The road network between southern America’s East and West coasts is of great importancy for the urban agglomerations around Rio de la Plata, expecially because of growing export-oriented policies of Argentina. The highly mountainous terrain between Argentina and Chile makes it difficult to expand this network.

The “why” of this connection

The transit route crossing the Andes is growing in importancy. A better connection would be necessary, but the high mountainous Andean area makes it difficult to expand road network as well as the traffic ability. Problematic are the impassibility of transit routes during winter and the all season high risk potential for vehicles using the extended road sections where steep gradients and acute geological hazards exist.

Finding a way – with a feasibility study

Between Mendoza and Santiago a feasibility study for a railroad was made, which will upgrade the transit route and relieve the limited capacity of the traffic network. The principal section, which runs from Los Penitentes (Argentina) to Riecillo (Chile) including a tunnel, was investigated for its feasibility by the consortium. The main work included the investigation of geological and natural hazards in this mountainous area, the geological, geotechnical and hydrogeological mapping as well as to develop the future exploration program and compile the prognosis. Thereupon a variant study and project time-table was developed.

The water challenge

A particular challenge for the project is a hydrothermal spring issuing at Puente del Inca in Argentina. The recharge and issuing areas of the spring are to be crossed by some of the fore­seen alignment variants. The high temperature and highly mineralized spring waters are concrete aggressive and prone to producing precipitates (liming). An intensive hydrogeological and geophysical investigation program is planned in order to establish the risk potential during and on the tunnel construction.