & Policy Committee agree with the proposal. Council will publicly notify the proposed changes and the public can then make written submissions on the changes. Council will prepare a summary of the submissions and send it to all people who made submissions. The public can then make further submissions to this summary. Council will analyse all submissions and if required prepare a report for a pre-hearing meeting in which issues can be clarified and possibly solved. A hearing panel will hear the submissions and recommend to Council how the proposed changes should be dealt with, based on the submissions and the report prepared by Council. After the decision is made, Council notifies the public and submitters can make an appeal if they disagree with the decision. These appeals can be resolved via mediation or Court hearings at the Environment Court. The proposed changes will become operative once all appeals are resolved. If approved, the rules proposed in this report will be included in the Proposed Regional Coastal Environment Plan and the Part-Operative Combined Regional Land and District Plan for the Gisborne Region. The Combined Regional Land & District Plan already features policies for several other natural zones and hazards such as coastal erosion and flooding from rivers. However, the coastal flooding section currently does not include any rules.

2.6. Report Layout This plan change analysis will first of all give some background information about the Coastal Flood Hazard Zones and coastal flooding. A description of the statutory and policy framework in which the rules are proposed will be given. The proposed rules and alternative measures will be assessed in a cost-benefits analysis, also taking into account effectiveness and efficiency, and a conclusion with recommendations will be given. The proposed plan change can be found in Chapter 6.1. Maps showing the zones are included in Appendix 2.

3. Background

3.1. Coastal Flooding Coastal flooding is the overflow of water at the coastline, which can submerge land and flood developed areas and lead to significant adverse economic effects and form a threat to human life and property. There are two main causes of coastal flooding: tide surges and tsunami. Due to the unpredictability of tsunami and insufficient data being available, this report will only take into account the flooding risk from tide surges. Tide surges are temporary elevations in sea level during adverse storm conditions (Bell & Gorman 2003). They can develop as a combination of different factors, which lead to a rise in local sea level near the coast. These factors include astronomical tides, strong on-shore winds and waves and a barometric pressure set-up (Gibb 1995). When all of these factors occur at the same time is there a risk of coastal inundation (see Figure 1). Astronomical tides are “movements of the oceans set up by the gravitational effects of the moon and the sun in relation to the earth” (Charles & Bird 2008). During high tides, water levels at the coast are elevated which can become a threat if high tides occur at the same time as a strong on-shore storm.

A very low pressure can lead to a vacuum effect over the ocean which raises the sea-level to compensate for the drop in air pressure. The bigger the difference between barometric pressure and mean atmospheric pressure, the larger the effect of barometric pressure set-up can be (Bell & Gorman 2003).

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On-shore winds can force the water towards the coastline, leading to an increased local sea level.

Waves can affect inundation

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WatdamwheEspporfurtIn preCoaevecomesp

gure 1: The principle of storm surges (Ministry for the Environment 2008

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in three ways: by wave set-(increased water level landward of the broken waves), wave run-up (waves running up the shore hey break and after they have broken) and overtopping (waves that run over barriers which leads ater invading the land behind the barrier) (Ministry for the Environment 2008). er flooding the land can have adverse effects on several factors. Firstly, buildings can be aged, leading to large financial and social drawbacks. Recreational activities can be vulnerable, re they are located close to the shoreline or include beaches that might be prone to erosion. ecially Port areas can be vulnerable to coastal flooding due to their position at the coast and ts being relatively low-lying. Materials at ports such as logs can be carried away by the water and her augment the destructive effect of the inundation (Wang et al. 2009). extreme cases coastal inundation can also form a threat to human life, especially if no cautionary measures such as evacuation are taken. stal inundation can cause severe erosion, which makes the coast even more sensitive to flooding nts in the future as it damages the natural coastal defences. Gisborne is, for a large part, posed of soft materials, which are especially prone to erosion. Small gaps in sand dunes are

ecially vulnerable and can be “washed out” by flood events, increasing the sizes of the gaps.

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Coastal inundations can also threaten saltwater contamination of freshwater environments (Wang et al. 2009). The longer the saltwater covers the land, the more extreme the contamination effects can be for agriculture and other forms of primary production. Water will cover land the longest where it can not easily flow away. This is the case in the designated Coastal Flood Hazard Overlay, where there are low basins lying behind relatively shallow dune crests. In the basins, water can be trapped, flowing into the ground only slowly, leaving the land inundated for a long time.

3.2. Coastal Hazard Planning in the Gisborne District In 1994 a coastal hazard assessment programme was established in the Gisborne District by Dr Jeremy Gibb, assessing the sensitivity of Gisborne’s coast to coastal hazards, namely erosion, landslips and coastal flooding. An initial assessment looked at all areas sensitive to coastal hazards (ASCH) and identified the sensitivity of 112 points along the coastline. The assessment was based on a Coastal Sensitivity index (CSI), taking into account factors such as elevation, storm-wave run up, tsunami run up, gradient, lithology, landform and short-and long-term fluctuations. Based on these criteria, all points were ranked into five classes, indicating very low, low, medium, high or very high risk areas (Gisborne District Council, 2006). In the next step, a more detailed study assessed the sensitivity of medium to high priority areas. These areas included Waipaoa River Mouth to Makorori Point (1995), Tolaga Bay and Anaura Bay (1998), Wainui Beach (1995, review 2001), Southern Poverty Bay (2004) and Tokomaru Bay (2008), for which coastal hazard zones were developed. Gibb calculated the coastal hazard zones for the Gisborne District and defined a coastal hazard zone as “land that is, or is likely to be subject to the effects of coastal hazards over a defined hazard assessment period. For New Zealand, that period has been standardized as 100 years since its endorsement by the National Water and Soil Conservation Authority in March 1981” (Gibb, 2004). Gibb developed different hazard zones for coastal erosion (CEHZ), landslips (CLHZ) and coastal flooding (CFHZ). The zones for erosion and landslip risk have been incorporated into the Coastal Plan and in the District Plan as Coastal Hazard Overlays. The Coastal Flood Hazard Zones have not been implemented in the district’s plans and policies yet.

3.3. The Assessment of the Coastal Flood Hazard Zones Dr Gibb defines a coastal flood hazard zone as “the area of coastal land subject to actual and potential inundation during overtopping of the crest of the foredune from storm wave and tsunami wave runup” (Gibb, 1995). Four coastal flood hazard zones have been identified in the Gisborne District. Maps for these zones can be found in Appendix 2. Tolaga Bay In Tolaga Bay the dune crest is around 2-2.5 m aMSL (above mean sea level) at the northern end of the beach and around 3-5 m aMSL at the southern end. Behind the dunes there is a shallow basin (2-2.5 m aMSL) that leads to the Uawa River (Gibb, 1998). This shallow basin can be flooded during coastal inundation. In addition there is a risk of flooding from the Uawa River as well. Gibb recommends a 3 m contour line as the landward limit of the CFHZ in Tolaga Bay. This is based on the above described heights of the dune crest and the likely heights of tsunami and storm wave run-up. For a tsunami, Gibb adapted a run-up height of 4-6 m aMSL which is the expected height of a tsunami generated by a local earthquake which has a relatively high probability due to the active tectonic situation off the east coast (Gibb, 1998). For storm wave run-up, Gibb used the maximum historic run-up level generated during a Class 4 Tropical Cyclone, which was 6-7 m aMSL (Gibb, 1998). The 3 m aMSL line was adapted as it represents the area likely to be flooded during an extreme event in which the water would inundate the land for a longer period. Higher areas might be flooded for a short time but the water would be drained by the river relatively soon.

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Anaura Bay The dune crest of Anaura Bay is around 3 m aMSL, with the land behind it rising to 4-8 m aMSL, apart from the northern end where the land is 3.5-4 m aMSL. Five houses in Anaura Bay are located in a shallow basin, protected by a 3.5-4 m aMSL dune crest. The land in which the Anaura Bay motor camp was built is 2.5-3 m aMSL, forming a basin behind the 3-3.5 m aMSL high dune crest (Gibb, 1998). This basin is also at risk of being flooded from the sea, with water being trapped in the basin for a longer period of time. For Anaura Bay, historic tsunami run up levels of 4-6 m and historic storm wave run up levels of 5-7 m were used. Gibb recommended a landward boundary of the contour line of 4 m aMSL north of the Waipare Stream and 3.5 m aMSL south of the stream. Within this zone, land would be flooded during extreme storm wave or tsunami events (Gibb, 1998). Muriwai For Muriwai, the Coastal Flood Hazard Zone calculated by Gibb is composed of two components: The Flood Velocity Zone and the Flood Ponding Zone. The Flood Velocity Zone is the zone subject to wave overtopping and includes the Muriwai sand spit, the mouth areas of Wherowhero Creek and its lower-lying areas bordering the estuary, the low-lying areas adjacent to the Karaua Stream mouth and the right bank of the Waipaoa River and the Orongo Beach foredune. The Flood Ponding Zone is adjacent to the Flood Velocity Zone and covers the area subject to temporary inundation from storm wave or tsunami run-up. The zone includes all land seaward of the Muriwai coastal plain lying between 1-3 m aMSL so the CFHZ contour line is the 3 m aMSL line (Gibb, 2004). This elevation was developed by adding up the historic tsunami run up levels (2.3 m in 1947)/ historic storm surge run up levels (2-3 m), a projection of global sea level rise (0.4 m by 2100) and a safety factor (0.3 m) to account for uncertainties in the elevations (Gibb, 2004). Tokomaru Bay For Tokomaru Bay, two different Coastal Flood Hazard Zones have been calculated, one indicating the 2008 CFHZ and one indicating the 2108 CFHZ, taking the expected sea-level rise into account. Both zones are based on historic storm wave and tsunami run-up levels. The 2008 CFHZ covers the area seaward of the 4.5 m aMSL contour line and is based on historic storm wave run-up levels ( 3.5-5 m a MSL during Tropical Cyclone Bernie in 1982 which has an Annual Exceedence Probability of 2 %) and tsunami run-up levels during events between 1947 and 1960 (4 and 4.5-5.5 m respectively) (Gibb, 2008). For the 2108 CFHZ Dr Gibb used the contour line of 4.5 m aMSL for the 2008 CFHZ as a basis and added an expected sea-level rise of 0.8 m and a safety factor of 0.2 m, recommending a 5.5 m aMSL contour line for the 2108 CFHZ (Gibb, 2008). As the tsunami run up levels for Tokomaru Bay are higher than the historic storm wave run up levels, it is recommended that a new calculation of the Coastal Flood Hazard Zone in Tokomaru Bay is conducted for storm wave flooding only. The quality of the data currently available is not sufficient to base land use planning on tsunami hazards. In the three other regions, historic storm wave run up levels were higher than historic tsunami run up levels. Therefore, these zones can be seen as zones indicating purely the risk of storm wave flooding, excluding tsunami. In order to integrate tsunami inundation risk into land use planning, more extensive research will have to be conducted and computer-based models will have to be used. For the three Coastal Flood Hazard Zones in Tolaga Bay, Muriwai and Anaura Bay rules concerning subdivision, use and development will be proposed to mitigate the damage inundations can have on future developments. Maps showing the Coastal Flood Hazard Zones can be found in Appendix 2.

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4. Analysis of Options

4.1. Statutory and Policy Framework

4.1.1. Introduction The Resource Management Act sets rules and responsibilities for councils. Section 66 of the Resource Management Act states matters that must be considered by regional council when preparing or changing a regional plan. Section 74 states matters that must be considered by territorial authority when preparing or changing a district plan. As a unitary authority, proposing a change to the District Plan and a variation to the Coastal Plan, the Gisborne District Council has to comply with both of these sections. This means that when preparing the plan change, Council must have regard to

• Its functions under section 30 and 31 (see Chapter 4.1.2) • Its duty under section 32 (this report) • Any proposed regional policy statement • Management plans and strategies prepared under other Acts • The Crown’s interest in land of the Crown in the coastal marine area

The proposed changes have to be consistent with any relevant policies from the New Zealand Coastal Policy Statement. The Resource Management Act also requires local authority to conduct an assessment of alternatives, benefits and costs when proposing a change to a policy statement or a plan. This assessment must examine

• the extent to which each objective is the most appropriate way to achieve the purpose of the Resource Management Act; and

• whether, having regard to their efficiency and effectiveness, the policies, rules, or other methods are the most appropriate for achieving the objectives.

The Resource Management Act also states that further evaluation must also be made by a local authority before making a decision. As the proposed plan change “imposes a greater prohibition or restriction to an activity to which a national environmental standard applies than any prohibition or restriction in the standard” (RMA 32[[3A)), the evaluation must also take into account

32.4(a) the benefits and costs of policies, rules or other methods; and 32.4(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.

The objective of this proposed plan change represents Clause 5 of Part 2 of the Resource Management Act which states: 5 Purpose (1) The purpose of this Act is to promote sustainable management of natural and physical resources. (2) In this Act, sustainable management means managing the use, development, and protection of natural and physical resources in a way, or at a rate, which enables people and communities to provide for their social, economic, and cultural wellbeing and for their health and safety while—

(a) Sustaining the potential of natural and physical resources (excluding minerals) to meet the reasonably foreseeable needs of future generations; and (b) Safeguarding the life-supporting capacity of air, water, soil, and ecosystems; and (c) Avoiding, remedying, or mitigating any adverse effects of activities on the environment.

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All Proposed changes in this report are in accordance with this purpose of the Resource Management Act.

4.1.2. Relevant Functions of Council (section 30 and 31) Sections 30 and 31 of the Resource Management Act outline Council’s responsibility as a local and territorial authority, respectively: Section 30: (1) Every regional council shall have the following functions for the purpose of giving effect to this Act in its region:

(c) The control of the use of land for the purpose of -- (iiv) The avoidance or mitigation of natural hazards (d) In respect of any coastal marine area in the region, the control (in conjunction with the Minister of Conservation) of – (v) Any actual or potential effects of the use, development or protection of land, including the avoidance or mitigation of natural hazards (…)

Section 31: (1) Every territorial authority shall have the following functions for the purpose of giving effect to this Act in its district:

(a) The establishment, implementation, and review of objectives, policies and methods to achieve integrated management of the effects of the use, development or protection of land and associated natural and physical resources of this district [(b) the control of any actual or potential effects of the use, development, or protection of land, including for the purpose of – (i) the avoidance or mitigation of natural hazards

[(2) The methods used to carry out any functions under subsection (1) may include the control of subdivision.] These abstracts clearly show Council’s responsibility to manage land use in a way that minimises the effects of natural hazards including coastal flooding. This objective can be reached by implementing land use rules for a Coastal Flood Hazard Overlay.

4.1.3. New Zealand Coastal Policy Statement 2010 All policies of the New Zealand Coastal Policy Statement have to be taken into account for this proposed plan change and variation. The relevant policies are: 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 for 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; 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: 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 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;

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• (c) encourage redevelopment, or change in land use, where that would increase 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;

(d) recognising and considering the environmental and social costs of permitting hard protection structures to protect private property; and

(e) identifying and planning for transition mechanisms and timeframes for moving to more sustainable approaches.

(2) In evaluating options under (1): (a) focus on approaches to risk management that reduce the need for hard protection structures

and similar engineering interventions; (b) 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 (c) 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.

4.1.4. Regional Policy Statement

As explained in Chapter 4.1.1 do plan changes have to be consistent with the Regional Policy Statement. Relevant abstracts from Gisborne’s regional Policy Statement are: 2.3.1 Objectives

1. A pattern of human settlement that: • provides a high level of personal safety from natural hazards for its inhabitants; • avoids or mitigates the risk to property and infrastructure from natural hazards; • does not accelerate or worsen the effects of natural hazards upon the natural and

physical environment. 2.3.2 Policies

1. To encourage and facilitate changes, over time, to patterns of human settlement, development and activities which are not affected by natural hazards and which do not

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induce or worsen the impacts of natural processes, and which recognise and allow for some natural features to migrate inland as a result of dynamic coastal processes.

3. To maintain a strong commitment to researching, recording and publicising information about natural hazards.

3. To recognise that natural systems and features may provide a defence against natural hazards and that the integrity of such natural systems should be protected and enhanced where appropriate.

4. To recognise the possibility of sea level rise and the likelihood of changes to the frequency and impacts of some natural hazards due to climate change and sea-level rise.

2.3.3 Methods

1. Maintain accurate and accessible records and information about natural hazards, both generally and in respect of particular sites or localities.

3. Identify sites and topics where further knowledge is required and undertake appropriate research.

5. Adopt methods, including rules, in district and regional plans controlling development in areas affected or potentially affected by natural hazards that prevent, restrict or require special design or precautions, as appropriate.

4.1.5. Part Operative Combined Regional Land and District Plan for the Gisborne

District The changes are proposed for the Part Operative Combined Regional Land and District Plan and can be found in Chapter 6.1. Relevant abstracts from the current version of this document are: 5.3 General Objectives

1. A pattern of human settlement that: • provides a high level of personal safety from natural hazards for its inhabitants; • avoids or mitigates the risk to property and infrastructure from natural hazards; and • does not accelerate or worsen the adverse effects of natural hazards upon the natural

and physical environment. 2. A community informed of the potential natural hazards of the District. 3. The protection of natural features that could lessen the impact of natural hazards.

5.4 General Policies

1. In extreme hazard areas where the natural hazard cannot be avoided or mitigated new development and any related subdivision should not occur.

2. In all hazard prone areas, any new subdivision, use and development should avoid or miminise any risk of loss of life or injury or other environmental damage due to natural hazard.

3. Patterns of human settlement, development and activities should not induce or accelerate the risk of natural hazards. When assessing an application for a resource consent the effects of that application on any hazard risk shall be considered. This includes but is not limited to the following: • likelihood of increased erosion elsewhere; • extent to which natural buffers exist and are adversely affected.

8. In carrying out hazard assessments or considering resource consent applications the possibility and implications of climate change are to be recognised. In particular the likelihood of the following matters should be considered: • a change in sea level; • altering of coastal processes; • increased inundation of low lying estuarine areas; • higher local temperatures; • changes in rainfall patterns; • increase in cyclonic storms.

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5.16 METHODS OF IMPLEMENTATION There is a diverse range of natural hazards experienced in this District. Strategies are developed for each individual hazard, generally involving a combination of the following methods: 5.16.1 Information and Research

1. Council will continue to carry out research to improve its knowledge of particular hazards in particular areas.

5. Council will undertake new, and review existing, flood and inundation hazard assessments, as follows: • Carry out further Coastal Hazard Zone Assessments for parts of the coastline subject to

development pressure. Initial priorities include Tolaga Bay, Anaura Bay, Tokomaru Bay, Te Araroa and Hicks Bay.

5.16.3 Regulation

3. The Council will include areas subject to natural hazards in Hazard Overlays on the Urban and Rural planning maps. Restrictions applying to these Overlays will be included in this Plan.

4. Overlays include the following: o) Coastal Hazard Overlay 1 - Extreme Risk Area: This area lies adjacent to the coast and

encompasses the area subject to high impact short-term shoreline fluctuations. There is a significant possibility of values being damaged or destroyed in any one year. Erosion could occur to the full width of this area in a single storm.

p) Coastal Hazard Overlay 2 - High Risk Area: This area lies adjacent to and landward of the Extreme Risk Area. It encompasses the area subject to potential sea and wind erosion, flooding or landslip with a high probability of occurring between now and the year 2050 AD. The shoreline is forecast to lie at the inland edge of this area by about the year 2050 AD.

q) Coastal Hazard Overlay 3 - Moderate Risk Area: This area lies adjacent and landward of the High Risk Area. It encompasses the area subject to potential sea and wind erosion, flooding and landslip with a high probability of occurring during the period 2050 2100 AD. The shoreline is forecast to lie at the inland edge of this area by about the year 2100 AD according to the 1995 Coastal Hazard Assessment.

r) Coastal Hazard Overlay 4 - Safety Buffer: This area is likely to be affected by coastal erosion beyond the year 2100 AD on present assumptions. This would be affected by any change in the rate of sea-level rise and any change in storm frequency due to climate change. Buildings erected now are likely to be still in existence by the time the area comes to be affected by erosion. It has been mapped now for advance warning and to enable the rate of change

to be monitored. s) Areas Subject To Coastal Hazard (ASCH): See the Regional Coastal Environment Plan.

These are areas which have been assessed as being potentially subject to coastal hazard. A preliminary study of these areas was carried out in 1994 by Dr J.G. Gibb for the Council. This was based on the factors of sea and wind erosion, landslip and flooding from the sea and coastal rivers. These areas are identified in the aerial photographs in the Map Volume of the Gisborne District Combined Regional Land and District Plan. The majority of the Gisborne coastline is affected. (See also the Regional Coastal Environment Plan). The results of the study will be incorporated by the Council into Land Information and Project Information Memoranda, and in decisions on building consents, resource consents and subdivisions. Developers of sites in these areas may be required to carry out more in depth analysis of the degree of hazard as part of their applications. The areas concerned are shown on aerial photographs included with the Urban and Rural planning maps.

5.16.5 Public Awareness 1. Council will build public awareness of natural hazards and their effects.

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4.1.6. Proposed Regional Coastal Environment Plan Changes also include an adaption of the Proposed Regional Coastal Environment Plan. Abstracts from the current version of this document are: 3.8.3 Objectives

3.8.3A Identify the areas where natural hazards may occur for all the Gisborne District coastline within 5 years.

3.8.3B New subdivision, use, and development and human settlement patterns in the Coastal Environment which: o Maximise personal safety from natural hazards. o Ensures that property and community infrastructure is less at risk of loss or

damage from natural hazards. o Does not accelerate or worsen or cause transfer of adverse effects of natural

hazards on the environment. o Preserves the natural character of the Coastal Environment and protects the

amenity values and quality of the Coastal Environment from any adverse effect arising from activities undertaken in response to natural hazards.

3.8.3D Agencies and members of the general public are aware of areas of the coast identified as being areas subject to natural hazards and appreciate the dangers associated with subdivision, use, and development in those areas.

3.8.3E Natural features, such as dune systems and estuaries, and physical processes are maintained or enhanced in order to maintain natural buffers against natural hazards which occur in the Coastal Environment.

3.8.4 Policies

3.8.4A The Council will adopt a two-tiered assessment of areas prone to natural hazards associated with coastal erosion, storm surge inundation and slips. These assessments will be incorporated into the Regional Coastal Environment Plan and the District Plan for the Gisborne District.

3.8.4D Council shall adopt a minimum planning horizon of 100 years for ASCH and CHZ assessments.

3.8.4H Council shall take into account projected changes in sea level as a result of global warming when preparing ASCH and CHZ assessments and shall adopt the Intergovernmental Panel on Climate Change (IPCC) “best estimate” rise in sea-level projection.

3.8.4M When assessing subdivision consent applications in the Coastal Environment, Council shall have regard to any coastal flood hazards.

3.8.4Q Council and consent authorities shall discourage new development in areas that are known to be at high risk from coastal hazards within the Coastal Environment unless either: a) the development is necessary for the operation of regionally important infrastructure

such as Port Gisborne, and b) there is no practical alternative; or c) the proposed development will not be significantly affected by coastal hazards or

affect natural features that act as buffers against natural hazards. And in the case of (b) and (c) above:

i) the development is unlikely to lead to a demand for protection works. ii) in the event of a hazard occurring, any resulting damage will not result in

significant adverse effects on the environment including the safety of the general public.

3.8.4R The Council will maintain a strong commitment to researching, recording and publicising information about natural hazards in the Coastal Environment.

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3.8.5 Methods 3.8.5A Council will undertake a rapid hazards assessment of the entire coast. This will be known

as an Area Sensitive to Coastal Hazards (ASCH) assessment. A more detailed assessment known as a Coastal Hazard Zone (CHZ) assessment will be undertaken for areas where there is a high degree of risk revealed by the ASCH assessment and significant development has occurred, or is likely to occur, and be at risk from natural hazards.

3.8.5D Where new ASCH assessments or CHZ assessments have been completed, Council shall incorporate those assessments into the Regional Coastal Environment Plan and District Plan, within three months of their completion, by way of commencing a Plan Change pursuant to the first schedule of the Resource Management Act 1991.

3.8.5F ASCH assessments and CHZ assessments will be undertaken using the standard methodologies and criteria set out in the report to Council, “Section 32 analysis of criteria to be included in the Regional Coastal Environment Plan for assessing coastal hazard areas in the Gisborne District; Appendix 1” and reproduced here in Appendix 5.

3.8.5H Council will publish new information on natural hazards and promote greater understanding of the natural processes that give rise to such hazards.

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4.2. Objectives The main objective for the plan change is to reach an objective from the District Plan and the Regional Policy Statement:

“1. A pattern of human settlement that: • provides a high level of personal safety from natural hazards for its inhabitants; • avoids or mitigates the risk to property and infrastructure from natural hazards; and • does not accelerate or worsen the adverse effects of natural hazards upon the natural and physical environment. 2. A community informed of the potential natural hazards of the District. 3. The protection of natural features that could lessen the impact of natural hazards.”

A further objective is to develop rules that lead to consistent decision-making concerning land use in zones at a higher risk from coastal flooding. The rules will help make future land use less prone to damage from coastal flooding and give both Council staff and land owners in the Coastal Flood Hazard Zones more certainty about the risks and restrictions for building in the zones.

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4.3. Analysis of Proposed Changes and Alternative Measures

4.3.1. Introduction The proposed changes include a variation to the Coastal Plan and a change to the District Plan, including incorporating the Coastal Flood Hazard Overlays into the urban and rural planning maps and plans. The proposed changes can be found in Chapter 5.2. The rules were developed in cooperation with the Rivers and Land Drainage team, also taking into account the community’s ideas and concerns. The proposed rules as well as alternative measures to mitigate the damage flooding might have in the future will be taken into account. Section 32 of the Resource Management Act requires Council to assess benefits, costs, effectiveness and efficiency of the proposed plan changes in a comparison with other measures. This assessment has been conducted in an analysis of benefits and costs. The analysis (Chapter 4.3.3) compares the benefits, costs, statutory requirements, efficiency and effectiveness of five management options to reach the objectives stated in Chapter 4.2. The strategies compared are

• Status quo- no changes • Incorporating the Coastal Flood Hazard Zones and rules for these zones in the district’s

Regional and District Plans. • Protection works for the minimisation of adverse effects of coastal flooding in Coastal

Flood Hazard Zones • Communication and Education • Relocation Rates Relief

Furthermore has community consultation given an insight into the community’s concerns and ideas (Chapter 4.3.2). Chapter 5.1 concludes the results of the analysis of benefits and costs and the community meetings and gives a recommendation on whether or not to implement the plan change or other measures to reach the objectives as defined in Chapter 4.2.

4.3.2. Outcomes of the Community Consultation Meetings In public meetings with the three affected communities, Council was able to get to know the communities’ concerns and ideas for managing the Coastal Flood Hazard Zones. The meetings showed how different the communities think about the issue. For Anaura Bay, coastal flooding does not seem to be a major concern. The community is more focused on other issues such as slips from the hills, the effectiveness of the tsunami-warning system and the erosion of an old graveyard. Ideas for future building in the community include movable buildings, using lower levels of buildings for non-residential purposes such as a garage and specified floor heights which let the water flow underneath the house. It was mentioned that this would be difficult in lower areas were floor heights of several meters would be needed. One community member noted that they were required to build their house with a certain floor height. The community member accepted the condition as it improved the safety of the building and did not add any extra costs, making it “worth the trouble”. A member of the community mentioned that she sees Anaura Bay as a unique community which is aware of the flood risk, with most people having lived there for many years. In her opinion, there is little development and not much changing-hands of land which leads to a very small risk of major subdivisions. In Tolaga Bay, there is some concern about rules posing a threat to the growth of the town, especially the camp ground. The community members point out that the southern part of the CFHZ is an area which is important for the community’s economy and has the potential to grow in the future. Many of the reasons for Tolaga Bay’s existence are situated here, such as the Wharf and the camp ground.

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For this area, the community is keen to see long-term growth in the future. The northern part of the CFHZ is perceived to be less significant for Tolaga Bay and less development is expected to occur here. The community points out that the area has a lot of potential and that there is no reason for the area not to grow. Another issue mentioned by the community is that they do not want complicated regulations and restrictions which make it difficult and time-consuming to apply for a consent. For the community, it is important that the rules do not involve “too much red tape” and engineering reports. There are already many different zones for one area of land which can make things complicated for the communities. The community explains that they do not want to have too much restriction and regulation as this could “kill” the camp ground. The community wants Council to be careful about putting regulations in that slow down the process of getting a building/resource consent. The processes are often too complicated, requiring several different reports. In Muriwai, no one came to the meeting. As the meeting was widely-promoted, this is most probably a sign for the community of Muriwai not seeing the Coastal Flood Hazard Zones as a priority. Ideas for managing the Coastal Flood Hazard Zones that were mentioned in the meetings included minimum floor heights, movable buildings and dune care groups to minimize erosion of the dunes. The complete minutes can be found in Appendix 5.

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4.3.3. Analysis of Benefits and Costs

Option Benefits Costs Statutory Responsibility Efficiency EffectivenessStatus Quo Do not incorporate the Coastal Flood Hazard Zones and rules for land use, subdivision anddevelopment ofCoastal Flood Hazard Zones in the Regional Coastal Environment Plan and the Combined Regional Land & District Plan.

CFHZ still useful as background information fordecision-makers and (future) land owners.

Continue to decide on consents in a case-by-case manner. Do not take any new actions against the adverse effects of coastal flooding.

Flexibility in decision-making for building consents in CFHZ.

Possibly larger costs for future coastal protection works and staff due toinconsistent, time-consuming decision-making.

No increase in insurance costs for land owners if Coastal Flood Hazard Zones are not incorporated in Regional and District Plans.

No direct costs for implementation.

Policy 24 “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 for being affected.” (Coastal Flood Hazard Zones have been identified but are not incorporated in policy statements and plans)

Adverse effects on quality of decisions and community’s trust in and credibility of Council due to inconsistent decision-making. Cost for developers to undertake coastal floodhazard assessment as part ofAssessment of Environmental Effects

Policy 2.3.2 (1) “To encourage and facilitate changes, over time, to patterns of human settlement, development and activities which are not affected by natural hazards and which do not induce or worsen the impacts of natural hazards.”

Method 2.3.3 (6) “Adopt methods, including rules, in district and regional plans controlling development in areas affected or potentially affected by natural hazards that prevent, restrict or require special design or precautions, as appropriate.” (Currently decisions are usually made in consistence with this objective, however, there are no rules in the plans)

Not consistent with Coastal Plan: Policy 3.8.4A “The Council will adopt a two-tiered assessment of areas prone to natural hazards associated with coastal erosion, storm surge inundation and slips. These assessments will be incorporated into the Regional Coastal Environment Plan and the District Plan for the Gisborne District.” Partially consistent with New Zealand Coastal Policy Statement 2010:

Partially consistent with the New Zealand Coastal Policy Statement 2010: Policy 25(b) “In areas potentially affected by coastal hazards over at least the next 100 years: avoid redevelopment, or change in land use, that would increase the risk of adverse effects from coastal hazards” (Adverse effects are avoided on a case-by-case basis through resource consents but no legal support for decisions incorporated in district plans) Partially consistent with Regional Policy Statement:

Due to the assessment ofbuilding consents on an individual basis, theassociated costs and time for consents aresignificantly higher compared to having set rules.

While development and subdivision of areas in zones prone to coastal flooding would most certainly be prohibited on an individual basis without the development of new rules, the decision-making is less consistent and there might be a greater risk of wrong decisions leading to adverse effects of coastal flooding.

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Option Benefits Costs Statutory Responsibility Efficiency EffectivenessAdoption of Coastal Flood Hazard Zones Incorporate Coastal Flood Hazard Zones into the Coastal and District Plans. Include rules (e.g. minimum floorheights) concerning land use, subdivision and development in Coastal Flood Hazard Zones in the Regional Coastal Environment Plan.

Objective future decision-making for building consents in the Coastal Flood Hazard Zones which is consistent in time and within all four areas.

Certain degree of avoidance of future protection works. Regional rules would allow Council to prohibit certain types of development that would be situated in a zone in risk of coastal flooding.

More defined rules can lead to a decreased requirement of staff in the long term as not every building consent has to be researched and assessed separately. More detailed information in the Coastal and District Plans about which areas are at risk from coastal hazards. Information for (future) land owners on the hazards associated with the area. Resource consent applicants are not required to undertake coastal flooding hazard assessment.

Due to uncertainties about climate change and some general unpredictability ofcoastal hazards, the zones could bequestioned in costly legal contests.

Policy 3.8.4A “The Council will adopt a two-tiered assessment of areas prone to natural hazards associated with coastal erosion, storm surge inundation and slips. These assessments will be incorporated into the Regional Coastal Environment Plan and the District Plan for the Gisborne District.”

The regional rules would not have any effect on existing buildings which would still be situated in a zone prone to coastal flooding. Direct costs associated with the changes of plans. Possibly increasedinsurance costs for land owners in the Coastal Flood Hazard Zones.

Policy 25(b) “In areas potentially affected by coastal hazards over at least the next 100 years: avoid redevelopment, or change in land use, that would increase the risk of adverse effects from coastal hazards”

Opportunity costs due to people not building in the CFHZ (lost rates).

Consistent with Coastal Plan:

Consistent with the New Zealand Coastal Policy Statement 2010: “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 for being affected”. Consistent with the New Zealand Coastal Policy Statement 2010:

Consistent with Regional Policy Statement: Policy 2.3.2 (1) “To encourage and facilitate changes, over time, to patterns of human settlement, development and activities which are not affected by natural hazards and which do not induce or worsen the impacts of natural hazards.” Method 2.3.3 (6) “Adopt methods, including rules, in district and regional plans controlling development in areas affected or potentially affected by natural hazards that prevent, restrict or require special design or precautions, as appropriate.”

Regional ruleswould reduce the costs associated with theassessment ofbuilding consents as the assessment does not have to be conducted separately for each application.

Implementing regional rules would lower the risk of new developments in the CFHZ being adversely affected by coastal flooding. The risk of flooding in the CFHZ would not be decreased for existing developments. The Coastal Flood Hazard Zones were developed by an experienced practitioner and give an orientation for locations in risk of coastal flooding. As coastal hazards are difficult to predict and influenced by climate change, the coastal flood hazard zone borders can not be seen as a guarantee for future events as there always is a degree of uncertainty and unpredictability.

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Option Benefits Costs Statutory Responsibility Efficiency EffectivenessProtection Works for the minimization of adverse effects of coastal flooding in CFHZ Hard measures Using hardengineering techniques such as sea walls, groynes or multipurpose reefs.

Certain degree of safety from coastal flooding for new and existing development in Coastal Flood Hazard Zones in the short and medium term.

Protection of Councilinfrastructure from flooding.

Potential adverse effects of hard structures on natural barrier in the long term.

Positive effects of multipurpose reefs on amenity values (diving, surfing) and ecological values.

Adverse effects on ecology, public access and amenity values (except multipurpose reefs).

High associated costs with the building of the structure(s) would lead to significantly higher (targeted) rates. Costs associated with maintenance ofstructures would further increase rates.

Soft measures Dune Care/CoastCare (possibly community groups) to strengthen the natural barrier against coastal inundation.

Certain degree of safety from coastal flooding in the short term.

Sand nourishments to heighten andstrengthen the natural barrier against coastal inundation.

Protection of Councilinfrastructure from flooding.

Possibly increased amenity values where sandnourishments lead to a widening of the beach.

Direct costs associated with the establishment of dune/coast care groups and sand nourishments would increase rates.

Dune/Coast care groups might increase ownership and feeling for responsibility of community for the coast.

During sandnourishments restricted beach access.

a) The probability of the works providing effective long-term protection.” (Uncertainty about long-term effectiveness of coastal protection works)

Costs for replenishing the sand after a few years due to ongoing erosion would further increase rates.

Inconsistent with Regional Policy Statement: Policy 2.3.2 (2) “To recognise the limitations of attempts to control natural processes by physical work and limit such attempts to appropriate situation where they:

• Have a favourable benefit to cost ratio; and

• Can be designed with confidence for long-term effective performance.”

(Uncertainty about long-term effectiveness of coastal protection works) Inconsistent with the Coastal Plan: Policy 3.8.4P “Coastal hazard protection works may be considered in relation to existing use or development of areas of the Coastal Environment. Determination of applications for resource consent will include consideration of:

Partially consistent with the District Plan: “Council will provide and maintain erosion protection measures where these are necessary and the most effective means of mitigating natural hazards.” (Consistent for existing infrastructure where no effective alternatives can be found)

Life span of hard engineering techniques longer than that of soft techniques but both requireregular maintenance/ replenishment.

Risk of coastal inundation can be decreased but not excluded even with coastal protection structures in place.

Possibly new developments in areas prone to coastal flooding due to lower perceived risk. As the Coastal Flood Hazard Zones are only sparsely populated but cover a large area, the coastal protection works are most certainly not economically efficient.

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Option Benefits Costs Statutory Responsibility Efficiency EffectivenessCommunication andeducation

The community is informed about the risks associated with the Coastal Flood Hazard Zones.

Developing a communication andeducation concept to inform and educate the community about the existing risks.

Decisions on land use and development might be influenced in such a way that less people decide to build in an area in risk of coastal inundation.

The community might want to be involved in the protection of the coast and start up coast/dune care groups. Possibly decreased costs associated with assessment of building consents due to less people wanting to build in flood hazard zones.

Direct costs associated with developing and producing the means of education/ communication, public meetings etc.

If combined with regional rules generally consistent with all relevant policy statements and plans.

Compared to other strategies (e.g. coastal protection works)significantly smaller costs.

Knowledge of hazards does not necessarily influence the community’s behaviour, even when knowing the hazard zones and associated risks people might want to build in a Coastal Flood Hazard Zone.

For long-term efficiency, measures should be repeated after a few years.

Option Benefits Costs Statutory Responsibility Efficiency EffectivenessRelocation Rates Relief Offering rates reliefs to land owners who move their dwelling out of the Coastal Flood Hazard Zones.

If land owners move their dwellings out of the Coastal Flood Hazard Zones, less dwellings are in risk of coastal flooding. Less costs for coastal protection works which are not needed if no dwellings are situated within hazard zone.

Indirect costs associated with lost rates. Direct costs for Plan Changes. Even with rates relief a reaction from land owners is not guaranteed.

Consistent with Regional Policy Statement: “To encourage and facilitate changes, over time, to patterns of humansettlement, development and activities which are not affected by natural hazards and which do not induce or worsen the impacts of natural hazard.”

If the opportunity is taken by the community this can be efficient as the costs associated with the relocation rates relief can be outweighed by a significantly higher level of safety for the community.

No guarantee on whether or not land owners move their dwellings out of the Coastal Flood Hazard Zones.

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5. Conclusion The analysis of benefits and costs has shown that the development of rules for land use, development and subdivision of the Coastal Flood Hazard Zones is an effective measure to improve the decision-making concerning land use in the Coastal Flood Hazard Zones. Currently, the method of dealing with the calculated zones does not comply with several policies and plans which require the implementation of hazard zones and rules for these zones. The development of rules and the implementation of the Coastal Flood Hazard maps in the Proposed Regional Coastal Environment Plan and the Part-operative Combined Regional Land and District Plan are consistent with all relevant policies and plans. The technique is also expected to be effective and efficient, with the benefits outweighing the costs in the long-term. The development of land use rules and their implementation in the plans is therefore recommended. Coastal protection works are presumably not consistent with several policies and plans as their long-term effectiveness is often questionable. Also are the associated costs for implementing and maintaining coastal protection works very high. Due to the Coastal Flood Hazard Zones being relatively sparsely-populated and large, the widespread use of coastal protection works is not feasible. Communication and education are cost-efficient measures for supporting the regional rules. With relatively small financial input, the community’s awareness of the hazards can be improved, influencing land use behaviour. A relocation rates relief implies a certain risk as it does not guarantee the relocation of the dwellings. Also are there relatively many dwellings positioned in the Coastal Flood Hazard Zones. A relocation of all of these dwellings would mean large amounts of lost rates. The development of rules in a combination with a communication and education strategy is the most effective measure and associated with benefits outweighing the costs by far. The pre-consultation meetings mainly focused on rules for land use, subdivision and development in the Coastal Flood Hazard Zones. There were some main conclusions that Council gained from the meetings:

• The communities explained that they did not want the process of being allowed to build to get any more complicated.

• One community member was required to build with a certain floor height which did not add any extra costs

• Many community members, especially in Anaura Bay, are more concerned about other hazards (land slides)

• Concerns about possibility of future growth (especially Tolaga Bay camp ground)

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6. Recommendations

6.1. The Proposed Plan Changes

District Plan Changes: 5.13 COASTAL HAZARDS 5.14 Introduction …This assessment process determined the extent of coastal hazards, forecast shoreline positions for the years 2050 and 2100 AD and provided the basis to determine the relative degree of risk by risk zoning. The coastal flood hazard zone was calculated for Tolaga Bay, Anaura Bay and Muriwai. The landslip and erosion CHZ was divided into extreme, high and moderate risk zones and a safety buffer zone. Further detailed Coastal Hazard Zone assessments were subsequently carried out as follows: 1998: Tolaga Bay and Anaura Bay 2001: Wainui Beach (review of 1995 CHZ) 2004: Southern Poverty Bay 2008: Tokomaru Bay 5.16 METHODS OF IMPLEMENTATION 5.16.3 Regulation 4. Overlays include the following: s) Areas Subject To Coastal Hazard (ASCH): See the Regional Coastal Environment Plan. These are areas which have been assessed as being potentially subject to coastal hazard. A preliminary study of these areas was carried out in 1994 by Dr J.G. Gibb for the Council. This was based on the factors of sea and wind erosion, landslip and flooding from the sea and coastal rivers. These areas are identified in the aerial photographs in the Map Volume of the Gisborne District Combined Regional Land and District Plan. The majority of the Gisborne coastline is affected. (See also the Regional Coastal Environment Plan). t) Coastal Flood Hazard Zones These are areas of coastal hinterland which are subject to or are likely to be subject to episodic, temporary inundation by the sea, excluding tsunami. The zones were calculated by Dr Gibb for Anaura Bay, Tolaga Bay and Muriwai in his assessments of Coastal Hazard Zones in 1998 and 2004. The calculations are based on historic storm wave run up levels and the zones are represented by contour lines above Mean Sea Level. 5.35 Regional Rules for Coastal Flood Hazard Overlay 5.35.1 Permitted Activities

The following activities shall be permitted activities: 5.35.1.1 Internal alteration of residential buildings; habitable buildings, decks and pergolas attached to an existing residential building 5.35.1.2 Accessory buildings associated with a residential dwelling in the area 5.35.1.3 Construction, additions to or alterations to the upper floor levels of any existing residential or habitable buildings. 5.35.1.4 Construction of new residential/habitable buildings or conversion of accessory buildings or non-habitable rooms into residential/habitable buildings or rooms Provided that: 5.35.1.4.1 All residential buildings shall have minimum habitable floor levels as specified in Table 1 below, based on the expected storm wave run-up of a 100-year flood including a 600 mm safety margin.

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• Table 1: Minimum habitable floor levels

Location Minimum habitable floor levelMuriwai 3.60 m a.MSLTolaga Bay 3.60 m a.MSLAnaura Bay North of and around Waipere Stream 4.60 m a.MSLAnaura Bay South of Waipere Stream 4.10 m a.MSL

5.35.2 Restricted discretionary Activities

The following activities shall be restricted discretionary activities: 5.35.2.1 Any new road, road alteration or shape correction that alters the pavement level 5.35.2.2 Any activity including earthworks that alters natural landforms 3.35.2.3 Relocation of or additions to residential /habitable buildings Council shall restrict its discretion with regard to 5.35.2.1-5.35.2.3 to the matters a) – b) specified below: a) Restriction or diversion of the passage of floodwaters b) The potential impact on lives or property in the event of flooding

5.35.3 Prohibited Activities

The following activities shall be prohibited activities: 5.35.3.1 Construction of new residential buildings and habitable buildings which do not meet the minimum habitable floor heights as defined in table 1.

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Coastal Plan Variation

Chapter 3.8 Natural Hazards Activities 3.8.4.CD The amalgamated assessments of Coastal Flood Hazard Zones for Muriwai, Tolaga Bay and Anaura Bay and data contained in the report and A3 cadastral maps prepared for the Gisborne District Council in 1998 (Anaura Bay and Tolaga Bay) and 2004 (Muriwai) are adopted as CFHZs for inclusion in this Plan and the District Plan of the Gisborne District and the data from the cadastral maps is reproduced in Appendix 6 of this Plan. Explanation: Reports prepared for the Gisborne District Council on coastal flood hazard zones assessed for southern Tolaga Bay, Muriwai and Anaura Bay must be incorporated into the Regional Coastal Environment Plan in order for them to attain legal status. These reports set out in detailed map form and data form within a planning horizon of 100 years. This information is reproduced in Appendix 6 of this Plan and has been incorporated onto the GIS computer system of the Gisborne District Council. Principal reason: This policy implements Objective 3.8.3A and 3.8.3B and 3.8.3D of this Plan and Policy 3.4.1and 3.4.5 of the New Zealand Coastal Policy Statement. 3.8.5J Council will investigate the feasibility of preparing Coastal inundation Hazard Areas for inclusion into the RCEP and the District Plan. Areas which may be assessed as a matter of priority are Poverty Bay, Wainui Beach and Tolaga Bay. Principle Reason: Policy 3.4.1 of the NZCPS requires Council to identify areas in the Coastal Environment where natural hazards exist. This method is required to implement Policy 3.8.4M. 3.8.5J Council will conduct further research into the Coastal Flood Hazard Zone in Tokomaru Bay excluding tsunami and include this zone in the district’s plans. Principle Reason: The Coastal Flood Hazard Zone in Tokomaru Bay is based on higher tsunami run-up levels than storm wave run-up levels. The data is not suitable to base land use planning on tsunami hazards. The zone therefore has to be re-calculated to exclude the tsunami risk and represent purely flooding from storm events.

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6.2. General Recommendations After conducting extensive pre-consultation with the communities and discussing possible rules with the Rivers& Land Drainage Team and the Natural Resources Policy Team, a set of rules for land use in the Coastal Flood Hazard Zones is recommended. The proposed plan changes can be found in Chapter 6.1. Furthermore is it recommended to undertake further research to determine the Tokomaru Bay CFHZ excluding tsunami so that this zone can be added to the district’s plans. The specified minimum floor heights should be updated should new reports from the International Panel on Climate Change on sea level rise require this. A rule allowing movable buildings in the CFHZ is not recommended as the process of moving the buildings takes too long to be feasible before a flooding event. It is recommended to incorporate the proposed rules in the Part Operative Combined Regional Land and District Plan and in the Proposed Regional Coastal Environment Plan. Furthermore can communication and education be supportive in managing land use. By informing communities about the hazards, their behaviour might be changed and awareness of the risks can be increased. Coast care groups can also be supportive in enforcing the natural barriers, especially sand dunes.

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Reference List

• Bell, G.R. & Gorman, R.W. (2003) Coastal Hazards. The Natural Hazards Centre, NIWA. • Gibb, J. 1995. Assessment of Coastal Hazard Zones for Northern Poverty Bay and Wainui Beach,

Gisborne District. Report prepared for the Gisborne District Council. • Gibb, J. 1998. Assessment of Coastal Hazard Zones for Tolaga Bay and Anaura Bay, Gisborne District,

by GIS Computer Model. Report prepared for the Gisborne District Council. • Gibb, J. 2004. Assessment of Coastal Hazard Risk Zones for the Southern Poverty Bay Area. Report

prepared for the Gisborne District Council. • Gisborne District Council. 2006. Combined Regional Land & District Plan. Gisborne District Council. • Ministry for the Environment. 2008. Coastal Hazards and Climate Change. A Guidance Manual for

Local Government in New Zealand. 2nd edition. Revised by Ramsay, D., and Bell, R. (NIWA). Prepared for the Ministry for the Environment.

• Wang, X.; Prasetya, G.; Power, W.; Lukovic, B.; Brackley, H.; Berryman, K. 2009. Gisborne District Council Tsunami Inundation Study, GNS Science Consultancy Report 2009/233

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Appendices 1 Variation/Plan Change Process 2 Maps of the CFHZ 3 Minutes of the public meetings

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Appendix 1: Variation/Plan Changes Process

Appendix 2: Maps of the Coastal Flood Hazard Zones

• Anaura Bay • Muriwai • Tolaga Bay

The Coastal Flood Hazard Zones are indicated by the yellow areas. Please note that the scales are slightly off due to printing settings.

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APPENDIX 3: Minutes from the Public Meetings

DISCUSSION NOTES

P O Box 747, Gisborne, Ph 867 2049 Fax 867 8076 Email [email protected]

Web www.gdc.govt.nz

Notes from Public Discussions on Coastal Flood Hazard Zones (Anaura Bay, Muriwai and Tolaga Bay) Over the past month staff have met with the following communities to discuss local coastal flood hazards:

• Anaura Bay (13 October, 5.15 – 6.30pm at GDC Committee Room)

Ben Tahata, Cheryl Clarke, Kay Goldsbury, Kelvin Bayley, Mark and Pam Pickett, Mike and Liz Swanson, Patrick Burke, Ruth Paerata, Te Rawhiti Paerata and Councillor Pat Seymour.

• Muriwai (9 November at Muriwai School)

No attendees.

• Tolaga Bay (20 October, 6.00 – 7.00pm at Tolaga Bay Fire Station)

Dion Milner, James Milner, Peter Andrew and Councillor Pat Seymour.

Below is a record of the key points from all of those meetings so that community members are aware of the discussions that have been held across the District and have a full picture.

1. Presentation from Council staff What is coastal flooding? Coastal flooding can occur due to a combination of several factors: high tide; wind and storms pushing waves onshore; low air pressure; and wave run up.

Wave run-up

High tide

Wind / storm

Low air pressure (sucks the water up)

What are the effects of coastal flooding? Coastal flooding can cause water damage to properties and buildings, salt water contamination of pasture land and soil erosion from water flow.

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http://www.gdc.govt.nz/

What are the coastal flood hazard risks in the Gisborne District? Council has a well-established programme of identifying and managing coastal hazards. prepared reports on three areas.

Flood hazards Zones in 3 areas – Muriwai, Anaura Bay and Tolaga Bay.

Calculated by Dr Jeremy Gibb

Based on historic water levels during storm events

What options are there for managing risks? There are several options for reducing coastal flood hazard risk: regulations for managing land use in the District Plan; providing information on where the risks are and how to manage them at a property level; establishing protection works; and financial strategies.

What are we doing? Apart from Anaura Bay, Coastal Flood Hazard Zones are also located in Tolaga Bay and Muriwai so the meeting is part of a bigger process including several locations. An assessment by Dr Jeremy Gibb found several risks for different hazards along Gisborne’s coastline.

Council’s preferred option at the moment is the development of land use provisions for these zones and education. The effects of coastal flooding are very different to the effects of erosion and landslips as flooding only inundates land for a certain time but does not take land away as erosion would. Therefore, Council would like to take a different approach for managing these coastal flooding zones in which certain activities are still possible. Currently, Council is working out these possibilities.

2. Discussion of the new proposed Anaura Bay Coastal Flood Hazard Zone Some community members mention that slipping and flooding of the access road to Anaura is a major issue for them. Reasons for the flooding could be the blocking up under the bridge or the Hikuwai River coming in sideways and the water not being able to flow off due to the high pressure of the water in the river. Yvette Kinsella and Katrin Markull will mention this problem to the Rivers & Land Drainage Team.

A community member mentions that the area near the road was flooded in 1919 and 1939 which led to the settlements being moved to the beach instead where the perceived risk of flooding was smaller.

Another issues mentioned is the spring tanks along the hill near the slip.

Anaura Bay is shallow, which might protect it from large waves during tsunami or big storms. Dr Gibb also mentions this in the hazard assessment report and takes it into account in the calculation of the contour lines of flooding risk. This is part of the reason why the coastal flood hazard zone in Anaura Bay is quite small relative to other areas.

Community wanted to know whether Anaura Bay is seen as being in a high risk of coastal flooding as the zone was calculated for this area. Councillor Seymour explains that the risk is no higher than it was a few months ago but that Council has the responsibility to use and communicate the information that resulted from Dr Gibb’s assessment. This information can be used to develop future land use in a way that makes it less sensitive to damage from coastal flooding.

Yvette Kinsella explains that currently any building in the area requires a building consent and often a resource consent. The Rivers & Land Drainage Team would like to have more certainty and data to base their decisions on.

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On top of that would this achieve more certainty for people wanting to build in the zone. The goal is not to change the existing buildings but to make building in the future safer.

The community members say that for them the risk of landslips from the hills is a lot higher than the risk of flooding from the sea. Especially the denuding of trees is a big concern. The risk seems to have increased since more roads were built. Currently, the community feels some protection from the trees but there is some concern about what would happen if these trees were cut down. Yvette Kinsella explains that for chopping the trees, permission is needed. To get the permission, the conservation team will check whether the chopping down is safe. There are strict rules for this process and usually only blocks of land are harvested at a time. Under special circumstances a notification will be published to which anyone can make a submission.

The community also mentions that not harvesting certain blocks would not have a large financial impact on the forestry organisations but would be important for the Anaura Bay community.

The major slip that occurred earlier this year has been planted and Council is currently looking at ways for drainage to get the water away.

Another concern is the warning system in case of a tsunami, especially due to the bad cell phone and radio coverage in Anaura Bay. Yvette Kinsella explains that wardens would go from door to door to inform the community.

Ideas for future building in the community include movable buildings and specified floor heights which let the water flow underneath the house. It is mentioned that this would be difficult in lower areas were floor heights of several meters would be needed. One community member notes that they were required to build their house with a certain floor height. The community member accepted the condition as it improved the safety of the building and did not add any extra costs, making it “worth the trouble”.

Yvette Kinsella mentions that it might also be possible to use lower levels of buildings for non-residential purposes such as a garage.

A member of the community mentions that she sees Anaura Bay as a unique community which is aware of the flood risk, with most people having lived there for many years. In her opinion, there is little development and not much changing-hands of land which leads to a very small risk of major subdivisions.

Another concern of the community is the erosion of the old graveyard. Yvette Kinsella and Katrin Markull will mention this issue to the Rivers & Land Drainage team.

The community in Tolaga Bay explains that they do not want to have too much restriction and regulation as this could “kill” the camp ground. Yvette Kinsella explains that the rules would also have benefits for land owners that want to build in the flood hazard zone as they would not be required to conduct an expensive hazard assessment themselves before being allowed to build in the zone.

The community members point out that the southern part of the CFHZ is an area which is important for the community’s economy and has the potential to grow in the future. Many of the reasons for Tolaga Bay’s existence are situated here, such as the Wharf and the camp ground. For this area, the community is keen to see long-term growth in the future. The northern part of the CFHZ is perceived to be less significant for Tolaga Bay and less development is expected to occur here. The community wants Council to be careful about putting regulations in that slow down the process of getting a building/resource consent. The processes are often too complicated, requiring several different reports and “ticking many boxes”.

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Councillor Seymour explains that it is Council’s responsibility to give the information it has on hazard zones to the community. She says the camp ground should be taken into account when setting up rules and suggests to have different conditions for temporary buildings. Yvette Kinsella mentions that making buildings movable might also be an option.

The community mentions that there is some concern for erosion of the dunes and the setting up of a dune care group is suggested. The community of Tolaga Bay is also welcome to join a dune care information meeting given by David Burgen from the Dunes Trust in Wainui in the end of October.

Another issue mentioned is the existence of mangroves in the estuary as mangroves have become a pest in other parts of New Zealand.

It is mentioned that the camp ground might extend to the North as land there has already been cleaned up and fenced off. Further north of the camp ground up to the river mouth, there is a DOC Site of Special interest (SSI). In the SSI there are many weeds and rabbits and the community would like to see DOC more active in pest control and maybe set up a management plan for the area.

The community points out that the area has a lot of potential and that there is no reason for the area not to grow. However, there are not many changes of hands of land and no high rise buildings to be expected in the future.

A plan to upgrade the parking area of the wharf and the shop of the camp ground is mentioned.

For the community, it is important that the rules do not involve “too much red tape” and engineering reports. There are already many different zones for one area of land which can make things complicated for the communities.

Concerns about flooding from rain which might damage the bridge on the main road one day through logs blocking up the river are mentioned. However, the community does not want to spend too much money on protection works (stop banks) as they perceive the loss of money in case of flooding to be smaller than the costs for improving the protection works.

3. Next Steps

Yvette Kinsella explains that the next step in the project will be to assess the different options in a cost-benefit analysis and to publish this assessment with the preferred option. The community then has the opportunity to make a submission and if necessary, a hearing will be organised.

ACTIONS:

Action Required Officer When

Talking to Rivers & Land Drainage team about concerns about graveyard erosion and problems of river water flowing off

Yvette Kinsella & Katrin Markull By 3 November

Sending the minutes Katrin Markull By 3 December

Scheduling a follow-up meeting Yvette Kinsella & Katrin Markull By 12 December

Katrin Markull Yvette Kinsella

Next Meeting: TBC

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