Floods in Jummagad river in the border area of Chamoli district of Uttarakhand has washed away the bridge built on it, blocking the Indo-Tibet border road there while contact with over a dozen border villages has also been lost.

Flooding in Jummagad river flowing near Jumma village on the Joshimath-Niti highway, about 45 km from Joshimath, continued till late night on Monday evening, during which the bridge collapsed.

The Chamoli district administration on Tuesday said motor connectivity to Kaga, Garpak, Dronagiri, Jellum, Kosa, Malari, Mahargaon, Kailashpur, Prakiya, Bampa, Gamshali and Neeti villages -- all of which lie beyond Jumma village -- were cut off after the bridge was washed away in the flood. Supply to border outposts by road has also come to a standstill.

The flood water remained above the Joshimath-Malari road, which earlier stood several metres above the river, for a long time. Eyewitnesses say that mud and heavy stones were also flowing in the flooded river.

There has been no official comment on the reason for the abrupt flooding in the river but it is being speculated that landslides in the upper reaches could have stopped the flow of the river, and flooding could have been caused when the water flow found a release later.

Others point to the possibility of the melting of glaciers in the upper catchment area of the river for the flood.

Locals are also wary of the possibility of a hydropower projects in the area and said it could increase the intensity of floods in the area. State Chief Secretary Sukhbir Singh Sandhu recently met the officials of the Prime Minister's Office to discuss the construction a big hydropower project, which has been on hold since the floods in 2013.