The role of Architecture in tsunami-risk management. Proposal for a vertical evacuation system in Viña del Mar, Chile.

The urban built environment offers a fundamental mean to reduce the risk posed by natural hazards, thereby preventing natural disasters. Disciplines like Architecture and Urban Planning become effective instruments to reinforce disaster risk governance and foster resilience. The following thesis investigates the relationship between natural disasters and built environment, focusing on the earthquake and tsunami hazard that threaten the Chilean coastal cities. It explores the coastal management strategies and the main existing mitigation systems for shore protection, both natural and engineered. Focusing on a case study, the city of Viña del Mar, it analyzes the reasons that led to the urban densification of the waterfront and the consequent risks that come from its exposure to inundation and tsunami hazard. The proposition for a tsunami vertical evacuation system in the Población Vergara has the objective of combining an effective tsunami mitigation strategy with the urban environment demonstrating the role of architecture inside the disaster management cycle. The design process, developed in three phases, consists in the draft of an assessment model for potential Tsunami Vertical Evacuation Building’s sites, the design of a vertical evacuation system composed of 22 tsunami shelters and finally the drawing of the new evacuation plan resulting from the implementation of the existing horizontal one with the new vertical evacuation system which will guarantee the rapid evacuation of all the sectors at risk.