Vehicles stranded on Sevoke Road. A Telegraph picture

Siliguri, March 17: Just a millimetre of rain and the hill above Sevoke Road came crashing down.

In a tell-tale sign of the precarious nature of the Himalayan foothills, a landslide struck national highway 31 at Sevoke ? about 20 km from here ? following 1 mm of rainfall caused by a ?cyclonic disturbance? last night.

Marking the beginning of the ?landslip season?, the slide took place at 4.30 in the morning. The debris formed a 4-ft hump, spread over a 15-metre stretch between Coronation Bridge and the Sevokeshwari Kali Temple, cutting off the main routes to Sikkim, Kalimpong and the Dooars from Siliguri for over seven hours.

The General Reserve Engineering Force (Gref) of the Border Roads Organisation cleared the debris well after noon, following which the pile of traffic could move again.

Dynamites were kept as a standby arrangement to clear the road, but were not used.

?I was stranded since six in the morning,? said Raju, one of the first drivers to reach the spot. ?When we reached, we saw the stretch covered with boulders, stone and loose earth. There was no way we could make a way and cross to the other side,? he said.

The line of waiting vehicles stretched about 4 km on either side of the rubble by the time the highway was finally cleared.

Subir Sarkar, the man in charge of North Bengal University?s weather station, said the slip was only a pointer to the extent of environmental degradation the Himalayas were facing. ?It may have been caused by reasons other than just the rain, which need to be studied,? he added.

He also sounded the alarm. ?The major worry is to try and gauge the extent of damage the monsoon might trigger.?

Earlier, there were only three points on the road to Kalimpong that were slide-prone. ?Now, the entire stretch has become vulnerable. A long-term conservation plan is the need of the hour and if that is not worked upon, the situation will only worsen,? said Sarkar.