Registros de desastres naturais e sua relação com a dinâmica de ocupação urbana em Salvador, Bahia (Brasil).

Abstract

Salvador stands out in the national context as the Brazilian city with the highest number of landslide occurrences, a phenomenon whose causes are not solely attributed to natural factors but are, above all, deeply rooted in social vulnerability. Among these natural disasters, cities also experience frequent flooding events. Within this context, it is essential to understand how such socio-environmental disasters have influenced, and been influenced by, historical patterns of urban occupation, particularly in the Camarajipe River Basin. Understanding the interactions between urban occupation, public intervention, and the occurrence of landslides and floods is crucial for revealing the social and environmental consequences of these processes on the most vulnerable populations. This study aims to evaluate the relationship between urban development, public works, landslides, and flooding over time in the city of Salvador. This study draws on news reports, historical documents, and academic literature to trace the dynamics of urbanization, with a particular focus on the Camarajipe River Basin, the largest urban watershed in Salvador and an emblematic area owing to its urbanization history and recurrent natural disasters. We conducted a survey of historical and bibliographic data, along with a documentary analysis of news articles, to identify the locations of landslides and flooding, their repercussions, and interventions carried out by the state over time. As a result, we established a timeline highlighting the changes in occupation patterns, transformations resulting from public work, and their impact on hydrological circulation. Our analysis shows that throughout Salvador’s urban development, areas with steeper slopes and higher landslide risks were allocated to low-income populations, who were pushed toward more distant and precarious locations. This allocation privileged flatter, more central areas for socially and economically advantaged groups and the establishment of major developments and public institutions. We also observed direct interventions in the city’s river courses, such as channelization and riverbed diversions, which were executed without considering the natural dynamics of local hydrography. These actions exacerbated landslide processes in headwater areas and intensified flooding and inundation in lower flatter zones that do not function as primary circulation routes. By examining the temporal spectrum from 1551 to 2023, we demonstrate how urban development policies, often marked by neglect and inequality, have contributed to the emergence of a city characterized by deep social and territorial contrasts. Therefore, we emphasize the importance of considering urban history and land occupation policies to understand current socio-spatial conditions and to advocate for more equitable and integrated interventions aimed at minimizing the impacts of natural disasters in vulnerable areas.