Huayco is an old Quechua word meaning depth, or valley. A huayco is a typical Andean landslide and avalanche of rocks, earth, mud, water and sometimes snow. It is triggered by a heavy rain or a catastrophic flash flood. Ancient local superstitions believe that huaycos happen when the apus and mukis - the spirits of the mountains - are angry.
Huaycos are frequent during the rainy season (December – March). On the Central Andino railroad, Rio Blanco is particularly exposed. The line is often blocked during the night. It can happen weekly, or even several times per week. Protecting this well-know dangerous area with strong concrete walls is the responsibility of the Peruvian government, which does nothing. Local people endure the burden of destruction and sometimes death. The railroad bears the cleanup and repairing costs.
The picture shows the main line at Rio Blanco where it is affected by frequent huaycos, just after one such event has happened during the night and railroaders have worked expeditiously to remove the mud. This is another reason why the Lima – Oroya line (the Central Andino) is considered the most difficult railroad in the world.