Flood risk map from hydrological and mobility data: A case study in São Paulo (Brazil)

Abstract

Cities increasingly face flood risk primarily due to extensive changes of the natural land cover to built‐up areas with impervious surfaces. In urban areas, flood impacts come mainly from road interruption. This article proposes an urban flood risk map from hydrological and mobility data, considering the megacity of São Paulo, Brazil, as a case study. We estimate the flood susceptibility through the Height Above the Nearest Drainage algorithm; and the potential impact through the exposure and vulnerability components. We aggregate all variables into a regular grid and then classify the cells of each component into three classes: Moderate, High, and Very High. All components, except the flood susceptibility, have few cells in the Very High class. The flood susceptibility component reflects the presence of watercourses, and it has a strong influence on the location of those cells classified as Very High.

Analyzing the spatial interactions between rainfall levels and flooding prediction in São Paulo

“…All information was collected and provided by the CGE. An exploratory analysis of this data was presented in Tomás et al (2022).…”

Optimal rain gauge network to reduce rainfall impacts on urban mobility – a spatial sensitivity analysis

“…With regard to the exposure, it refers to the aggregation of items (a) and (b) in each grid cell as presented by (Tom as et al, 2022), since the damage caused by floods affects the mobility and accessibility of people living in (inhabitants) and moving through (commuters) the affected areas. Table 2 presents the coordinates of the block centroids (X,Y), the number of exposed people and the vulnerability.…”