In response to the increasing frequency of floods and landslides causing significant damage to highways, particularly in vulnerable hilly regions, the government has announced stricter guidelines for highway project preparation. These enhanced norms aim to build more resilient infrastructure that can withstand the impact of natural disasters.
A key component of the new regulations is the mandatory integration of detailed analysis based on datasets from the National Database for Emergency Management (NDEM) in all highway project reports. NDEM, developed and maintained by the National Remote Sensing Centre (NRSC) and the Indian Space Research Organisation (ISRO), serves as a comprehensive geospatial platform for disaster management, risk assessment, and infrastructure planning. The portal hosts multi-temporal satellite data, thematic layers, and decision support tools for monitoring natural hazards including floods, landslides, droughts, and cyclones.
The road transport ministry has communicated to all states and highway agencies that the dedicated analysis using NDEM datasets must incorporate the use of floodplain, digital elevation models (DEMs), and land use layers. This will help identify optimal alignments that minimize exposure to natural hazards during the alignment selection process. The analysis should integrate flood extent and river basin layers to facilitate the planning of adequate cross-drainage structures, preventing future inundation issues, as well as landslide risk mapping specifically for hill roads. The ministry has mandated that all alignment approval proposals presented before committees must clearly indicate whether NDEM analysis has been conducted and include the results for the committee's consideration.
Furthermore, when preparing project reports for highway projects in hilly areas, topographical surveys must be conducted for a 300-metre-wide strip. The base plan, created using topographical data, should be superimposed with the Indian Landslide Susceptibility Map. The landslide inventory of past incidents should be collected.
These measures follow recent incidents where sections of highways were washed away due to cloudbursts and floods in Himachal Pradesh and Uttarakhand. V. Umashankar, Secretary, Road Transport and Highways Ministry, stated that new guidelines will mandate slope stabilization prior to road construction, rather than as a post-construction measure, in hilly regions. Concessionaire agreements will also be revised to incorporate these requirements for all future projects. Slope stabilization is an engineering process that strengthens unstable slopes to prevent landslides and erosion, utilizing techniques such as retaining walls, soil nails, drainage systems, and vegetation planting.
The National Highways Authority of India (NHAI) had previously earmarked ₹100 crores for short-term rectification of damaged highways and is exploring options for permanent restoration. Damage to National Highways was predominantly observed in sections constructed along riverbanks, exacerbated by rising river levels.
