FCC

L&T Achieves Double Tunnel Breakthrough at Dibang

2026-05-12

Larsen & Toubro (L&T) has achieved a historic double milestone at the Dibang Multipurpose Project (Lot-02) in Arunachal Pradesh. On 28 April 2026, its Heavy Civil Infrastructure team recorded simultaneous breakthroughs in Diversion Tunnel-4 and Diversion Tunnel-5, successfully coordinating two daylighting blasts on the same day amid the difficult geological and environmental conditions of the Lower Dibang Valley.

With this, the project has now completed breakthroughs in three of the five diversion tunnels, following DT-3 in February. The 2880 MW Dibang Multipurpose Project is a critical national hydroelectric initiative. The final blasts were witnessed by Narender Kumar, Executive Director, NHPC, who appreciated the team’s technical resilience and commitment to engineering excellence.

The Lot-02 scope includes a 37-km access road network, two permanent bridges and five diversion tunnels totalling 6.4 km. The milestone reflects the project team’s execution capabilities in complex underground construction and marks further progress towards strengthening India’s sustainable energy infrastructure.