La Josefina Landslide Dam and Its Catastrophic Breaching in the Andean Region of Ecuador

Abstract

Abstract On March 29, 1993, a large landslide (20 million m3) took place northeast of Cuenca city in Ecuador, damming the Paute river. During the next 33 days, an artificial lake upstream of the blockage (200 million m3) was formed, flooding fertile land and destroying houses, roads, railways and a regional thermoelectric plant. On April 23, the water began to overflow out of the dam through a channel which was excavated in order to reduce the water volume accumulated in the lake and avoid catastrophic damages downstream. On May 1, the breaching of the dam produced a peak discharge of 10,000 m3/s, destroying roads, house, bridges, etc., downstream. This work describes the rupture of the dam and the routing of the flood wave. Models used to predict the rupture time and peak discharge of the flood are also compared. In addition, some aspects of the crisis management are presented.