The Salang Corridor crosses the Hindu Kush and is part of the Central Asia Regional Economic Cooperation Corridors (CAREC) 5 and 6. It is currently used by over 5,000 vehicles per day, which is expected to increase to 20,000 vehicles per day over the next 30 years.

The two-lane, 2.7km long tunnel that forms the core of the corridor was built in 1964. The tunnel and the surrounding road network are in very poor condition due to age, lack of maintenance, accidents, fires and conflict-related acts. The tunnel falls well short of modern safety standards and the approach roads are subject to dangerous avalanches. Steep highway grades, poor ventilation, lighting and road surfacing make travel dangerous and restrictive.


This has significant economic impact as the Salang Corridor is the main route connecting Kabul with northern Afghanistan and central Asia.


SMEC is undertaking the feasibility study and detailed engineering design to upgrade the Salang tunnel and roads. Extensive high altitude geological site investigations including mapping, drilling and laboratory testing have been a crucial part of the feasibility study.


The project is located in an extremely remote, high altitude region that in some areas is not accessible by travel. Technology including high resolution satellite imagery, GPS-enabled video camera and software are being used to help assess tunnel portal locations, road design and social impacts. Our teams are also undertaking avalanche modelling to assess sections of the highway that are vulnerable to life-threatening avalanches for average recurrence intervals of 10, 30 and 100 years.


Improving the capacity, safety and reliability of the Salang Corridor is essential to the security of Afghanistan, as the Salang Corridor is the main route connecting Kabul with its main points of supply in the north of the country and central Asia. Safe, reliable road travel through the corridor is essential to industrial development and economic growth that will improve conditions for communities in Afghanistan.


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Talk to one of our specialists about our role on the Upgrading the Salang Corridor Project.