Road links between north and east Sikkim, snapped during the flood in October last year, have been restored partially with permanent connectivity expected by April next year, a senior Border Road Organisation (BRO) official said.

The restoration work has commenced in all the damaged stretches of Sikkim but these roads can bear only a 20-tonne load currently and not the usual 70 tonnes, BRO's Additional Director General (East) P K H Singh told PTI in an interview.

The flood caused by the glacial lake outburst had severely damaged the main roads in the Himalayan state along the Teesta river, and the Lachen-Lachung Valley ahead of Chungthang was cut off from the mainland, he pointed out.

Roads from Chungthang to Lachen and Naga to Toong were completely washed away along with bridges at Zeema, Chungthang and Toong, the lifelines of north Sikkim, completely damaged, Singh said.

The catastrophe wreaked havoc on all the lines of communication leading to north Sikkim, he said.

A sudden cloud burst over Lhonak Lake in north Sikkim had resulted in a flash flood in the Teesta river in October, leaving at least 50 people dead and scores missing.

"Restoration work has commenced on all the stretches in Sikkim with a temporary road up to Toong bridge for carrying materials being constructed," he said.

A 190 ft-long bailey bridge was constructed at Chungthang in November last year and the road up to Lachung opened for traffic even though very heavy vehicles have not been allowed, he said.

A 300 ft modular bridge will be launched by February this year to keep the road open during the monsoon season, Singh added.

"A footbridge has been built at Toong with the help of the local population and a 400 ft long modular bridge will be inaugurated by February 23 this year in the area", the official said.

Blockades due to 10 landslides between Lachen and Zeema have been cleared, he said.

Meanwhile, the construction of a modular bridge at Sanklang is underway and it is scheduled to be ready by March 31.

"The aim is at establishing permanent connectivity with North Sikkim by mid-April next year though the construction of permanent bridges may take two to three years," Singh said.

Restoration and construction activities in the high altitudes are a "major challenge as the "work window frame is very less of about four months with snow and monsoons making it extremely difficult," he said.

The Teesta III producing 1,200 MW of electricity, the biggest hydropower project in Sikkim, located in Chungthang town of Mangan district, was completely decimated by the glacial lake outburst flood.

Even the approach road to the Theng tunnel in North Sikkim was severely damaged, he said.

The BRO kept the alternative roads to Gangtok, Algarh and Rongli open for traffic immediately, following the catastrophe to ensure uninterrupted movement of essential commodities to North Sikkim, he pointed out.

"The immediate action done by the BRO after the disaster was to evacuate civilians and tourists along with mobilising resources on a war footing," he said.

An alternative route to Chungthang was opened by constructing two bailey bridges over the Teesta River by October-end along with repairing a large number of landslides and sliding areas on main roads, the ADG said.

More than 15 footbridges, zip lines and aerial cableways were constructed in coordination with the army, ITBP and civil administration, Singh added.

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