The Darma, Vyas and Chaudas valleys were cut off from the rest of the border districts on Thursday after a 48-metre-long concrete bridge was washed away following heavy rains.
The bridge was built over the Kulagar rivulet on the Tanakpur-Tawaghat national highway, close to the Indo-China border, Dharchula Sub-Divisional Magistrate (SDM) AK Shukla said.
A trek route has been developed as a substitute by the Border Roads Organisation (BRO) for the time being, he said.
Transshipment is being done along a 100-metre area to reach either side of the breached road, Shukla said.
The BRO has said a Bailey bridge will be built as an alternative within five days to resume vehicular movement to the border valleys, he added.
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