A Nankai megathrust earthquake is expected to result in human casualties. Therefore, especially in low-altitude areas with continuous flat terrain, it is important to promote the building of tsunami evacuation towers and specify existing buildings as shelters from tsunamis.
The purpose of this study is to analyze the efforts made by municipalities, including giving favorable treatment, such as the relaxation of floor-area ratios and the provision of subsidies for promoting the installation of tsunami evacuation buildings by private companies, as public contributions.
To achieve this purpose, four surveys were conducted in the target regions.
(1) A questionnaire on whether the target municipalities have established ordinances and systems for promoting the installation of tsunami evacuation buildings.
(2) A survey carried out by interview for analyzing the need for a subsidy system for promoting the installation of tsunami evacuation buildings, targeting the municipalities subsidizing such activities.
(3) A survey carried out by interview with a company that actually applied to the subsidy system.
(4) An analytical survey of maps, targeting the hazard maps prepared by each municipality and the maps compiled by the Geospatial Information Authority of Japan.
The four surveys elucidated the following facts.
(1) The subsidies by municipalities have yielded some results in promoting the spread of tsunami evacuation buildings.
(2) For the regions with low demand for buildings compared to cities, specific measures are required.
(3) Including the installation of tsunami evacuation buildings in the proposal standard as a development activity in urbanization-controlled areas have yielded some results in promoting the spread of such buildings.
(4) After the 2011 Tohoku earthquake and tsunami, the number of tsunami evacuation buildings increased from 39 to 215.
