India’s central government is taking serious action after recent cloudbursts and floods wreaked havoc on highways in Himachal Pradesh and Uttarakhand. A top official from the Road Transport and Highways Ministry announced that new guidelines are on the way, specifically focusing on ‘slope stabilization’ to prevent future road collapses in these vulnerable, disaster-prone regions.
V. Umashankar, Secretary of the Road Transport and Highways Ministry, confirmed that these upcoming guidelines will make slope stabilization a mandatory pre-construction requirement for all new roads in hilly areas. This is a significant shift from current practices where such measures are often considered after construction. Furthermore, all future project contracts with concessionaires will be updated to include these crucial new requirements.
The decision comes after a close examination of recent road failures, including 15 damaged sections on the vital National Highway-21 (Kiratpur-Manali Highway). Interestingly, areas where slope stabilization techniques had already been implemented proved resilient, holding up against the destructive force of cloudbursts and floods.
Slope stabilization is an essential engineering practice designed to fortify unstable terrain, preventing landslides and erosion. It encompasses a range of techniques aimed at boosting a slope’s safety by controlling soil and rock movement, effectively managing water runoff, and strengthening the ground structure. Common approaches include building retaining walls, installing soil nails and anchors, applying shotcrete, implementing sophisticated drainage systems, planting protective vegetation, and strategically reshaping the slope for enhanced stability.
Last July and August, severe cloudbursts and relentless heavy rainfall across Himachal Pradesh caused widespread road collapses and devastating landslides. This catastrophic weather event led to the closure of National Highway-21 for days, completely severing a critical connection between Punjab and Leh. The National Highways Authority of India (NHAI) reported that ten sections of this highway were entirely swept away, with five more sustaining partial damage. In response, NHAI allocated ₹100 crores for immediate repairs and announced plans to explore comprehensive solutions for the highway’s long-term restoration.
Similarly, in early August, flash floods in Uttarakhand’s Uttarkashi district severely impacted National Highway-34. This crucial route, which follows the Ganga River through the district, suffered significant damage, disrupting the sacred pilgrimage path to Gangotri.
The official highlighted that most of the damage to national highways occurred in segments built alongside riverbanks. This vulnerability was intensified by rising river levels, a problem compounded by various factors, including increased human habitation along these waterways.
He further clarified that the structural failures were primarily seen on the ‘valley side’ – the part of the road that descends steeply towards the river winding through the valley below.
Comparable incidents of widespread damage were also recorded in Sikkim in 2023, following a Glacial Lake Outburst Flood (GLOF). This powerful flash flood, which roared downstream and decimated the Teesta III Dam at Chungthang, caused the Teesta river to swell dramatically. The surge of water obliterated roads, bridges, and vital infrastructure, including large portions of National Highway-10.
An anonymous NHAI official revealed that since 2024, 89 specific locations on the Kiratpur-Manali Highway were marked for essential slope stabilization work. While 45% of these critical interventions have been completed, it was noted that for nearly 40 of the 89 sites, stabilization efforts were undertaken after the road construction, highlighting a reactive rather than proactive approach in some instances.