The Rs7.34 billion Siddhababa tunnel project is all set for a breakthrough.

According to project officials, the 1.12-kilometre tunnel project on the landslide- and rockslide-prone Butwal-Palpa section of the Siddhartha Highway is set to achieve its final breakthrough in the first week of January.

Two of the three bypass cross passages have been completed along this busy highway, which connects the hill districts of Lumbini and Gandaki provinces to Butwal and several Tarai districts.

According to the project, the first bypass, spanning 151 metres, and the third bypass, measuring 130 metres, have been completed, and 165 metres of the major tunnel work remains to be completed.

The project office said that 961 meters of digging on the north and south ends of the main tunnel were completed by Wednesday. Work on the main tunnel is being carried out simultaneously from both ends.

“Workers are busy in the main tunnel,” said Krishna Raj Adhikari, the project's chief.

The first bypass links the upper Siddhababa temple, and the third bypass connects to the Dobhan dam side.

The section, notorious for its dangers, has claimed many lives, prompting the government to construct the tunnel. Over the last decade, at least 421 travellers have lost their lives, and many others have sustained injuries in numerous accidents on the treacherous 4-km road section, according to the District Traffic Office, Palpa.

More than 10,000 vehicles ply the road section every day.

The China State Construction Engineering Corporation signed the contract in March 2022 with a completion deadline of five years.

The project is being constructed under the engineering, procurement, and construction (EPC) model, where a single contractor is responsible for all components, such as design, engineering, construction, and procurement.

The contract binds the contractor to deliver the project within the stipulated timeframe and at the predetermined price, regardless of any possible cost overruns.

According to the project office, the tunnel's physical progress has reached 33.59 percent, and its financial progress is at 32.2 percent.

“As we are actively working for the main tunnel breakthrough within a month, we have ramped up manpower and resources,” said Adhikari.

He said the project has sufficient blasting material in stock, and the construction company has deployed around 150 workers at the construction site to keep the project on track.

The tunnel design has progressed as planned. “We have also strictly followed safety measures while widening the road,” said Adhikari. “The work inside the tunnel is progressing rapidly, but work on the outside has yet to start as efforts are underway to control landslides outside the tunnel.”

“Rock shed and road designing works are also moving ahead smoothly,” said Adhikari.

A rock shed is a protective structure built over a road or tunnel to shield it from falling rocks and debris. This protective covering redirects the falling material safely away, reducing the risk of accidents in landslide-prone areas.

To stabilise the hillside around the tunnel in the Siddhababa area, a rock shed has been constructed over 1495 square metres, and work is underway to protect an additional 495 square metres on the northern side.

The China State Construction Engineering Corporation was awarded the tender worth Rs7.34 billion. Besides a rock shed, the contractor will also construct rock fall netting and slope protection structures on the outer side of the tunnel.

As per the detailed project report prepared with assistance from the Swiss Agency for Development and Cooperation, the 1.12-kilometre tunnel will have double lanes with a width of 8.5 metres along with sidewalks. Around 900 meters of the double-lane road will link to the Chidiya River on the Butwal side and 560 meters will connect to the Palpa side.

The Siddhababa-Dovan road section is the main link between more than a dozen districts in the plains and hills such as Palpa, Gulmi, Arghakhanchi, Syangja, Kaski, Parbat, and Baglung.

The tunnel is expected to provide safer and easier travel along the highway between the distrticts of Lumbini and Gandaki provinces.