Estudio de amenazas de origen natural en la cuenca del río ila que afectan la zona ribereña en el casco urbano del municipio de la vega para generar estrategias enfocadas en la gestión del riesgo

Abstract

The analysis of natural hazards in the Ila River basin established that the urban area of the municipality of La Vega, Cundinamarca, is highly susceptible to flash floods, inundations, and landslides, as evidenced by the increased frequency and severity of these events. In this context, Vera Rodríguez and Albarracín Calderón (2017) define a hazard as a set of external and internal processes, of natural, anthropogenic, or socio-natural origin, capable of generating significant transformations in a system, either slowly or suddenly, and with the potential to cause damage to the population, ecosystems, and their livelihoods. Based on the analysis of secondary information, fieldwork, surveys, and community mapping exercises, it was determined that the main hazard affecting the urban area is the occurrence of flash floods associated with the hydraulic dynamics of the Ila River. These torrential floods have generated processes of undermining, sheet erosion, slope destabilization, sediment transport and deposition, and flooding in the riparian zone. Critical zones were also identified, conditioned by the steep topography, the climatic regime, and the presence of poorly consolidated sedimentary materials, in accordance with the findings of IDEAM and the Colombian Geological Survey. It was further established that the presence of geological structures such as the Supatá thrust fault and the Roble fault favors the occurrence of mass movements that influence fluvial dynamics, while the location of the urban area on alluvial deposits with a low degree of confinement increases its vulnerability to torrential events. These results confirm that the geological, geomorphological and hydrological conditions of the area create a significant threat scenario, given the level of exposure to the vulnerability of the municipality's urban development, where flash floods represent the main risk factor for the urban area and constitute a fundamental input for territorial planning and risk management in the municipality.