Rohtang Highway Tunnel

The Rohtang project, awarded to a joint venture of STRABAG and Afcons in 2009, is located in the Himalaya region of northern India at an elevation of 3,000 m. The route through the approx. 9,000 m long tunnel is about 60 km shorter than the highway over the Rohtang Pass. Constructed by NATM drilling and basting, the tunnel was driven from both the south and the north portals. Before breakthrough, the north portal was only accessible six to seven months per year.
 
Geological conditions varied from good shale and migmatite to an extreme fault zone in the Seri Nalla Valley with severely fractured rock and high water pressure. A maximum overburden of 1,900 m was passed in zones of high temperatures, deformations and pressure. The most critical external influences on the works were the climatic conditions in the region.
 
Huge quantities of snow in winter, destructive avalanches in spring, followed by the monsoon season, causing landslides and floods, had a permanent influence on the works. Specially equipped and trained rescue crews, on site during wintertime and in avalanche season, more than once managed to save buried persons from death. The project was an enormous challenge for all site personnel, from management to the tunnel teams. With a trip of almost two days to reach the site from Europe, together with the remoteness of the region (even more so in the north), the elevation, and the cultural differences, many of the expats working on the Rohtang Highway Tunnel considered this to be the most extreme project they had ever worked on.