The rains and landslides registered in Petrópolis since Tuesday, 15, resulted in at least 171 deaths in the city. With searches for the missing still in progress, the situation is equal to the most tragic in the history of the municipality of Serra in 1988 when the city also recorded 171 deaths according to data from the municipal Civil Defense.
In this century, the greatest tragedy had occurred in 2011, with 71 dead in Petrópolis and more than 900 in the Serra (mostly in Nova 428 dead, and Teresópolis, 387) according to the Brazilian Atlas of Natural Disasters.
According to the Contingency Plan of the municipality of Petrópolis for heavy rains Summer 2021/2022 prepared by the municipal Civil Defense there are reports of floods in the city since 1850, but the cases became more serious in the following century especially with the advance from urbanization to hillside areas.
“The geological characteristics, the urbanization process and land occupation, in addition to the physical and natural changes in the regions of the five districts, reinforce the condition susceptible to mass movements, especially when there is an increase in rainfall”, he points out.
“Petrópolis, in the last decades, has been suffering an intense urban expansion, without adequate planning of the use of the land. population and the existing social condition, is a reality that increases the degree of risk in relation to the events of gravitational mass movements, floods and inundations.”
The relief is also a factor related to heavy rains in the city. “The relief of Petrópolis acts as an important factor in the increase of air turbulence, mainly in the passage of cold fronts and lines of instability where the air rises and loses temperature, causing heavy and prolonged rains. The geographical position of proximity to the tropics allows strong solar radiation, and the proximity to the ocean surface, increasing the evaporation process, which favors the formation of clouds that will precipitate over the region”, highlights the plan.
The city is located in a mountain range, at an average altitude of 840 meters. The estimated total population is 307.1 thousand inhabitants, according to the IBGE. Almost 20% of the territory of Petrópolis covers areas evaluated as high and very high risk for landslides, floods and floods, according to the Municipal Risk Reduction Plan, released in 2017 by the city hall. According to the study, the city has 27,704 homes in high and very high risk locations.