Mantaro Hydroelectric Project

Name of Project:
Mantaro Hydroelectric Project


Corporación de Energía Eléctrica del Mantaro, Lima, Peru

Construction period:
1966 – 1973; 1979 – 1985

The hypothesis of the hydroelectric exploitation of the Mantaro River began to take shape in 1961, with the constitution of a specific state company, the Corporación Eléctrica del Mantaro (Corman).

In 1963, the contract tendered by Corman was won by a company whose lead contractor was Impregilo, the GIE Impregilo Mantaro Group.

The best possible location for the dam was 2,700 meters above sea level. The fact that the work had to be done in a remote area of the Andean plateau meant overcoming some highly complex logistical difficulties: the main building site (Kichuas) was some 400 km away, and could only be reached via inaccessible mountain roads. In order to reach the furthest building sites, a modern road network had to be built, in some cases overcoming mountain passes at over 4,000 meters in altitude.

The dam’s technical features (the hydroelectric power station was the country’s largest until 2012) involved some major challenges: the headrace tunnel (almost 20 km) was excavated in very difficult geological conditions, and particular techniques had to be used to control the high velocity of the water during river diversion.

In 1979, Electroperu assigned construction of the hydroelectric power station of “Restitución” to GIE Impregilo Mantaro Group. Inaugurated in 1984, the new power station added 216 MW power to the original plant, reaching a total of 1,008 MW.

Crest length: 200 m
Dam height: 82 m