Riesgo de tsunami y planificación resiliente de la costa chilena: La localidad de Boca Sur, San Pedro de la Paz (37° S)

Abstract

We assessed the risk of flooding due to tsunamis in the Boca Sur neighborhood, located in the Municipality of San Pedro de la Paz (37°S), Biobio region. We considered an extreme tsunami scenario generated by an earthquake of magnitude Mw 9.0. The tsunami inundation was obtained by means of the NEOWAVE model with 4 nested grids and detail topo-bathymetry data. The vulnerability analysis considered both physical, socioeconomical and organizational dimensions from statistical data given by the National Institute of Statistics (INE for its name in Spanish) at a block level as well as a field survey. Results show that the first tsunami waves would arrive 22 min post-earthquake and the maximum inundation reach up to 5 m above the mean water level with a flow depth of 2m. The risk level can be explained by several variables related to the vulnerability, namely, the prevalence of poor housing conditions, low level of social welfare, high population density and low level of community organization in case of necessary tsunami evacuation.