Larsen & Toubro (L&T) has broken a world record on the 125 kilometre Rishikesh Karnaprayag Broad Gauge Rail Link in Uttarakhand. On 29 June, its single shield hard rock tunnel boring machine (TBM) ‘Shiv’ advanced 790 metres in just 31 days, a feat achieved one day ahead of the baseline schedule.

‘Shiv’ completed the 10.29 kilometre downline tunnel between Devprayag and Janasu, running parallel to the 10.47 kilometre upline tunnel finished by sister TBM ‘Shakti’ on 16 April 2025. Together, the twin tubes form India’s longest transportation tunnels. Their combined excavation—totalling 30 kilometres including escape passages and niches—was 70 per cent TBM driven, with the remainder executed by drill and blast under the New Australian Tunnelling Method.

Average monthly progress reached over 400 metres with TBMs and more than 70 metres with drill and blast. L&T credits meticulous logistics, resource mobilisation and support from Rail Vikas Nigam Ltd for completing excavation ahead of schedule despite challenging geology, high water ingress, heat and humidity.