Identifying the Areas at Risk of Huaico Occurrences in the Department of Lima, Peru

Because of local climate, a phenomenon called huaico occurs in the coastal regions of Peru, configured by an alluvial flow of surface runoff caused by precipitation and accompanied by the transport of solid particles. A total of 24% of the huaicos recorded in Peru from 2003 to 2019 were concentrated in the Department of Lima alone and affected 38,000 people. Thus, the aim of this study was to use Maxent to identify the areas at risk of huaicos in this department. To this end, a georeferenced database was created that included the locations of these events for modeling. We used variables suggested by Peru’s Geological, Mining, and Metallurgical Institute (INGEMMET)—geology, geomorphology, DEM, slope, and precipitation—which returned extremely high kappa coefficients. Approximately 42% of Lima’s area is likely to have a huaico occurrence. The most crucial variable for the models was the geomorphological classification characterized by the accumulation of mobilized material, as was the case in previous huaico models. In addition, the monthly approach should have been more effective at determining the differences in the precipitation levels. Thus, new models for the coastal departments of Peru using Maxent algorithms should take a new approach related to precipitation, although the use of Maxent proved satisfactory.