KATHMANDU: A 4.0 km long viaduct will be constructed on the Pathlaiya-Hetauda-Narayanghat section of the East-West Highway. The project is part of the road’s upgrade to a four-lane standard.
According to the Environmental Impact Assessment (EIA) report made public by the Ministry of Forests, two separate viaducts of 2,001 meters each will be built. One lies in the Parsa National Park buffer zone and the other in the Barandabhar corridor forest in Chitwan.
The detailed project report (DPR) has already been prepared under the Department of Roads with support from the Asian Development Bank (ADB).
The total cost of upgrading the 100 km road to four lanes is estimated at Rs 54.29 billion. Out of this, Rs 10.50 billion will be spent only on the viaduct structures.
The viaduct will have four lanes, with two lanes on each side. A minimum 8-meter light gap will be maintained between parallel structures. This allows natural light and open space for wildlife movement below.
Each structure will be 11.75 meters wide. It includes an 8-meter carriageway and a 2.75-meter footpath. Safety barriers and crash guards will also be installed. The minimum height of the viaduct will be 7 meters, allowing large animals like elephants and rhinos to pass safely.
Special noise and light barriers will be installed to reduce disturbance from vehicle headlights and engine sound. Around 14 km of fencing in Parsa and 4 km in Barandabhar will be built. This will guide wildlife towards safe crossing points.
The road will be upgraded to Asian Highway-2 standard. Vehicles are expected to run at speeds of 80-100 km/h.
The road width will vary by location. It will be 50 meters in urban areas, 37.4 meters in semi-urban sections, and 24 meters in rural and forest zones.
The project stretches from Pathlaiya in Bara to Gondrang in Chitwan, covering 19.52 km in Bara, 50.15 km in Makwanpur, and 30 km in Chitwan. It includes 19 animal crossings and 24 canopy bridges to support wildlife movement.
A total of 41 bridges will be part of the project, with 22 existing structures upgraded and 19 new bridges constructed. Additionally, 246 culverts will be built. In urban areas, 6 skywalks and 12 underpasses are planned for pedestrian movement.
The design follows standard return periods, with 100 years for bridges, 50 years for culverts, and 25 years for side drains.
Construction is expected to be completed within three years. The government aims to award the contract by 2026.
23,500 trees set to be cut down
A total of 23,326 trees will be cut during the project. The breakdown includes 9,646 in Bara, 10,278 in Makwanpur, and 3,402 in Chitwan. For each tree cut, 10 saplings will be planted. Around Rs 222.6 million has been allocated for plantation.
The project will affect 403 private structures from 378 households and 180 community structures. However, no additional land acquisition is required as work will remain within the existing 50-meter right of way.
The upgrade aims to reduce traffic congestion, shorten travel time, and improve road safety.
The Ministry of Physical Infrastructure and Transport has submitted the EIA for approval. The Ministry of Forests has invited feedback from stakeholders until April 3, 2026.
