Tsunami Vertical Evacuation Buildings - Lessons for International Preparedness Following the 2011 Great East Japan Tsunami

Abstract

Tsunami vertical evacuation is an important strategy for enhancing disaster preparedness because it provides an alternative to evacuation inland or to high ground in areas at risk of local tsunami. A large number of tsunami vertical evacuation buildings provided safe refuge in the inundation zone during and immediately after the Great East Japan tsunami on March 11th2011. This paper discusses observations of such buildings in connection with themes that arose during semi-structured interviews with local disaster prevention and emergency services officials in Iwate and Miyagi Prefectures in October 2011. The implementation of key factors in the development of tsunami vertical evacuation strategies are assessed with reference to previously published guidelines, enabling lessons to be applied in the current and future development of such strategies internationally. The most important factors for designating tsunami vertical evacuation buildings are that they be reinforced concrete construction with sufficient height in relation to inundation depth. Also important to the success of such vertical evacuation strategies are community engagement, building owner agreement, consistent and clear signage, 24-hour access and evacuee welfare.