Quazigund-Banihal Tunnel An Engineering Marvel

Sanjay Kumar Sinha, Founder and Managing Director, Chaitanya Projects Consultancy, gives an inside view of how Chaitanya Projects skilfully maintains the arterial Quazigund-Banihal Tunnel in J&K, and explains the technical intricacies of the project, detailing how the company ensured that every aspect of the tunnel operation will continue to be of stringent international standards, as originally designed and constructed, with respect to user safety, efficiency, and sustainability.

The Quazigund-Banihal tunnel, one of the most ambitious infrastructure projects in India, stands as an engineering marvel in the challenging terrain of Jammu & Kashmir. Stretching across 8.45 km, it plays a crucial role in reducing travel time, bypassing hazardous sections of the Jammu-Srinagar highway, and offering a safe, all-weather connection to the Kashmir Valley. It exemplifies the fusion of advanced tunneling techniques, safety protocols, and sustainable operational systems.

Behind this achievement is the expertise of Chaitanya Projects Consultancy Pvt. Ltd., which, in partnership with ISAN Corporation, was appointed as the Independent Engineer (IE) during the Operation and Maintenance (O&M) phase. Their involvement ensured that the tunnel, which is equipped with the highest standards of safety systems, will continue to operate at the designed level of road user safety, efficiency, and sustainability.

Engineering Precision: From Concept to Execution

The Quazigund-Banihal tunnel is situated in one of the most geologically complex regions in India, where constructing a tunnel in the Himalayas posed numerous challenges. To overcome these, the project employed the New Austrian Tunneling Method (NATM), a technology widely used in tunneling projects across high-stress mountainous regions. The NATM technique relies on controlled drill-and-blast excavation, which was essential for navigating through the varying rock types and pressure zones encountered during the project.

The Role of NATM

Unlike other methods, NATM is adaptable to the geological conditions encountered during excavation. It involves careful observation and measurement of the rock mass behavior, allowing engineers to adjust support systems as needed during tunneling. This approach is particularly valuable in the Himalayas, where rock conditions can change unpredictably.

Key aspects of the NATM approach:

• Real-time Monitoring: Sensors installed throughout the tunnel provided real-time data on rock pressure and deformation. This allowed for continuous adjustments to the support structures to maintain the tunnel’s stability.
• Primary and Secondary Linings: After excavation, primary linings were installed to stabilize the tunnel, followed by a more permanent secondary lining made of reinforced concrete. These layers provide long-term stability against rockfall, water seepage, and seismic activity.
• Ground Reinforcement: In some sections, rock bolts and shotcrete (sprayed concrete) were used to reinforce weak sections of rock, ensuring that the tunnel remained stable throughout the construction and operational phases.

The project took nearly a decade to complete, with major excavation breakthroughs occurring in 2018.

Advanced Safety Systems for Ensuring Year-Round Reliability

Safety is one of the foremost concerns in tunnel design and operation, and the Quazigund-Banihal tunnel is equipped with a robust network of safety systems to ensure uninterrupted operation. The focus was not just on structural safety but also on preparing for potential accidents, fires, or hazardous conditions inside the tunnel.

Fire Detection and Suppression Systems

The tunnel is equipped with a comprehensive fire safety system, which includes linear heat detection sensors that run along the tunnel's length. These sensors are designed to detect temperature spikes that could indicate a fire. In case of a fire emergency, the tunnel is divided into five fire zones, with hydrants and fire-fighting equipment located every 250 meters along both tubes. Each fire zone can be isolated, allowing emergency crews to deal with fires efficiently without shutting down the entire tunnel.

Fire-Rated Doors

Cross-passages are placed every 500 meters. These passages, equipped with fire-rated doors capable of withstanding fire for up to two hours, provide a safe escape route for tunnel users during emergencies. The doors, built to international fire safety standards, ensure that fire or smoke from one tube does not enter the other, preserving the safety of both the infrastructure and the people inside.

Automatic Incident Detection (AID) System

The tunnel uses an Automatic Incident Detection (AID) system integrated into its CCTV network. Cameras are installed at 75-meter intervals, constantly feeding video data to the control room, where operators use algorithms to detect incidents such as traffic congestion, stopped vehicles, or accidents. This real-time data enables the tunnel operators to respond swiftly to any disruptions, minimizing the risk of secondary accidents or prolonged traffic delays.

AID systems are particularly crucial in long tunnels, where visibility is often reduced, and vehicles may not be immediately aware of obstacles ahead. The AID ensures that operators can close off sections of the tunnel quickly, redirecting traffic as necessary to maintain the tunnel’s smooth operation.

Ventilation and Environmental Efficiency

One of the most technically challenging aspects of tunnel design is managing air quality, especially in longer tunnels where pollutants can accumulate rapidly. The Quazigund-Banihal tunnel is equipped with an advanced ventilation system designed to maintain air quality, even during heavy traffic or emergencies.

Dual Ventilation System

The tunnel employs both longitudinal and transverse ventilation systems. The longitudinal system relies on jet fans placed at intervals along the tunnel’s ceiling, which continuously push fresh air through the tunnel and exhaust polluted air. Meanwhile, the transverse system, consisting of multiple ventilation ducts, pulls in fresh air from one end and expels it through exhaust vents located at strategic points throughout the tunnel.

These systems are monitored by a network of pollutant sensors that detect levels of carbon monoxide (CO), nitrogen oxides (NOx), and particulate matter (PM) in real time. If pollution levels exceed safe thresholds, the ventilation system automatically adjusts fan speeds to restore air quality to acceptable levels.

SCADA-Integrated Ventilation Control

The entire ventilation network is controlled through a Supervisory Control and Data Acquisition (SCADA) system, which monitors and controls not only the ventilation but also the tunnel’s lighting, public address system, and emergency response protocols. SCADA enables remote monitoring and automated adjustments to all critical systems, ensuring that the tunnel remains operational and safe even during peak traffic or in the event of an emergency.

In addition to managing regular traffic, the SCADA system is programmed to handle emergency situations, such as fires. During a fire, the ventilation system shifts into emergency mode, directing airflow away from the fire zone and toward the nearest ventilation ducts to clear smoke quickly and provide fresh air for evacuees.

Operational Efficiency: SCADA and Emergency Response

Operational efficiency goes beyond routine traffic management. In the Quazigund-Banihal tunnel, emergency response systems are woven into the very fabric of the infrastructure. Emergency Call Stations (ECS), positioned every 250 meters, allow stranded drivers or passengers to contact the control center directly, triggering immediate responses from rescue teams.

At both portals, the tunnel is equipped with medical rooms, ambulances, and fire-fighting units stationed for rapid deployment. These facilities are supported by UPS-backed lighting systems, which ensure that critical systems remain operational even during power outages.

The combination of these safety features ensures that the Quazigund-Banihal tunnel is not only safe but also highly efficient, allowing rapid response to any issue that could disrupt its operation.

Sustainability and Environmental Impact

Sustainability was a major consideration throughout the design and operational phases of the Quazigund-Banihal tunnel. Given the sensitive environmental context in the Himalayan region, the project integrated multiple eco-friendly features.

Drainage and Water Management

The tunnel's drainage system was designed to handle both groundwater and surface water effectively, minimizing the risk of seepage or flooding. Waterproof linings were installed to prevent water infiltration, protecting the tunnel structure and reducing maintenance needs over the long term.

Energy-Efficient Systems

To reduce the tunnel's carbon footprint, energy-efficient LED lighting and low-power ventilation fans were installed. These systems are powered, in part, by solar panels placed at the tunnel’s service buildings, contributing to the project’s goal of minimizing energy consumption. Additionally, by shortening travel distances, the tunnel contributes to a significant reduction in vehicle emissions, further enhancing its environmental benefits.

Engineering Excellence and a Lasting Legacy

The Quazigund-Banihal tunnel is more than just a transportation project; it is a beacon of modern engineering, where safety, sustainability, and operational efficiency meet. Chaitanya Projects Consultancy, acting as the Independent Engineer, ensured that every aspect of this project shall continue to adhere to the highest standards of technical excellence as it was originally designed and constructed.

Their expertise in monitoring and maintaining the tunnel’s structural integrity, optimizing operational efficiency through SCADA, and implementing advanced safety systems has cemented the Quazigund-Banihal tunnel’s role as a vital link for the region’s future growth and sustainability. As travel through the treacherous Himalayas becomes safer and more efficient, the tunnel stands as a testament to how cutting-edge engineering can transform landscapes.