A GIS-Based System for Spatial-Temporal Availability Evaluation of the Open Spaces Used as Emergency Shelters: The Case of Victoria, British Columbia, Canada

Abstract

Canadian emergency management planners have historically ignored the self-motivated evacuation procedures of people who cannot initially choose the safest evacuation areas. In densely developed urban areas, open spaces can be seen as ideal evacuation areas and should thus be included in shelter planning. In this study, the public open spaces in Great Victoria were selected as the study area and evaluated using GIS technologies. A multi-criteria TOPSIS evaluation model was used to conduct comprehensive quantitative evaluations of the open spaces’ safety, accessibility, and availability. Through hybrid process, service area, and POI aggregation coupling analyses, a model is created that provides an overall evaluation at the district level. In addition to providing a model for evaluating open spaces as emergency shelters, applicable to most Canadian cities, this study emphasizes the importance and disadvantages of open space emergency shelters in Canada, which have heretofore been ignored by decision makers. In Great Victoria, we found that the distribution of open spaces does not match the dynamics of the population distribution, meaning that through inadequate preparation some districts lack a safe evacuation place—this in an area where people are at high risk of earthquake disasters and their subsequent effects.

Factors Influencing the Intrinsic Seismic Risk of Open Spaces in Existing Built Environments: A Systematic Review

“…Moreover, it is also possible to use the overall OS length to compare different urban areas, using the street network density index, defined as the ratio between the total length of streets within a sector and the sector's overall area [55]. Lastly, the OS's area has a particular role in estimating the ability of ASs (e.g., squares, parking) to be used as secure spaces [29,61]. The "temporary secure OSs" index expresses the ratio between the total area of secure OSs and the number of evacuees [12].…”

“…The accessibility for vehicles/pedestrians describes the exclusive use or not of the OS, which notably affects the type and speed of evacuation flow after a disastrous event [42,59] or the possibility of being reached by emergency services [61]. Different types of flows along the same LS during the evacuation phase have an impact on the risk for pedestrians, especially considering the different mental state of the drivers compared to ordinary days [57,62] or the possibility of having multi-directional movements in the same OS, especially in the ASs [29].…”

“…It is possible to find many approaches in the literature to estimate in advance the expected evacuees' density. Some of them consider a static amount of people, including only the residents in the count [12,48,52]; others add at least the employees of business activities and/or the tourist flow facing the OS considered [40,49,60,63]; finally, more indepth studies consider the concentration variation along different times of the day (e.g., the daily movement of the users) [9,23], the week (e.g., weekday, weekend) [23,61], or the year (e.g., seasonal use of property, touristic flows) [59]. The density could be approximated on a semi-quantitative basis [29], using a demographic database [46] or by comparing the ordinary situation with the evacuation demand [56].…”

“…The seismicity is among the pivotal factors that influence the seismic local vulnerability of the BE and the OSs [38,45,53], primarily important for a complete evaluation of the vulnerability of LSs identified as evacuation paths [9] or ASs as safe areas [61]. A seismic hazard could be evaluated qualitatively by adopting the values of the seismic zonation, if available, or quantitatively using the peak ground acceleration [22][23][24]29,40,43,48,63].…”

Efficient Crisis Management by Selection and Analysis of Relief Centers in Disaster Integrating GIS and Multicriteria Decision Methods: A Case Study of Tehran

“…Su et al [14] developed a two-stage floating catchment (2SFCA) method with variable service radius, and evacuation radius has been developed to describe emergency shelter access in the main Lanzhou area and compare it with traditional 2SFCA. Yao et al [15] used a multicriteria TOPSIS evaluation model and, through a combined process, service area, and POI analysis, developed a model that provided an overall assessment at the district level. e results showed that the distribution of open spaces did not match the dynamics of population distribution.…”