A major milestone has been achieved in the construction of the Siddhababa Tunnel, as the invert work along the entire length of the main tunnel has been completed.

According to the Siddhababa Tunnel Project Office, the invert and lining work inside the tunnel had begun after the breakthrough of the main tunnel on January 24, 2025.

According to Krishna Raj Adhikari, the project chief, the invert construction had been completed along the full length of the 1,089-metre tunnel. He also stated that the lining and electrification work is progressing at a rapid pace.

So far, 834 metres of lining work has been completed, 388 metres on the northern side and 446 metres on the southern side. Adhikari said that the remaining 255 meters of lining will be completed within a few months.

Key components of the Siddhababa Tunnel Project include constructing the main tunnel, penetrating all four bypass doors, completing the lining work, and stabilising the hills outside the tunnel. Among these, the main tunnel and three of the four bypass doors have already been penetrated.

The project office has stated that the primary lining work is expected to be completed within next few months. Once that is done, major tunnel-related works will be completed, said project spokesperson Sabita Gyawali. She also confirmed that invert and lining work is ongoing in all three bypass doors.

So far, the project has achieved 56 per cent physical progress and 50 per cent financial progress. However, work on stabilizing the vulnerable hills on the northern and southern sides of the tunnel has not progressed as expected. Additionally, the agreement includes building a protection wall to safeguard the Siddhartha Highway from the Tinau River, which is still pending.

Translation from Gorkhapatra Daily