Evaluation of Vulnerable Zones in Puerto Vallarta due to a Local Tsunami

Abstract:

Based in the high possibility of occurrence of a tsunamigenic earthquake of magnitude 8.0Mw offshore from the northern coast of Jalisco and Bahía de Banderas, Mexico. The vulnerability of Puerto Vallarta to a direct flood hazard associated to the tsunami is evaluated. Assuming a simplified model of the seismic source a numerical method is used to calculate the tsunami run-up and the extent of flooding in Puerto Vallarta area. Floods heights and arrival times in the first ten hours after the earthquake and flood boundaries in different watersheds were estimated. This method was previously testing, modeling the October 9, 1995, Jalisco Earthquake and Tsunami, the results obtained were similar to the field observations and testimonies performed in 20 sites along 100 km on the coast of Jalisco, related to the height and flood extension reached during the tsunami. To estimate the vulnerability the following variables were considered: distribution of population density, population by age or physical limitation, housing characteristics, level of education, cost of goods in the affected area, location of key facilities, cost of cleaning the affected area, and change of land use policy in the Puerto Vallarta area. The study indicates that the vulnerability is very high in the Salado basin, and high in the Pitillal and Mascota-Ameca basins.