Atal to Zojila: Mastering India’s Landmark Tunnel Projects for UPSC
Q. With reference to tunnel infrastructure in India, consider the following statements:
1. The Atal Tunnel is officially recognized as the world's longest highway tunnel above 10,000 feet.
2. The New Austrian Tunnelling Method (NATM) is primarily used for underwater metro projects in soft soil.
3. Tunnel T50 is part of the Udhampur–Srinagar–Baramulla Rail Link (USBRL) project.
Which of the statements given above are correct?
(a) 1 and 2 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3
Context
India is witnessing a significant "tunnelling boom," driven by the expansion of national highways, strategic border infrastructure, and urban metro networks. These projects represent more than just construction; they reflect the nation's determination to overcome geographical barriers and ensure all-weather connectivity to remote regions like Ladakh and Arunachal Pradesh.
Why Tunnel Infrastructure Matters
Tunnels offer smarter, safer, and more sustainable alternatives to traditional surface routes, especially in fragile terrains.
- Regional Development: Connects isolated communities to markets and essential services.
- National Security: Strengthens the strategic reach of the Armed Forces in border areas.
- Economic Growth: Reduces travel time and logistics costs by bypassing long mountain passes.
- Sustainability: Offers a lower environmental footprint compared to cutting extensive surface roads in sensitive geologies.
Key Technologies Driving the Revolution
Modern Indian tunnels have transitioned from traditional drill-and-blast methods to sophisticated, safety-integrated corridors.
- Tunnel Boring Machines (TBMs): Used for precision in metro networks and undersea sections (e.g., Kolkata and Mumbai-Ahmedabad High-Speed Rail).
- New Austrian Tunnelling Method (NATM): Widely used in the Himalayas, it allows for real-time adaptation of excavation support based on rock conditions.
- Integrated Tunnel Control Systems (ITCS): Centralized digital platforms managing ventilation, fire detection, and emergency communications.
Landmark Operational Tunnels
| Tunnel | Length | Key Features |
|---|---|---|
| Atal Tunnel | 9.02 km | World's longest highway tunnel above 10,000 feet; connects Manali to Lahaul-Spiti. |
| Dr Syama Prasad Mookerjee Tunnel | 9 km | Formerly Chenani-Nashri; twin-tube tunnel in J&K bypassing 41 km of road length. |
| Banihal–Qazigund Road Tunnel | 8.45 km | Twin-tube tunnel connecting Jammu and Kashmir; reduced distance by 16 km. |
| Sela Tunnel | - | Located at 13,000 feet on the Tezpur-Tawang route; key for Arunachal border connectivity. |
| Tunnel T50 | 12.77 km | Longest transportation tunnel under the USBRL rail project in J&K. |
| Kolkata Underwater Metro | - | India's first underwater metro tunnel beneath the Hooghly River. |
Upcoming Mega-Projects
1. Zojila Tunnel (2028): Set to become Asia’s longest bi-directional road tunnel (over 30 km project area) at 11,578 feet, providing all-weather access to Ladakh.
2. Mumbai-Ahmedabad High-Speed Rail Tunnel: Features a 4.8-km undersea section, a first for India’s defines bullet-train route.
3. Rishikesh-Karnaprayag Rail Tunnels: Spanning 125 km in Uttarakhand, predominantly tunnel-based (105 km cumulative length) to protect the Himalayan ecology.
Significance for India
- All-Weather Lifeline: Prevents the seasonal isolation of J&K and Ladakh during winter snowfall and avalanches.
- Engineering Prowess: Demonstrates India’s capability to build in extreme temperatures (ranging from -25°C to 45°C inside Atal Tunnel).
- Logistics Efficiency: The Sonamarg paired with Zojila will increase speeds from 30 km/hr to 70 km/hr.
- Employment: Projects like the Dr Syama Prasad Mookerjee tunnel drew 94% of its workforce from local J&K regions.
🎯 Analysis & Insights
Prelims mastery
Correct Answer: (c) 1 and 3 only.
Reasoning: Statement 1 is correct (recognized by World Book of Records UK). Statement 2 is incorrect because TBMs are typically used for soft soil/underwater, while NATM is preferred for challenging rock formations in the Himalayas. Statement 3 is correct.
Mains perspective
"Tunnels are the strategic arteries of India’s integrated infrastructure vision." Discuss how modern tunnelling technology is addressing the dual challenges of national security and environmental sustainability in the Himalayan region. (150 words)