Aluvionales Works in Quebradas de Iquique and Alto Hospicio, Tarapacá Region

Description: The Ministry of Public Works (MOP), through the Directorate of Hydraulic Works (DOH), develops the construction project of 6 alluvial walls with their respective discharge dump, in the following streams: Santa Rosa, Zofri, Seca Baja and Alta, Esmeralda, Pampa El Molle. These projected works seek to retain the total detrital volume generated by this type of meteorological phenomena through the construction of a wall dam with heights that vary between 6 and 9 meters approximately. Additionally, Quebrada Pampa El Molle plans the construction of a retention pool whose storage will be 243,043 m3, and a linner tunnel that passes under the railway line. These retention and evacuation works will attenuate the peak flow, its speed and drag capacity, in such a way to retain all the alluvial material that goes down the ravine ensuring that the excess outflow is gradually evacuated towards the same ravine, continuing its natural course. For the construction of these works, the use of existing roads is considered in: Quebrada Seca Baja and Pampa El Molle; along with the qualification of four (4) sections of basic road of lengths between 130 and 560 m in Quebradas Santa Rosa, Zofri, Seca Alta and Esmeralda. Objective The works of alluvial control and liquid floods, have like objective to avoid the destructive effect that can generate an alluvial event, retaining a volume of maximum flow through the use of works of catchment, retention and evacuation, allowing to attenuate the peak flow, its speed and capacity of drag, in such a way that the excess salient flow is evacuated gradually towards the same stream, continuing its natural course. The design of projected walls considers the support of a flood with return period of 100 (T = 100) years plus rematch.