Why Zoji La keeps sliding into danger

Srinagar, Apr 29: Fragile snow layers, steep slopes, and fluctuating temperatures are making the high-altitude Zoji La a frequent site of avalanches, according to experts.

An avalanche on April 25 struck the Srinagar-Leh National Highway at Shaitan Nallah, near Drass leaving several vehicles stranded and forcing traffic to be halted.

No casualties were reported.

The incident followed a March 28 avalanche in the same region that killed seven people. Several smaller avalanches have also been reported over the past month.

The route has long been vulnerable and has seen multiple fatalities over the years.

At an altitude of about 11,575 feet, the pass combines natural conditions that favor avalanches.

Slopes in the area generally range between 30 and 45 degrees, considered the most prone for snow slides, while limited vegetation leaves the snowpack without support.

“Heavy snowfall during winter builds thick layers of snow that are often weakly bonded,” said Riyaz Ahmad Mir, a geologist with the National Institute of Hydrology in Jammu. “Wind further loads these slopes, creating instability within the snowpack.”

Mir said weak layers beneath fresh snowfall are a major trigger.

“When new snow settles over older, fragile layers, even minor disturbances can lead to a collapse,” he said.

Rising temperatures in spring add to the risk. As the snow begins to melt, moisture seeps into the layers.

“Meltwater acts as a lubricating agent, reducing friction and increasing the chances of avalanches,” Mir said, adding that rugged terrain and even traffic vibrations can act as triggers.

Meteorological factors also play a role, said Mukhar Ahmad.

“Early melting, weak snowpack layers and fresh snow in spring increase the likelihood of avalanches,” Ahmad said, advising travellers to follow weather advisories before using the highway.

Several stretches along the route, including Shaitan Nallah, are identified as long-term avalanche-prone zones where incidents recur under similar conditions.

The Srinagar-Leh National Highway, which runs through Zoji La Pass, has remained susceptible to weather disruptions for decades.

Authorities are working on the Zojila Tunnel, a 14.2-km all-weather tunnel expected to provide year-round connectivity between Kashmir and Ladakh and reduce reliance on the avalanche-prone pass.