Civil Defence and Emergency Management Group Committee Meeting Held on 30/08/2017

Auckland Tsunami Community Exposure Analysis

R.J. Woods A. E. Lewis

GNS Science Consultancy Report 2017/74 May 2017

DISCLAIMER

This report has been prepared by the Institute of Geological and Nuclear Sciences Limited (GNS Science) exclusively for and under contract to Auckland Council. Unless otherwise agreed in writing by GNS Science, GNS Science accepts no responsibility for any use of or reliance on any contents of this report by any person other than Auckland Council and shall not be liable to any person other than Auckland Council, on any ground, for any loss, damage or expense arising from such use or reliance.

Use of Data: Date that GNS Science can use associated data: April 2017

BIBLIOGRAPHIC REFERENCE

Woods, R.J.; Lewis, A. E., 2017. Auckland Tsunami Community Exposure Analysis, GNS Science consultancy report 2017/74. 48 p.

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CONTENTS EXECUTIVE SUMMARY ...... IV 1.0 INTRODUCTION ...... 1 2.0 SCENARIOS ...... 2 2.1.1 Day and Night Scenarios ...... 2 2.1.2 Fine, Summer Day Scenario ...... 2 2.1.3 Tsunami Inundation Scenario ...... 2 3.0 METHODOLOGY ...... 5

3.1 IDENTIFICATION OF COMMUNITIES TO BE ASSESSED ...... 6 4.0 RESULTS ...... 9

4.1 LIMITATIONS OF MODELLED SCENARIOS ...... 10 5.0 DISCUSSION...... 11 6.0 ACKNOWLEDGEMENTS ...... 12 7.0 REFERENCES ...... 13

FIGURES

Figure 2.1 Auckland red and orange tsunami evacuation extents used in the exposure assessment...... 4 Figure 3.1 Example showing building locations used in the occupancy model...... 5 Figure 3.2 Figure showing the location of beach polygons (yellow lines) used to attribute populations for the daytime beach occupancy scenario...... 7 Figure 3.3 Figure depicting the extent of the Auckland Harbourside, Auckland Central West and Auckland Central East community outer limits...... 8

TABLES

Table 3.1 Beach class criteria used for the beach occupancy scenario...... 6 Table 4.1 The top twenty ranked exposed communities to tsunami in Auckland’s orange and red tsunami evacuation zones for the fine, summer day scenario...... 9

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APPENDICES A1.0 APPENDIX 1: SUMMARY OF RESULTS RANKED BY HIGHEST EXPOSURE ...... 15 A2.0 APPENDIX 2: INDICATIVE MAPS SHOWING LOCATIONS OF COMMUNITIES USED IN THE EXPOSURE ASSESSMENT ...... 21 A3.0 APPENDIX 3: DETAILED RANKED EXPOSURE RESULTS FOR COMMUNITES THAT INTERSECT THE ORANGE AND RED TSUNAMI EVACUATION ZONES FOR THE FINE, SUMMERS DAY SCENARIO...... 41

APPENDIX FIGURES

Figure A2.1 Map of communities for Auckland’s north-eastern coast including Kawau Island. Blue lines indicate community boundaries...... 21 Figure A2.2 Map of communities for Auckland’s north-eastern coast including Whangaparaoa Peninsula. Blue lines indicate community boundaries...... 22 Figure A2.3 Map of communities for Auckland’s North Shore. Blue lines indicate community boundaries...... 23 Figure A2.4 Map of communities for Auckland’s northern Waitematā Harbour and Devonport. Blue lines indicate community boundaries...... 24 Figure A2.5 Map of communities for Waiheke Island. Blue lines indicate community boundaries. .... 25 Figure A2.6 Map of communities for the northern extent of the Waitematā Harbour. Blue lines indicate community boundaries...... 26 Figure A2.7 Map of communities for the southern extent of the Waitematā Harbour. Blue lines indicate community boundaries...... 27 Figure A2.8 Map of communities for Ōrākei and western Tamāki Strait. Blue lines indicate community boundaries...... 28 Figure A2.9 Map of communities for southern Tamāki Strait. Blue lines indicate community boundaries...... 29 Figure A2.10 Map of communities for eastern Tamāki Strait and Howick. Blue lines indicate community boundaries...... 30 Figure A2.11 Map of communities for Beachlands and Clevedon. Blue lines indicate community boundaries...... 31 Figure A2.12 Map of communities for Kawakawa Bay and Orere Point. Blue lines indicate community boundaries...... 32 Figure A2.13 Map of communities for Great Barrier Island. Blue lines indicate community boundaries...... 33 Figure A2.14 Map of communities for south Kaipara Harbour and northern west coast. Blue lines indicate community boundaries...... 34 Figure A2.15 Map of communities for Auckland’s west coast, north of the Manukau Harbour. Blue lines indicate community boundaries...... 35 Figure A2.16 Map of communities for the northern Manukau Harbour. Blue lines indicate community boundaries...... 36 Figure A2.17 Map of communities for the north-eastern Manukau Harbour. Blue lines indicate community boundaries...... 37

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Figure A2.18 Map of communities for the south-eastern Manukau Harbour. Blue lines indicate community boundaries...... 38 Figure A2.19 Map of communities for the southern Manukau Harbour. Blue lines indicate community boundaries...... 39 Figure A2.20 Map of communities for the Awhitu Peninsula. Blue lines indicate community boundaries...... 40

APPENDIX TABLES

Table A3.1 Ranked exposure results for each Auckland community, by Local Board Area, that intersect the orange and red tsunami evacuation zones for the fine, summers day scenario...... 41

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EXECUTIVE SUMMARY

Three scenarios, day, night and fine summers day, have been modelled to identify which Auckland communities have the greatest population exposure in the region’s orange and red tsunami evacuation areas. We consider that a worst-case exposure scenario would occur when peak tsunami waves coincide with a fine, summers day and have adopted this as the selected scenario to inform the prioritisation of communities.

Based on the modelled scenario, the community with the highest exposure is Orewa with 6,521 people within the evacuation areas modelled (Appendix 1). Orewa is substantially higher than other communities and is followed by Browns Bay with 3,597 people exposed. There is a total of 22,913 exposed in the top ten ranked communities and 31,798 people exposed in the top twenty. For all 217 communities that are exposed, there is a total of 49,853 exposed in the orange and red evacuation zones for this scenario.

The study ranks Auckland communities with the greatest tsunami exposure for selected inundation zones. The adopted scenario represents a situation where a higher proportion of the Auckland community would be located in low lying coastal areas. If tsunami waves were to affect the Auckland coast under these conditions more people would be exposed to the hazard than for other modelled scenarios. As such, we would recommend the use of the fine summers day scenario results to prioritise community engagement activities for potential tsunami public alerting solutions.

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1.0 INTRODUCTION

Auckland Civil Defence and Emergency Management (CDEM) are seeking to better understand the exposure of Auckland communities to tsunami inundation. To prioritise local board engagement activities regarding future tsunami public alerting options, Auckland CDEM require an assessment of the exposed population located within the Auckland orange and red tsunami evacuation zones.

To determine which communities have the highest exposure, occupancy models, previously developed for RiskScape, were used for three preselected scenarios. These scenarios modelled people exposure for a typical day, a typical night and a fine, summers day to identify a ‘worst-case’ scenario. We present results of communities with the highest ranked exposure to tsunamis which could inundate the mapped orange and red evacuation areas. It is intended that the results of this analysis will form the basis for discussions with decision-makers on the practical rollout of future public alerting options in Auckland.

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2.0 SCENARIOS

The number of people, in any particular community who are exposed to tsunamis, depends on a range of variables. These include whether the tsunami arrives during the day, when a large part of the population is at work, or at night, when large parts of the population are in bed, at home, asleep. In addition, the number of people occupying low lying coastal areas can vary throughout the year, with more recreational activities on beaches during summer; and can be weather dependent, with more beach visitors likely during periods of fine weather.

To understand how this variability changes in Auckland, three scenarios were modelled to capture day/night variation and an increased number of people on beaches within selected tsunami evacuation zones. We consider that a worst-case exposure scenario would occur when peak tsunami waves coincide with a fine summer’s day and have adopted this as the selected scenario to inform the prioritisation of communities.

2.1.1 Day and Night Scenarios

The variation between day and night population exposure can be used to inform community specific assessments such as, detailed evacuation and emergency response planning. The model used to determine how populations change between day and night in Auckland is detailed in GNS Science Report 2013/52 (Cousins, 2015). In summary, the daytime scenario represents a workday snapshot, defined as 11 a.m. which is assumed to be the time of the working day when most workers will be indoors at work. The time of the night scenario is assumed to be 2 a.m., which is when most people are likely to be in bed, at home, asleep (Cousins, 2013).

2.1.2 Fine, Summer Day Scenario

The fine, summer day scenario was developed to model a ‘worst-case’ exposure scenario, where a higher proportion of the Auckland community would be located in low lying coastal areas. If tsunami waves were to affect the Auckland coast under these conditions, more people would be exposed to the hazard than for the other modelled scenarios. This scenario uses a modified version of the daytime population model, to represent a fine summer day, where many people would be visiting the region’s beaches.

2.1.3 Tsunami Inundation Scenario

The tsunami inundation scenario used in this assessment is based on Auckland’s existing orange and red tsunami evacuation zones (Figure 2.1). These two zones represent the low- lying coastal areas where people are exposed to more frequent tsunami events, not the maximum-credible, infrequent events.

The Auckland tsunami evacuation zones are separated into three areas; red, orange and yellow. The red evacuation zone maps the beaches and very low-lying coastal areas and provides a guide for those areas which should be evacuated if a Marine and Beach Threat Warning (MCDEM, 2012) is issued. The orange evacuation zone maps the maximum inundation extent of a three metre, at coast, wave. This zone provides a guide for those areas which should be evacuated if a 1 to 3 metre, Marine and Land Threat Warning (MCDEM, 2012) is issued. The yellow evacuation zone maps the maximum inundation extent for a maximum credible tsunami event. For Auckland, this equates to a greater than magnitude 9 earthquake on the Tonga-Kermadec trench which has an estimated average return period of around 2,500 years (Barberopoulou, 2013).

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The red tsunami evacuation zone represents the highest risk zone and is the first area people should evacuate from in all types of tsunami warnings (MCDEM, 2016). All of Auckland’s beaches fall within the red zone. The orange tsunami evacuation zone includes the range of tsunami scenarios, from both distant and regional sources, that could generate wave heights of up to three metres anywhere on the Auckland coast (Leonard, 2012). For context, on average, a 3 metre, at coast, tsunami wave has a return period of around 100 to 300 years on Auckland’s mainland east coast (Power, 2013).

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Figure 2.1 Auckland red and orange tsunami evacuation extents used in the exposure assessment.

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3.0 METHODOLOGY

A Geographic Information Systems (GIS) based analysis was used to calculate the number of exposed residents in communities. Building datasets and occupancy rate models, previously created through the GNS Science and National Institute Water and Atmospheric (NIWA) Ltd joint RiskScape1 programme, were used to identify each community’s resident population (Cousins, 2015). The occupancy model used resident population statistics from the 2013 census and distributed the population across buildings (Figure 3.1) depending on whether it is day or night. Using this approach, the number of exposed resident populations were determined for each of these scenarios.

Figure 3.1 Example showing building locations used in the occupancy model.

While the variation between day and night populations was assessed, these scenarios do not count people located outside of buildings, in particular those visiting beaches (Cousins, 2015). Therefore, the daytime model was modified to include people distributed across 316 Auckland beaches (Figure 3.2) using the criteria presented in Table 3.1. Using this new distribution of residents and increased beach occupation, the proportion of people exposed to tsunamis in the orange and red evacuation zones was determined.

1 RiskScape software was not required to be used for the exposure assessment.

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Table 3.1 Beach class criteria used for the beach occupancy scenario.

Beach Class Occupancy Rate Length per Description Auckland Examples (exposure) (persons/km) Person (m)

Low 1 1,000 Isolated beaches Awhitu, South Head, Whangapoua Beach

Medium 10 100 Beaches used for Kawakawa Bay, Te activities such as diving, Haruhi Bay, Okoromai fishing, walking Bay

High 100 10 Surfing and swimming Eastern Beach, beaches Bucklands Beach

Very High 330 3 High use crowded Mission Bay, Takapuna beaches Beach, Long Bay, Omaha

3.1 IDENTIFICATION OF COMMUNITIES TO BE ASSESSED

Communities boundaries were based on the Auckland census-unit areas (suburbs) layer. This layer was manually edited to refine some smaller communities using map data provided by Auckland CDEM in March 2017. Only those that intersect the orange and red tsunami evacuation zones are presented in the results, therefore these do not provide a comprehensive list of Auckland suburbs. Communities used in the analysis are depicted in indicative maps2 shown in Appendix 2 and listed by Local Board area in Appendix 3.

As the population model is based on building location, buildings may have been counted twice resulting in possible duplication of the exposed population in these communities. The proportion of these buildings is negligible at 0.15% of the entire dataset. The intersection of buildings with community boundaries is most common where high density residential areas coincide with red and orange tsunami evacuation zones.

Due to the variable range of visitors within the Auckland Central Business District (CBD) we recommend that this area is subjected to a more intensive, specific exposure analysis outside of the scope of this assessment. Therefore, the suburbs of Auckland Harbourside, Auckland Central West and Auckland Central East (Figure 3.3) have not been included in the analysis. These communities were excluded due to multi-storey buildings that could have the potential for vertical evacuation. In addition, they have a substantial transient, non-resident population with many people located in inner-city restaurants, bars and hotels and a high frequency of seasonal tourists via cruise ships.

2 Specific community boundaries are provided in a GIS file accompanying this report and can be obtained by requesting these from Auckland Civil Defence and Emergency Management.

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Figure 3.2 Figure showing the location of beach polygons (yellow lines) used to attribute populations for the daytime beach occupancy scenario.

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Figure 3.3 Figure depicting the extent of the Auckland Harbourside, Auckland Central West and Auckland Central East community outer limits.

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4.0 RESULTS

The detailed results of the ‘worst-case’ fine, summer day scenario ranked by each community’s exposure and respective Local Board Area are presented in Appendix 3. Table 4.1 lists the top twenty communities with the highest exposure in the orange and red tsunami evacuation areas for this scenario.

Based on the modelled scenario, the community with the highest exposure is Orewa with 6,521 people within the evacuation areas modelled. Orewa is substantially higher than other communities and is followed by Browns Bay with 3,597 people exposed. There is a total of 22,913 exposed in the top ten ranked communities and 31,798 people exposed in the top twenty. For all 216 communities modelled, there is a total of 49,853 people in the orange and red evacuation zones for this scenario.

Table 4.1 The top twenty ranked exposed communities to tsunami in Auckland’s orange and red tsunami evacuation zones for the fine, summer day scenario.

Rank Community Local Board Area Exposed Population

1 Orewa Hibiscus and Bays 6521

2 Browns Bay Hibiscus and Bays 3597

3 Omaha Rodney 2327

4 Mt Victoria Devonport – Takapuna 1969

5 Paremoremo West Rodney 1702

6 Stanley Bay Devonport – Takapuna 1668

7 Silverdale Central Hibiscus and Bays 1543

8 Te Henga Waitakere Ranges 1243

9 Stanmore Bay East Hibiscus and Bays 1236

10 Edgewater Howick 1107

11 Mt Wellington South Maungakiekie - Tamāki 968

12 Takapuna Central Devonport – Takapuna 964

13 Glen Innes East Maungakiekie - Tamāki 957

14 Eastern Beach Howick 932

15 Onetangi Waiheke 905

16 Lake Pupuke Devonport – Takapuna 904

17 Mairangi Bay Hibiscus and Bays 891

18 Mission Bay Ōrākei 842

19 Maraetai Franklin 777

20 Helensville Rodney 745

Using monthly regional park visitor data, provided by Auckland Council, a comparison of the results for Long Bay Regional Park was used to provide a calibration for this scenario. Between June 2014 and June 2016, the highest visitor frequency occurred in January 2015 with 156,211 visits. This month is considered to be representative of a period of high beach occupancy at 204% of the monthly average for the two years.

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For the duration of the month very little rainfall was recorded and sunshine hours were high, averaging 10.73 hours per day (NIWA, 2017). Using these figures to average beach occupancy across the month it could be expected that, on average, 470 people would be visiting the beach at any given daylight hour. This figure compares well with the 420 people quantified using the adapted occupancy model (Appendix 3). It is recognised that beach visitation is not distributed evenly throughout the day however we consider this to be a reasonable regional approximation for calibration.

4.1 LIMITATIONS OF MODELLED SCENARIOS

This analysis has provided a representative assessment of Auckland’s tsunami population exposure based on three scenarios. The following assumptions and/or limitations have been employed in this assessment: • The assessment is based on the proportion of people located within the Auckland orange and red tsunami evacuation areas and does not include the movement or evacuation of people due to natural, informal or official tsunami warnings. • The analysis has excluded the communities of Auckland Harbourside, Auckland Central West and Auckland Central East. These communities were excluded due to multi-storey buildings that could have the potential for vertical evacuation. In addition, they have a substantial transient, non-resident population with many people located in inner-city restaurants, bars and hotels and a high frequency of seasonal tourists via cruise ships. We recommend that the complexity of these three communities warrants a separate analysis to this regional assessment. • The analysis does not include people at sea, in the Hauraki Gulf or on Department of Conservation managed islands (excluding those included in the fine, summer day scenario). • The analysis does not include people situated on transport networks, such as State Highways, located in the orange and red tsunami evacuation zones.

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5.0 DISCUSSION

Three scenarios, day, night and fine summers day, have been modelled to identify which Auckland communities have the greatest population exposure in Auckland’s orange and red tsunami evacuation areas. We consider that a worst-case exposure scenario would occur when peak tsunami waves coincide with a fine summers day and have adopted this as the selected scenario to inform the prioritisation of communities.

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6.0 ACKNOWLEDGEMENTS

The report has been reviewed by Graham Leonard, Maureen Coomer and Hannah Brackley of GNS Science, who are thanked for their helpful input. Reviews and assistance with data provision from Auckland Civil Defence and Emergency Management team members Celia Wilson, Hamish Keith and Craig Glover have been greatly appreciated.

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7.0 REFERENCES Barberopoulou, A. 2013. A GIS-based tsunami inundation area for the Maximum Credible Wave Height in Auckland. GNS Science Letter Report 2013/240 to Auckland Council, Lower Hutt. 7p.

Cousins, W. J. 2013. Occupancy Model for RiskScape, GNS Science Report 2013/52. 25p. Leonard, G.L. 2012. An initial GIS-based tsunami inundation area for a three metre wave height in Auckland. GNS Science Letter Report 2012/208 to Auckland Council, Lower Hutt. 5p.

Ministry of Civil Defence and Emergency Management (MCDEM) 2012. Tsunami Advisory and Warning Plan [SP 01/09]. MCDEM, Wellington. 70p.

Ministry of Civil Defence and Emergency Management (MCDEM) 2016. Tsunami Evacuation Zones: Director’s Guideline for Civil Defence Emergency Management Groups [DGL 08/16]. MCDEM, Wellington. 39p.

National Institute of Water and Atmospheric Research (NIWA), 2017. Site; NIWA EWS 37852, data accessed on 20 April 2017 from https://cliflo.niwa.co.nz Power, W.L. 2013. Tsunami hazard curves and deaggregation plots for 20km coastal sections, derived from the 2013 National Tsunami Hazard Model, GNS Science Report 2013/59. 547p.

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APPENDICES

A1.0 APPENDIX 1: SUMMARY OF RESULTS RANKED BY HIGHEST EXPOSURE

Rank Community Local Board Area Exposed Population

1 Orewa Hibiscus and Bays 6521

2 Browns Bay Hibiscus and Bays 3597

3 Omaha Rodney 2327

4 Mt Victoria Devonport - Takapuna 1969

5 Paremoremo West Rodney 1702

6 Stanley Bay Devonport - Takapuna 1668

7 Silverdale Central Hibiscus and Bays 1543

8 Te Henga Waitakere Ranges 1243

9 Stanmore Bay East Hibiscus and Bays 1236

10 Edgewater Howick 1107

11 Mt Wellington South Maungakiekie - Tamaki 968

12 Takapuna Central Devonport - Takapuna 964

13 Glen Innes East Maungakiekie - Tamaki 957

14 Eastern Beach Howick 932

15 Onetangi Waiheke 905

16 Lake Pupuke Devonport - Takapuna 904

17 Mairangi Bay Hibiscus and Bays 891

18 Mission Bay Orakei 842

19 Maraetai Franklin 777

20 Helensville Rodney 745

21 Big Manly Hibiscus and Bays 722

22 Kohimarama West Orakei 711

23 St Heliers Orakei 688

24 Piha Waitakere Ranges 687

25 Bucklands Beach Howick 668

26 Muriwai Rodney 562

27 Onehunga Maungakiekie - Tamaki 526

28 South Head Rodney 521

29 Long Bay Hibiscus and Bays 421

30 Chelsea Kaipatiki 412

31 Kingdale Henderson - Massey 396

32 Army Bay Hibiscus and Bays 388

33 Claris Great Barrier 384

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Rank Community Local Board Area Exposed Population

34 Narrow Neck Devonport - Takapuna 374

35 Northcote South Kaipatiki 368

36 Mangere Bridge Mangere - Otahuhu 327

37 St Marys Waitemata 317

38 Gulf Harbour Hibiscus and Bays 314

39 Westlake Devonport - Takapuna 294

40 Waiwera Hibiscus and Bays 289

41 Little Manly Hibiscus and Bays 283

42 Snells Beach Rodney 270

43 Mangere South Mangere - Otahuhu 244

44 Otahuhu East Mangere - Otahuhu 239

45 Palm Beach Waiheke 239

46 Wade Heads Hibiscus and Bays 225

47 Kawakawa Bay Franklin 214

48 Point Wells Rodney 208

49 Red Beach East Hibiscus and Bays 203

50 Orere Point Franklin 200

51 Mellons Bay Howick 195

52 Orakei North Orakei 190

53 Torbay Hibiscus and Bays 189

54 Parakai Urban Rodney 168

55 Ostend Waiheke 166

56 Swann Beach Hibiscus and Bays 164

57 Surfdale Waiheke 162

58 Seacliffe Devonport - Takapuna 158

59 Half Moon Bay Howick 153

60 Beachlands Franklin 151

61 Awhitu Franklin 151

62 Pakiri Rodney 149

63 Murrays Bay Hibiscus and Bays 138

64 Lucken Point Upper Harbour 137

65 Hauraki Devonport - Takapuna 136

66 Tryphena Great Barrier 130

67 Okiwi Great Barrier 127

68 Sunnyhills Howick 119

69 Lynnmall Whau 116

70 Tamaki Maungakiekie - Tamaki 110

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Rank Community Local Board Area Exposed Population

71 Farm Cove Howick 106

72 Omaha Flats Rodney 106

73 Martins Bay Rodney 98

74 Remuera West Orakei 97

75 Bayswater Devonport - Takapuna 96

76 Tawharanui Peninsula Rodney 92

77 Kawakawa-Orere Franklin 91

78 Campbells Bay Hibiscus and Bays 89

79 Orakei South Orakei 89

80 Hatfields Beach Hibiscus and Bays 87

81 Glen Innes North Orakei 87

82 Cockle Bay Howick 86

83 Panmure Basin Maungakiekie - Tamaki 86

84 Tauhoa-Puhoi Rodney 83

85 Matakatia Bay Hibiscus and Bays 82

86 Kawau Island Rodney 74

87 Tuff Crater Kaipatiki 64

88 Waitaramoa Rodney 63

89 Point England Maungakiekie - Tamaki 59

90 Herald Island Upper Harbour 59

91 Great Barrier Island Great Barrier 56

92 Kohimarama East Orakei 56

93 Laingholm Waitakere Ranges 56

94 Waiake Hibiscus and Bays 54

95 Glendowie Orakei 48

96 Algies Bay Rodney 47

97 Karekare Waitakere Ranges 45

98 Cape Rodney South Rodney 43

99 Castor Bay Devonport - Takapuna 41

100 Whangateau Rodney 41

101 Clevedon Rodney 40

102 Titirangi South Waitakere Ranges 39

103 Rothesay Bay Hibiscus and Bays 38

104 Fairburn Mangere - Otahuhu 37

105 Parakai Rural Rodney 36

106 Crown Hill Devonport - Takapuna 35

107 Medlands Beach Great Barrier 35

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Rank Community Local Board Area Exposed Population

108 Ambury Mangere - Otahuhu 35

109 Greenhithe Upper Harbour 35

110 Te Papapa Maungakiekie - Tamaki 34

111 Durham Green Henderson - Massey 33

112 Grange Otara - Papatoetoe 33

113 Te Arai Rodney 32

114 Rewiti Rodney 31

115 Westmere Waitemata 31

116 Oneroa Waiheke 27

117 Cape Rodney Rodney 26

118 Favona North Mangere - Otahuhu 23

119 Favona South Mangere - Otahuhu 23

120 Blackpool Waiheke 23

121 Point Chevalier East Albert - Eden 22

122 Rongomai Otara - Papatoetoe 22

123 New Lynn North Whau 22

124 Ti Point Rodney 21

125 Orapiu Waiheke 21

126 Point Chevalier South Albert - Eden 20

127 Stanmore Bay West Hibiscus and Bays 20

128 Mahurangi West Rodney 19

129 Papakura North Papakura 18

130 Kaikoura and Rangiahua Great Barrier 16 Islands

131 Wakeling Henderson - Massey 16

132 Big Bay Franklin 15

133 Whitford Rodney 15

134 Edmonton Henderson - Massey 14

135 Avondale West Whau 14

136 Kingseat Franklin 13

137 Howick Beach Howick 13

138 Mangere Mangere - Otahuhu 13

139 Mahurangi Rodney 13

140 Glendene South Whau 13

141 Mcleod Henderson - Massey 12

142 Awana Great Barrier 11

143 Matipo Henderson - Massey 11

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Rank Community Local Board Area Exposed Population

144 Stillwater Hibiscus and Bays 11

145 Green Bay Whau 11

146 Shelly Park Howick 10

147 Paremoremo East Upper Harbour 10

148 Glenavon Whau 10

149 Otahuhu West Mangere - Otahuhu 9

150 Fairdene Henderson - Massey 8

151 Birkenhead East Kaipatiki 7

152 Red Beach West Hibiscus and Bays 6

153 Vipond Hibiscus and Bays 6

154 Wymondley Otara - Papatoetoe 6

155 Waima Waitakere Ranges 6

156 Otahuhu North Mangere - Otahuhu 5

157 Waterview Albert - Eden 4

158 Te Atatu Central Henderson - Massey 4

159 Bucklands Beach South Howick 4

160 Matheson Bay Rodney 4

161 Kaukapakapa Rural Rodney 4

162 Henderson North Henderson - Massey 3

163 Silverdale North Hibiscus and Bays 3

164 Harania East Mangere - Otahuhu 3

165 Armour Bay Waitakere Ranges 3

166 Puketu Island Mangere - Otahuhu 2

167 Meadowbank North Orakei 2

168 Omiha Waiheke 2

169 Roberton Whau 2

170 Kelston Central Whau 2

171 Herald Upper Harbour 1

172 Hobsonville East Upper Harbour 1

173 Waiheke Island Waiheke 1

174 Parnell West Waitemata 1

175 Rosebank Albert - Eden 0

176 Point Chevalier West Albert - Eden 0

177 Port Fitzroy Great Barrier 0

178 Whangaparapara Great Barrier 0

179 Royal Heights Henderson - Massey 0

180 Birdwood East Henderson - Massey 0

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Rank Community Local Board Area Exposed Population

181 Weiti River Hibiscus and Bays 0

182 Manly Hibiscus and Bays 0

183 Silverdale South Hibiscus and Bays 0

184 Awaruku Hibiscus and Bays 0

185 Glamorgan Hibiscus and Bays 0

186 Dairy Flat-Redvale Hibiscus and Bays 0

187 Pakuranga Central Howick 0

188 Elsmore Park Howick 0

189 Burswood Howick 0

190 Pakuranga East Howick 0

191 Golfland Howick 0

192 Highland Park Howick 0

193 Bleakhouse Howick 0

194 Pakuranga North Howick 0

195 Ocean View Kaipatiki 0

196 Harania North Mangere - Otahuhu 0

197 Harania Mangere - Otahuhu 0

198 Glen Innes West Maungakiekie - Tamaki 0

199 Hobsonville East Maungakiekie - Tamaki 0

200 Penrose Maungakiekie - Tamaki 0

201 Waiata Orakei 0

202 Highbrook Otara - Papatoetoe 0

203 Otara Otara - Papatoetoe 0

204 Middlemore Otara - Papatoetoe 0

205 Ferguson Otara - Papatoetoe 0

206 Mangere East Otara - Papatoetoe 0

207 Hobsonville South Puketapapa 0

208 Warkworth Rodney 0

209 Matakana Rodney 0

210 Leigh Rodney 0

211 Waimumu South Rodney 0

212 Starling Park Waitakere Ranges 0

213 Freemans Bay Waitemata 0

214 Herne Bay Waitemata 0

215 Ponsonby West Waitemata 0

216 Glendene North Whau 0

217 Avondale South Whau 0

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A2.0 APPENDIX 2: INDICATIVE MAPS SHOWING LOCATIONS OF COMMUNITIES USED IN THE EXPOSURE ASSESSMENT

Figure A2.1 Map of communities for Auckland’s north-eastern coast including Kawau Island. Blue lines indicate community boundaries.

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Figure A2.2 Map of communities for Auckland’s north-eastern coast including Whangaparaoa Peninsula. Blue lines indicate community boundaries.

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Figure A2.3 Map of communities for Auckland’s North Shore. Blue lines indicate community boundaries.

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Figure A2.4 Map of communities for Auckland’s northern Waitematā Harbour and Devonport. Blue lines indicate community boundaries.

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Figure A2.5 Map of communities for Waiheke Island. Blue lines indicate community boundaries.

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Figure A2.6 Map of communities for the northern extent of the Waitematā Harbour. Blue lines indicate community boundaries.

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Figure A2.7 Map of communities for the southern extent of the Waitematā Harbour. Blue lines indicate community boundaries.

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Figure A2.8 Map of communities for Ōrākei and western Tamāki Strait. Blue lines indicate community boundaries.

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Figure A2.9 Map of communities for southern Tamāki Strait. Blue lines indicate community boundaries.

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Figure A2.10 Map of communities for eastern Tamāki Strait and Howick. Blue lines indicate community boundaries.

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Figure A2.11 Map of communities for Beachlands and Clevedon. Blue lines indicate community boundaries.

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Figure A2.12 Map of communities for Kawakawa Bay and Orere Point. Blue lines indicate community boundaries.

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Figure A2.13 Map of communities for Great Barrier Island. Blue lines indicate community boundaries.

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Figure A2.14 Map of communities for south Kaipara Harbour and northern west coast. Blue lines indicate community boundaries.

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Figure A2.15 Map of communities for Auckland’s west coast, north of the Manukau Harbour. Blue lines indicate community boundaries.

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Figure A2.16 Map of communities for the northern Manukau Harbour. Blue lines indicate community boundaries.

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Figure A2.17 Map of communities for the north-eastern Manukau Harbour. Blue lines indicate community boundaries.

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Figure A2.18 Map of communities for the south-eastern Manukau Harbour. Blue lines indicate community boundaries.

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Figure A2.19 Map of communities for the southern Manukau Harbour. Blue lines indicate community boundaries.

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Figure A2.20 Map of communities for the Awhitu Peninsula. Blue lines indicate community boundaries.

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A3.0 APPENDIX 3: DETAILED RANKED EXPOSURE RESULTS FOR COMMUNITES THAT INTERSECT THE ORANGE AND RED TSUNAMI EVACUATION ZONES FOR THE FINE, SUMMERS DAY SCENARIO

Table A3.1 Ranked exposure results for each Auckland community, by Local Board Area, that intersect the orange and red tsunami evacuation zones for the fine, summers day scenario.

Day Population Day Population Total Daytime Exposure Community (Orange Zone) (Red Zone) Population Rank Albert - Eden Local Board

Point Chevalier East 22 - 22 121

Point Chevalier South 20 - 20 126

Waterview 4 - 4 157 Devonport - Takapuna Local Board

Mt Victoria 1604 365 1969 4

Stanley Bay 1658 10 1668 6

Takapuna Central 107 857 964 12

Lake Pupuke 533 371 904 16

Narrow Neck 212 162 374 34

Westlake 294 - 294 39

Seacliffe 24 134 158 58

Hauraki 136 - 136 65

Bayswater 77 19 96 75

Castor Bay 41 - 41 99

Crown Hill 35 - 35 106 Franklin Local Board

Maraetai 55 722 777 19

Kawakawa Bay 148 66 214 47

Orere Point - 200 200 50

Beachlands 38 113 151 60

Awhitu - 151 151 61

Kawakawa-Orere - 91 91 77

Big Bay - 15 15 132

Kingseat - 13 13 136

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Day Population Day Population Total Daytime Exposure Community (Orange Zone) (Red Zone) Population Rank Great Barrier Local Board

Claris 9 375 384 33

Tryphena 96 34 130 66

Okiwi 2 125 127 67

Great Barrier Island - 56 56 91

Medlands Beach 15 20 35 107

Kaikoura & Rangiahua - 16 16 130

Awana - 11 11 142 Henderson - Massey Local Board

Kingdale 396 - 396 31

Durham Green 33 - 33 111

Wakeling 16 - 16 131

Edmonton 14 - 14 134

Mcleod 12 - 12 141

Matipo 11 - 11 143

Fairdene 8 - 8 150

Te Atatu Central 4 - 4 158

Henderson North 3 - 3 162

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Day Population Day Population Total Daytime Exposure Community (Orange Zone) (Red Zone) Population Rank Hibiscus and Bays Local Board

Orewa 5664 857 6521 1

Browns Bay 3151 446 3597 2

Silverdale Central 1543 - 1543 7

Stanmore Bay East 323 913 1236 9

Mairangi Bay 451 440 891 17

Big Manly 416 306 722 21

Long Bay 1 420 421 29

Army Bay 15 373 388 32

Gulf Harbour 313 1 314 38

Waiwera 282 7 289 40

Little Manly 283 - 283 41

Wade Heads 134 91 225 46

Red Beach East 203 - 203 49

Torbay 189 - 189 53

Swann Beach 38 126 164 56

Murrays Bay 70 68 138 63

Campbells Bay 89 - 89 78

Hatfields Beach 15 72 87 80

Matakatia Bay 30 52 82 82

Waiake 51 3 54 94

Rothesay Bay 38 - 38 103

Stanmore Bay West 20 - 20 127

Stillwater 11 - 11 144

Red Beach West 6 - 6 152

Vipond 6 - 6 153

Silverdale North 3 - 3 163

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Day Population Day Population Total Daytime Exposure Community (Orange Zone) (Red Zone) Population Rank

Howick Local Board

Edgewater 1107 - 1107 10

Eastern Beach 572 360 932 14

Bucklands Beach 380 288 668 25

Mellons Bay 3 192 195 51

Half Moon Bay 153 - 153 59

Sunnyhills 118 1 119 68

Farm Cove 106 - 106 71

Cockle Bay 39 47 86 82

Howick Beach 13 - 13 137

Shelly Park 10 - 10 146

Bucklands Beach 4 - 4 159 South

Kaipātiki Local Board

Chelsea 412 - 412 30

Northcote South 323 45 368 35

Tuff Crater 64 - 64 87

Birkenhead East - 7 7 151

Māngere - Ōtāhuhu Local Board

Māngere Bridge 327 - 327 36

Māngere South 244 - 244 43

Ōtāhuhu East 239 - 239 44

Fairburn 37 - 37 104

Ambury 35 - 35 108

Favona North 23 - 23 118

Favona South 23 - 23 119

Māngere 13 - 13 138

Ōtāhuhu West 9 - 9 149

Ōtāhuhu North 5 - 5 156

Harania East 3 - 3 164

Puketu Island 2 - 2 166

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Day Population Day Population Total Daytime Exposure Community (Orange Zone) (Red Zone) Population Rank

Maungakiekie - Tamāki Local Board

Mt Wellington South 968 - 968 11

Glen Innes East 957 - 957 13

Onehunga 525 1 526 27

Tamāki 90 20 110 70

Panmure Basin 82 4 86 83

Point England 59 - 59 89

Te Papapa 34 - 34 110

Ōrākei Local Board

Mission Bay 612 230 842 18

Kohimarama West 401 310 711 22

St Heliers 573 115 688 23

Ōrākei North 88 102 190 52

Remuera West 97 - 97 74

Ōrākei South 89 - 89 79

Glen Innes North 87 - 87 81

Kohimarama East 56 - 56 92

Glendowie 48 - 48 95

Meadowbank North - 2 2 167

Ōtara - Papatoetoe Local Board

Grange 33 - 33 112

Rongomai 22 - 22 122

Wymondley 6 - 6 152

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Day Population Day Population Total Daytime Exposure Community (Orange Zone) (Red Zone) Population Rank

Papakura Local Board

Papakura North 18 - 18 129

Rodney Local Board

Omaha 464 1863 2327 3

Paremoremo West 1702 - 1702 5

Helensville 738 7 745 20

Muriwai - 562 562 26

South Head - 521 521 28

Snells Beach 101 169 270 42

Point Wells 208 - 208 48

Parakai Urban 168 - 168 54

Pakiri 6 143 149 62

Omaha Flats 106 - 106 72

Martins Bay 8 90 98 73

Tawharanui Peninsula 6 86 92 76

Tauhoa-Puhoi 16 67 83 84

Kawau Island 37 37 74 86

Algies Bay 47 - 47 96

Cape Rodney South 34 9 43 98

Whangateau 41 - 41 100

Clevedon 1 39 40 105

Parakai Rural 36 - 36 101

Te Arai - 32 32 113

Rewiti - 31 31 114

Cape Rodney - 26 26 117

Ti Point - 21 21 124

Mahurangi West 11 8 19 128

Whitford 15 - 15 133

Mahurangi 10 3 13 139

Matheson Bay 1 3 4 160

Kaukapakapa Rural 1 3 4 161

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Day Population Day Population Total Daytime Exposure Community (Orange Zone) (Red Zone) Population Rank

Upper Harbour Local Board

Lucken Point 137 - 137 64

Herald Island 59 - 59 90

Greenhithe - 35 35 109

Paremoremo East 10 - 10 147

Herald - 1 1 171

Hobsonville East - 1 1 172 Waiheke Local Board

Onetangi 118 787 905 15

Palm Beach 40 199 239 45

Ostend 165 1 166 55

Surfdale 162 - 162 57

Oneroa 26 1 27 116

Blackpool 21 2 23 120

Orapiu - 21 21 125

Omiha 2 - 2 168

Waiheke Island - 1 1 173 Waitākere Ranges Local Board

Te Henga 10 1233 1243 8

Piha 43 644 687 24

Laingholm 42 14 56 93

Karekare 45 - 45 97

Titirangi South 8 31 39 102

Waima 6 - 6 155

Armour Bay - 3 3 165

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Day Population Day Population Total Daytime Exposure Community (Orange Zone) (Red Zone) Population Rank Waitematā Local Board

St Marys 171 146 317 37

Westmere 31 - 31 115

Parnell West - 1 1 174 Whau Local Board

Lynnmall 116 0 116 69

New Lynn North 22 - 22 123

Avondale West 14 - 14 135

Glendene South 13 - 13 140

Green Bay - 11 11 145

Glenavon 10 - 10 148

Roberton 2 - 2 169

Kelston Central 2 - 2 170

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Principal Location Other Locations

1 Fairway Drive Dunedin Research Centre Wairakei Research Centre National Isotope Centre Avalon 764 Cumberland Street 114 Karetoto Road 30 Gracefield Road PO Box 30368 Private Bag 1930 Wairakei PO Box 31312 Lower Hutt Dunedin Private Bag 2000, Taupo Lower Hutt New Zealand New Zealand New Zealand New Zealand T +64-4-570 1444 T +64-3-477 4050 T +64-7-374 8211 T +64-4-570 1444 www.gns.cri.nz F +64-4-570 4600 F +64-3-477 5232 F +64-7-374 8199 F +64-4-570 4657