The torrential flows that occurred in Venezuela in December 1999 produced the worst natural disaster in this country and maybe in Latin America. In this paper a general overview of the debris flows that took place in about 20 streams along the north central Venezuelan coast is presented. First, the major debris flow events that have occurred in Venezuela are summarized, and then the main hydrologic and sedimentologic aspects of the 1999 mudflows are discussed. The magnitude of the maximum flow discharges, and the characteristics and volumes of sediment accumulation in some basins, based on field observations, indicate that the torrential flows that took place in Venezuela were a unique event, generating hyperconcentrated flows in the morning of December 16, 1999 in most of the streams in the State of Vargas.
