Engineering challenges for sustainable road access in the Himalayas

Improved road access is fundamental to the current drive for economic development and livelihood improvement in many parts of the Himalayas. There is a history of over one hundred years of road building in the region and an expanding road network that faces serious challenges to its sustainability. These challenges include severe terrain, dynamic geology and heavy rainfall, with earthquakes, landslides, floods, erosion and sediment posing significant hazards. In both India and Nepal there is a large body of published literature that describes the impact of these hazards on roads, and there are a number of manuals, guidelines and standards for sustainable road construction and maintenance. There is also a strong presence of geological and geohazard expertise in both countries that is able to inform decision-making in route selection and road design. However, it is apparent that this expertise is not always being used and that road construction is sometimes taking place without reference to the established manuals and guidelines. Although the guidelines themselves require consolidating and strengthening in certain areas, including a greater infusion of engineering geology, it is paramount that they are used. The future poses major challenges for the engineering sustainability of road access in the Himalayas, but these can be addressed through careful planning, thorough investigation, adherence to best practice, control of construction practices and learning the lessons of the past.