Argentina assesses Train to the Clouds corridor 15 Mar 2018

A detailed analysis of the Tren a las Nubes, Train to the Clouds, railway in Argentina as part of the international route through the Andes to Antofagasta on the Pacific Ocean in northern Chile, has been concluded by specialist engineers from Geoconsult and Georesearch from Wals/Salzburg in Austria, to assess its need for maintenance and repair, risks to its operation and the prospects for improving the line to increase its rail operation capacity.

Fig 1. The Tren a las Nubes route between Argentina and Chile includes 21 tunnels and opened in 1949 after a construction period of 27 years

To complete the assessment, an area of approximately 10,000km² of high altitude mountainous terrain in the Andes has been subjected to a two-stage survey using modern technologies to shorten dramatically the study period and reduce the associated cost. The first stage was based on review of remote sensing data from satellite imagery and followed by workshops to identify potential risk hot spots on the rail route through the surveyed topography. In a second stage, the identified hot spot were verified and further explored by the use of drones. Together with data gathered from operation of the existing railway infrastructure on the corridor, natural hazards and specific logistical models have been developed for repair and risk mitigation construction programmes and estimates for annual additional train transport capacity through the region.

Until now the assessment of risks and associated dangers of a linear infrastructure has consisted of mapping the terrain on the ground by walking kilometre on kilometre along its entire length. In the past, the evaluation to develop models for risk analysis for the existing 570km long Salta to Socompa section of the Tren a las Nubes railway in Argentine would have taken at least six months of fieldwork. By the application of modern methods, such as the use of drones, the amount of fieldwork has been reduced to less than a month with increased data collection quality and at distinctly lower cost.

Risk analysis assessed natural hazards to the existing railway

A special challenge of the study was to investigate a vast area of about 10,000km² at a high altitude and subject to extreme climatic conditions. Acknowledging the expertise of Austrian engineers in the survey of high mountainous regions, the feasibility study for Argentina was supported by the Austrian Economic Service. After a short period, low expenditure assignment, the Geoconsult and Georesearch study team presented its risk analysis for the future of the Tren a las Nubes alignment and its potential for contributing to the economic development and improvement of living conditions in the north-western region of Argentina in Buenos Aires at the end of January.

Existing risks on the train to the clouds

The existing railway line from Salta, Argentina, to Antofagasta, Chile, was taking into operation in 1949 after a construction period of 27 years. The railway line comprises 21 tunnels, 29 bridges, 13 viaducts, two switch back bends, and 21 stations. It crosses several salt flats rises to an elevation of more than 4,400m and is in parts subject to extreme climatic conditions. The world famous tourist Tren a las Nubes train runs along a stretch of the line that includes across the famous Viaducto Polvorilla, the highest viaduct in South America.

The extensive and exposed mountain ridges of the Andes represent major challenges for planning, construction, maintenance and operation of trans-Andean traffic infrastructure. Roads are the main transport routes between Argentina and Chile, but these are often in poor states of repair and can only be used part of the year due to the climatic conditions. The study estimates the potential for increasing rail traffic along the Tren a las Nubes transport corridor as the only railway line between Argentina and Chile currently in operation. The capacity of the corridor is of major importance when considered in association with the vast natural resources in the high plateau regions of the Andes of Argentina and Chile.

Given the extreme topographical location, the extensive analysis of natural hazards on the existing rail service corridor is an important resource for decision making by the railway operator for performing adequate maintenance measures in the future. On the basis of satellite data and a first field trip and with interviews with experts, 94 risk areas have been identified and categorized by type of risk, intensity, frequency and consequence. The areas have been overflown in detail by drones to collect new field data and enable risk analysis and update. Approximately 25% of all risks have been assessed as high, and suitable technical and organisational measures have been proposed for risk mitigation.

Viaducto Polvorilla on the existing Tren a las Nubes line

The investigation of the entire railway line has shown that the railway infrastructure is safe for operation. To explore tailor-made concepts for increasing transport services on the mountainous alignment, which was designed initially for heavy traffic, the study highlights and has recommended a number of immediate repair and construction measures.

Study of the full economic and geographic conditions of the region has been assessed with the conclusion that an enormous potential of goods favourable for rail transport faces a very small actual share of railway transport mostly due to structural reasons. Logistics are highly ineffective because of missing logistic hubs, non-coordinated cycles of loading and unloading, a poor transport infrastructure with missing multimodal connections, and inadequate warehousing. Consequences are uncertainties in the reliability of rail transport, and additional costs and limitations of production capacities, which further influence unfavourably the economic development of a region.

The experts of Geoconsult and Georesearch with their partners STL-Solutions for Transport & Logistics and Planum, both from Graz, Austria, have recommended a step-by-step improvement of the existing railway line as well as establishment of multimodal hubs for goods in order to improve the economic welfare of the region.

The feasibility study has been presented end of January 2018 in the Austrian foreign economic centre in Buenos Aires to a delegation of members of the Argentine ministries for mining and infrastructure and the Argentine railways.