Abstract. The so-called "El Trébol" is a critical road interchange in Quito connecting the north and south regions of the city. In addition, it connects Quito with the highly populated "Los Chillos" valley, one of the most traveled zones in the Ecuadorian capital. El Trébol was constructed in the late sixties in order to resolve the traffic jams of the capital city and for that purpose the Machángara river was rerouted through a concrete box tunnel. In March 2008, the tunnel contained a high amount of trash furniture that had been impacting the top portion of the tunnel, compromising the structural integrity. On the 31st of March 2008 after a heavy rainfall a sinkhole of great proportions was formed in the Trébol traffic hub. In the first few minutes, with an initial diameter of 30 meters. The collapse continued to grow in the following days until the final dimensions of 120 meters in diameter and some 40 meters of depth, revealing the Machángara river at the base of the sinkhole. A state of emergency was declared, the cause of the sinkhole was a result of the lack of monitoring of the older subterranean infrastructure where trash had accumulated and damaged the concrete tunnel that channelized the Machángara river until it was worn away for a length of some 20 meters, leaving behind the sinkhole and the fear of recurrence in populated areas. In an intend to understand the causes and consequences of this sinkhole event, rainfall data are shown together with hydrogeological characteristics and a view back to the recent history of sinkhole lineation or arrangement of the city of Quito. The economic impact is also emphasized, where the direct costs of the damage and the reconstruction are presented and compared to indirect costs associated with this socio-natural disaster. These analyses suggest that the costs of indirect financial damage, like time loss or delay, and subsequent higher expenses for different types of of vehicles, are equivalent to many times the costs of the reconstruction of El Trébol.