India's first eight-lane highway tunnel, constructed beneath the Mukundra Hills Tiger Reserve (MHTR) in Rajasthan's Kota district on the Delhi-Mumbai Expressway, is set to officially open for all categories of vehicles in August this year. Safety trials with light vehicles are currently underway, according to the National Highway Authority of India (NHAI).
Tunnel specifications and current status
The 4.9-km twin-tube tunnel, each tube carrying four traffic lanes, is located beneath the MHTR on the Delhi-Vadodara section of the expressway. Initially, the tunnel has been opened for cars and emergency vehicles following the completion of safety inspections. Heavy vehicles and all other traffic will be permitted only after additional evaluations regarding safety systems and mobile network connectivity inside the tunnel are completed.
Project Director Sandeep Agrawal from NHAI Kota stated in a phone interview with PTI, "The eight-lane highway tunnel on the Delhi-Mumbai Expressway beneath MHTR has not yet been officially opened for all vehicle categories. Currently, only trials are underway with light vehicles such as cars." He added that while civil work on the tunnel is nearly complete, other ongoing work inside the tunnel is being conducted alongside regular testing.
Balancing infrastructure with conservation
According to NHAI officials, the tunnel has been constructed entirely beneath the tiger reserve to avoid disturbing wildlife movement and to preserve the forest ecosystem. Its design allows animals to move freely above the tunnel without interference from highway traffic, making it an exemplary case of integrating transport infrastructure with environmental conservation. Specialised engineering techniques were used to minimise ecological impact while ensuring safe and efficient traffic flow.
The project took over four years to complete, with engineers overcoming geological and environmental challenges while adhering to stringent conservation standards. Wildlife corridors in the reserve have been maintained to ensure the uninterrupted movement of tigers and other animals.
Travel time reduction and future plans
The tunnel is expected to substantially reduce travel time on the Delhi-Vadodara stretch of the Delhi-Mumbai Expressway by eliminating nearly 25 km of winding road through the reserve. Officials anticipate that once the entire expressway is fully operational, overall travel time between Delhi and Vadodara could be reduced from approximately 20-22 hours to about 10-12 hours.
An NHAI official said the phased opening with trials will continue until all safety features, including communication systems and emergency response mechanisms, are fully validated. The tunnel will then be opened to all categories of vehicles, most likely after July 31 on any day in August this year.
The project is being seen as a landmark achievement in combining high-speed transport infrastructure with wildlife conservation, marking a significant milestone in balancing development with environmental protection.
