Nepal government has invited international bids to upgrade the 70-km Narayangadh–Hetauda road, a major highway linking central Nepal’s industrial hub with the country’s main east-west transport corridor.

The international open bidding process was launched on September 4 for the section from the Rapti Bridge in Hetauda to Gondrang in Bharatpur, Chitwan.

The 70-km highway will be upgraded to four lanes and divided into three packages, with the first covering 40 km in Makawanpur district, the second 26 km from Makawanpur to Tikauli in Chitwan, and the third the four-km stretch from Tikauli to Gondrang.

Contractors will have three and a half years to complete the work after the contract is signed. Chuda Raj Dhakal, project director at the Project Directorate (ADB) under the Department of Roads, said the bidding process would take more than seven months to complete, sign the contract, and begin construction.

A two-km flyover will be built through the Tikauli forest in Chitwan, allowing traffic to pass above the protected area while wildlife can move underneath. Dhakal said it would be the first flyover of this length built inside a protected area in Nepal.

“The flyover is being designed with wildlife movement in mind,” Dhakal said.

Seven permanent bridges will also be built along the Makawanpur–Chitwan section. The road upgrade is being financed through concessional loans from the Asian Development Bank.

The flyover alone is estimated to cost Rs5.5 billion, of which Rs3 billion will come as an ADB grant. The remainder will be financed through ADB’s concessional lending.

The flyover will have four traffic lanes, with two lanes carrying vehicles in each direction. A separate lane on either side will be provided for pedestrians and cyclists.

The structure will stand on 67 pillars, with vehicles travelling on top while wildlife will be able to cross underneath. Major bridges are planned over the Rapti, Lothar and Manohari rivers.

Across settlements along the Hetauda–Narayangadh section, the upgraded highway will have four traffic lanes and a single service lane on each side. In urban areas, the road will include four traffic lanes, two service lanes on either side, drains and pavements.

Rural sections will also have service lanes, unlike many existing roads in the eastern part of the country, although pavements will not be provided in rural areas, Dhakal said. Through forested areas, the highway will be widened to four lanes.

An alternative route through Muglin

Work is also progressing to upgrade the road between Aanbukhaireni and Pokhara, with some sections already completed and others nearing completion.

The section towards Aanbukhaireni was not included in the first phase of the four-lane expansion because the existing road is narrow and widening it would pose significant engineering risks. The area also carries heavy traffic and contains the powerhouse of the Marsyangdi hydropower project, making further hillside cutting particularly difficult.

Instead, the project will build a two-lane road on each side of the existing corridor.

According to Dhakal, an 8.5-km section below Muglin Bazar will be rerouted, with about five km of the new road built on the opposite side of the river. The section will include two major and three smaller bridges under a design-and-build contract.

One major bridge will be built below Muglin Bazar and another immediately after the road passes the Marsyangdi hydropower project’s powerhouse. A permanent bridge will also be constructed about 400 metres from the powerhouse, after which the road will continue towards Jamune as a four-lane highway.

“The bridges in this section will be contracted under a design-and-build model. It took some time to reach agreement on the tender documents,” Dhakal said. “We will award the contract within a month.”

The project estimates that the work on this section will cost about Rs4 billion.

Overall, the Narayangadh–Hetauda and Aanbukhaireni–Marsyangdi road projects are expected to cost about Rs45 billion, Dhakal said. “The funding will also cover road safety and maintenance work on the Karnali Highway.”

Hetauda bypass takes shape

The 30-km road between Pathlaiya in Bara and Hetauda is also being upgraded with ADB financing.

A bypass around Hetauda is currently being designed, while designs for the remaining sections have already been completed, Dhakal said.

“The design for the Hetauda bypass is underway,” he said. “The other sections are ready, but awarding the contract could take around one and a half years.”