Escape routes and safe points in natural hazards. A case study for soil

Abstract

The scope of this work was to develop soil liquefaction and landslide hazard maps, by computing Peak Ground Acceleration (PGA) for a return period of 475 years, to outline safe points and escape routes designed for schools situated in the drainage basin of Xerias River at northeastern Peloponnese, Greece. The school locations were spatially correlated with each geohazard map to assess the potential hazards to schools within the study area. Web maps illustrating safe and unsafe areas for both geohazards were developed though the GIS online platform for the town of Corinth and four settlements of the study area, where schools exist. Safe points were identified, and routes for evacuation from schools to these locations were mapped using the shortest paths on the existing road network for each geohazard. All the data was integrated into the GIS application available to the public. The findings indicated that 75% of the schools in the study area are situated in areas susceptible to soil liquefaction and landslide hazards. The northern part of the town of Corinth, which includes 62% of the town's schools, is situated in unsafe areas to soil liquefaction. Unsafe areas for landslides are located in the central and northern section of the town, encompassing 35% of the schools. The school buildings in one settlement within the study area are situated in safe areas for both geohazards. The schools in the remaining settlements are sited in areas considered unsafe due to either liquefaction or landslides hazard. A total of 12 safe points were proposed for soil liquefaction hazard and 17 for landslide hazard across all the studied urban areas. The suggested escape routes for both geohazards range from 200 to 1094 m, distances that teachers and students can easily walk. The proposed method can rapidly and effectively identify safe locations and evacuation routes, facilitating authorities in planning for evacuations.