espanolEsta investigacion se oriento a analizar la vulnerabilidad al riesgo de inundacion en la cuenca baja del rio Gaira (Santa Marta), la cual se dividio territorialmente en tres sectores, permitiendo realizar comparaciones intra e intersectorial. Asi mismo, determinar el sector que presento el mayor nivel de riesgo ante cualquier tipo de inundaciones. Para medir la vulnerabilidad global se adopto la metodologia establecida por Wilches-Chaux (1989) y los trabajos desarrollados por Caceres (2001), Gomez (2003), Parra (2003), Reyes (2003) y Jimenez (2005) sobre el tema de vulnerabilidad en cuencas hidrograficas. Segun los resultados, se observo que la cuenca baja del rio Gaira ciclicamente sufrio en los ultimos cinco anos inundaciones, producto de acciones antropicas. Las recientes construcciones civiles en areas inadecuadas, la deficiente planificacion urbana, el desconocimiento de planes de emergencia y la debil capacitacion de la poblacion, son factores que incidieron en la alta vulnerabilidad de la cuenca baja, la cual alcanzo un 69.5% y un valor promedio de 2.78. Las vulnerabilidades tecnica y educativa presento valores promedios de 3.37 y 3.23 y valoraciones de 84.26% y 80.90%, teniendo una vulnerabilidad Muy Alta. Asimismo, las vulnerabilidades ideologica y social obtuvieron promedios de 1.75 y 1.98 y valoraciones de 43.73% y 49.48%, alcanzando un indice de caracterizacion Medio. EnglishThis research was aimed at analyzing the vulnerability to the risk of flooding in the lower river basin Gaira (Santa Marta), which is divided geographically into three sectors, allowing comparisons within and between sectors. Also, determine the sector with the highest level of risk from any type of flooding. To measure the overall vulnerability adopted the methodology established by Wilches-Chaux (1989) and the work done by Caceres (2001), Gomez (2003), Parra (2003), Reyes (2003) and Jimenez (2005) on the subject of vulnerable watersheds. According to the results, we observed that the lower river basin suffered Gaira cyclically over the past five years flood, the result of human actions. Recent civilian buildings in inappropriate areas, poor urban planning, lack of emergency plans and poor training of the population, are factors that affected the vulnerability of the lower basin, which reached 69.5% and an average value of 2.78. Education and technical vulnerabilities presented average values of 3.37 and 3.23 and 84.26% and valuations 80.90%, with a very high vulnerability. Likewise, ideological and social vulnerabilities were averages of 1.75 and 1.98 and 43.73% and valuations 49.48% to an index of Middle characterization.