Browsing by Author "Guzman, Simon"

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    From urban form analysis to metrics for enhancing tsunami evacuation: Lessons from twelve Chilean cities
    (ELSEVIER, 2021) Leon, Jorge; Vicuna, Magdalena; Ogueda, Alonso; Guzman, Simon; Gubler, Alejandra; Mokrani, Cyril
    In the case of near-field tsunami emergencies, evacuation is considered the most important and effective method to save human lives. While significant efforts have been carried out to examine the relationships between urban forms and tsunami evacuation, challenges remain on delivering evidence-based urban design strategies, principles or metrics that could be applied by decision-makers to guide the physical development or retrofitting of tsunami-prone coastal communities around the world. In this paper, we propose a methodology that combines tsunami flood and evacuation modelling with statistical analysis, to examine the pedestrian evacuation potential of 67 urban samples extracted from 12 case studies in Chile. Our findings show that urban form parameters like the number of exit points out of an endangered area, the mean distance from the street network to these points, and the population density, can have a noticeable impact on tsunami evacuation times, which nonetheless is significantly dependent on the evacuees & rsquo; departure time. Moreover, we demonstrate that Chilean urban coastal development has been noticeably carried out through grid-like form patterns that might contribute to hinder evacuation in case of a tsunami emergency.
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    Urban form planning and tsunami risk vulnerability: Analysis of 12 Chilean coastal cities
    (PALGRAVE, 2022) Vicuna, Magdalena; Leon, Jorge; Guzman, Simon
    Urban form has a significant impact on risk. Spatial planning instruments can optimize urban form in areas exposed to hazards. This work discusses how urban planning instruments, specifically Communal Regulatory Plans (CRPs), affect vulnerability to the risk of tsunami inundation in Chilean coastal cities. We analyze urban form and address exposure, susceptibility, and response capacity parameters. Exposure is evaluated by comparing existing and planned densities and to what extent planned risk areas coincide with inundation zones. We analyze existing critical facilities and land uses permitted by the CRP in inundation zones to evaluate susceptibility. We explore response capacity through the street network connectivity and green areas outside the inundation zone and how CRPs influence the structuring of new roads and new green spaces. We found that CRPs do not hold the sufficient capacity to incorporate and manage the tsunami inundation risk adequately. The planning scenario leads to a systematic increase in vulnerability as cities develop in exposed areas. We suggest to strengthen CRPs capacities to prevent the construction and reconstruction of areas affected by tsunamis, reinforcing the urban fabric's potential for evacuation, and to strengthen joint work between municipal urban planning and disaster risk management departments, among other recommendations.