Informing the development of tsunami vertical evacuation strategies in New Zealand : a thesis presented in fulfilment of the requirements for the degree of Doctor of Philosophy in Emergency Management at Massey University, Wellington, New Zealand

Tsunami education and evacuation planning promote evacuation to high ground in the event of tsunami. In some low-lying coastal areas, the distance to safety on high ground or inland of the hazard zone may exceed the travel distance possible in the time before wave arrival. This is a particular problem in local-source tsunami with arrival times of less than one hour. Vertical evacuation provides alternative refuge within the inundation zone. Buildings, towers or berms can provide refuge at elevations above the tsunami flow depth, but must be designed to be effective in the maximum credible tsunami. The potential benefits and costs of vertical evacuation buildings were demonstrated during the 2011 Great East Japan earthquake and tsunami, when thousands of people took refuge in such structures. The aim of this thesis is to enhance the current theoretical and methodological basis for development of vertical evacuation strategies in New Zealand. To achieve this aim, numerical simulation of local-source tsunami is conducted at Napier, Hawke’s Bay, New Zealand, to establish the maximum credible inundation extent, flow depth and arrival times. Interview data describe the use of vertical evacuation in the 2011 Great East Japan tsunami, and surveys are used to investigate intended evacuation behaviour in a local-source tsunami. Finally, an existing geo-spatial evacuation analysis method, augmented with temporally-variable exposure and distributed travel speeds, is used to assess pedestrian evacuation potential in local-source tsunami. The method is demonstrated in an assessment of the need for vertical evacuation in Napier. The outputs of the four stages of research enhance the theoretical basis for planning evacuations in local-source tsunami, extends Geographic Information System-based evacuation modelling methods, and provides empirical advances in tsunami hazard and evacuation planning at Napier. The proposed methodology is applicable to other locations, thus contributes to tsunami risk reduction in New Zealand and internationally.
Tsunamis, Emergency management, Evacuation, New Zealand, Research Subject Categories::SOCIAL SCIENCES::Business and economics