As rains triggered by the remnants of Cyclone ‘Motha’ lashed north Bengal from Friday (October 31, 2025) and continued to batter the hills until Saturday (November 1, 2025), experts warned that unregulated construction and tourism in this ecologically fragile region are increasing the risk of floods and landslides.
Earlier in October, incessant rainfall in the area had claimed over 30 lives and caused more than 110 major landslips, bringing life to a standstill.
In many areas in North Bengal, the rivers are flowing near or above the danger mark, raising panic among the locals who are still recovering from the last disaster. A temporary bridge at Dudhia had to be closed due to safety concerns as the Balason River soared. The iron bridge on the river was damaged in the October 5 flash floods.
On October 5, the hills of West Bengal witnessed one of the worst natural disasters to have affected the area in over 30 years. The overflowing rivers and relentless downpour wreaked havoc across the Darjeeling and Jalpaiguri districts, killing people and destroying homes, roads, and bridges. Many roads in the areas are still blocked as rebuilding of roads and bridges continues.
After the disaster struck earlier in October, the West Bengal government officials, including Chief Minister Mamata Banerjee, blamed the unprecedented rain, poor flood management by the Central Government, and excessive flow of water in the Sankosh River from Bhutan and Sikkim for triggering the disaster.
Impending disaster: warn experts
However, experts believe that incessant rain and dam water release may not be the sole reason behind the disaster that took multiple lives in the hills.
“Rivers, streams, and waterfalls are the natural drainage system of a mountain, but these are being blocked or rerouted due to construction and heavy silt deposition. Once they are blocked, flash floods can occur very easily because the carrying capacity of the water bodies is reduced,” Partha Pratim Biswas, professor of construction engineering at Jadavpur University, told The Hindu.
Prof. Biswas raised questions about why hotels are cropping up on the banks of rivers and why construction is allowed in these vulnerable locations. He highlighted that the craze for “off-beat tourist destinations” is promoting the unregulated construction of hotels and homestays right beside the rivers.
Experts also added that rainfall patterns are also changing due to global warming and climate change, leading to unprecedented heavy rains within a short period of time. Like in the intermittent night of October 4-5, when north Bengal received 261mm of rainfall in just 12 hours, triggering the floods and landslides. To prepare for such situations, experts said that the carrying capacity of rivers must also be increased by dredging, desilting, and stopping construction along the most vulnerable riverbanks.
“Each hill slope is different; each slope needs to be scientifically studied, and if the rock soil formation of the hill does not permit construction, we must declare it as a ‘no construction zone’, but there is no such regulation here,” Prof. Biswas added. He also warned that heavy construction on steep slopes makes both the hills and the structures unstable, and when it rains, it can slide the whole structure and crush it.
Deforestation of mountain forests has also become common to promote the easy construction of houses and hotels. However, Prof Biswas warned that the roots of trees act as natural geo reinforcements, binding the fragile mountain soil, preventing erosion and landslides, and once they are axed, the mountains crumble swiftly.
Experts also warned against the rapid highway and tunnel construction in the north Bengal hills to ease the commute of tourists and locals. “At least 200 metres along both sides of the river is supposed to be a River Regulated Zone (RRZ) to ensure the river’s natural flow and ecology and maintain flood-carrying capacity. So, when it rains, and the river swells, it is bound to wash away all the inhabitants and houses that are constructed on the riverbed,” Indrajit Roy Chowdhury, assistant professor of geography at North Bengal University, warned.
Prof Roy Chowdhury also added that in an attempt to promote renewable energy resources through hydropower projects, the construction of dams along the Teesta River has also reduced its carrying capacity.
Way forward
“Unmonitored construction at vulnerable locations must be checked to see if they are following the government protocols to ensure sustainable tourism in ecologically sensitive zones,” Samrat Sanyal, secretary of the Himalayan Hospitality Tourism Development Network, said. He also added that they are running a detailed survey across the mountains of North Bengal to see if sensitive areas are exceeding their carrying capacity and submit a report with the government of West Bengal.
Tourism experts in the hills called for a rethought model of tourism which is more sustainable and promotes ecologically sound structures to avoid such disasters in the future which led to both loss of lives and livelihood this year.
Scientists also highlighted the urgent need to map the hills in north Bengal to see which hill promotes which type of construction and implement strict regulations based on the findings to ensure that nature and people can peacefully co-exist.
“We cannot simply keep thinking about profits. There is an urgent need to take a more holistic approach to promote sustainable tourism in the hills so we do not lose our nature and people to bigger natural disasters,” Prof. Roy Chowdhury added.
Published – November 02, 2025 08:29 am IST
