Comprehensive Guidelines for Road Tunnel Infrastructure in India

After the 2023 Silkyara-Barkot tunnel collapse, the Ministry of Road Transport and Highways (MoRTH) issued new safety guidelines for highway tunnels.

Why the New Guidelines Were Needed

Recurring Tunnel Collapses: Multiple tunnel failures in recent years highlighted gaps in planning and execution.
Strategic Expansion: India’s push to extend highways into border areas, Himalayan terrain, and eco-sensitive zones increases geological risk.
Weak DPR Quality: Tunnel DPRs are often reduced to procedural documents rather than robust risk-management tools.
Himalayan Fragility: Highly variable geology makes predictive modelling based on limited tests unreliable.

Risk Ownership: Contracts must assign every identified project risk to the party best equipped to manage it.
Stakeholder Coordination: Planning requires early consultation with Forest, PWD, Railways, and Disaster Management departments.
DPR Mandate: Every Detailed Project Report (DPR) includes a Geotechnical Baseline Report (GBR) and a live Risk Register.
- Geotechnical Baseline Report: Contractual reference for expected ground conditions.
- Risk Register: Lists identified hazards with site-specific mitigation measures.
Portal Siting: Alignment planning must use the Landslide Susceptibility Maps by the GSI to avoid portals in unstable zones.
Rescue Pipe: High-risk collapse zones require installation of a 0.9-metre NP-4 escape pipe in the tunnel invert (floor).
Rescue Staging: One mobile rescue container for 12 workers must be placed 150-300 metres behind the tunnel face (active excavation point).
- Survival Support: Rescue containers will provide at least 24 hours of oxygen, water, and communication facilities.
Evacuation Gaps: Pedestrian cross-passages are provided at 300-metre intervals for emergency escape.
Early Oversight: Tunnels above 1.5 kilometres require intimation to the Ministry of Road Transport and Highways (MoRTH) Tunnel Zone.
Quality Assurance: An independent expert panel will review the DPR and construction methodology before execution.

Clear operational procedures for:
- NATM (New Austrian Tunnelling Method): Design-as-you-go approach; mandatory excavation and support sheet (RESS) for each round.
- TBM (Tunnel Boring Machine): Enhanced safety protocols for roof collapse and water ingress.
Tunnels to be classified into collapse-risk zones, even after primary support installation.

Emergency Response Plan (ERP): Prepared in advance for all identified risk scenarios. Updated weekly based on site progress.
First Responders: Mandatory training for Shift Managers as first responders to initiate rescue and safety protocols.
Clear Command Structure: Defined roles for District Magistrate (Incident Commander), project agencies, local administration, NDRF/SDRF, and Armed Forces.
Operational Reality Check: Acknowledges that disaster-response forces need technical support to operate safely inside tunnels.

Completed Works: 42 road tunnels covering 60.37 km have been completed across 27 National Highway (NH) projects.
Ongoing Projects: 57 tunnels spanning 93.96 km are under construction across 37 NH projects.
Network Target: India aims to develop an aggregate road tunnel network of 331 km by 2026-27.
Construction Methods: Over 80% of Himalayan tunnels use NATM (New Austrian Tunnelling Method), while urban coastal projects rely mainly on TBMs (Tunnel Boring Machines).

Dr. Syama Prasad Mookerjee Tunnel: India’s longest operational road tunnel (9.28 km) on NH-44 between Chenani and Nashri in Jammu and Kashmir.
Atal Tunnel: World’s longest (9.02 km) highway tunnel above 10,000 ft beneath Rohtang Pass at the Eastern Pir Panjal range in Himachal Pradesh.
Sela Tunnel: World’s longest (2.5 km) twin-lane tunnel above 13,000 ft, connecting Tezpur in Assam with Tawang in Arunachal Pradesh below Sela Pass.

Zojila Tunnel: Asia’s longest (13.1 km) bi-directional road tunnel will connect Sonamarg in Jammu and Kashmir with Drass in Ladakh.
Shinku La Tunnel: World’s highest tunnel (4.1 km) at 15,800 ft between Lahaul in Himachal Pradesh and Zanskar in Ladakh.
Brahmaputra Underwater Tunnel: India’s first proposed road-cum-rail underwater tunnel, 32 m below the Brahmaputra riverbed in Assam.