Flood risk management in the torrent of Los Incas in the city of Arequipa – Perú (#376)

Authors

Ccanccapa Puma, Joel

Hidalgo Valdivia, Alejandro Víctor

Noriega Aquise, Guillermo Yorel

Aguilar Chávez, Alex Eduardo

Abstract

The city of Arequipa, the second most important in Peru, faces many extreme challenges, such as high-intensity but short-in-duration rainfalls which causes floods and the swelling of the Chili River (mud and landslides). This situation exacerbates people's condition who live on the margins of the gorges and gullies; because of little or no territorial planning from public institutions. The local news evidence negligence every year in the human and infrastructural loss. The frequency of these events has increased with the time and that is the reason why rainfall thresholds have been created with their identification together with a 41- year register (1981 - 2021). For the hydrological model, the authors used the highest 24-hour precipitation data from the SENAMHI's stations (National Service of Meteorology and Hydrology of Peru) to obtain the liquid hydrograph for different return periods. Soil mechanics studies were also carried out to determine the rheological parameters of the non-Newtonian flow and then calibrate through historical events in a hydraulic model. Finally, cartographic maps were prepared to evaluate the vulnerability and high-risk areas of flooding in the Los Incas torrent.