Geologist Krishna KC said the depth of the river has been increasing by the day and has been eroding the surface beneath the banks. “The mounds on the river banks are barely clinging on,” he said.

Analysing the frequency of sinkholes that have appeared in Armala VDC, KC said it is high time that the authorities concerned came up with some strategy to tackle the problem at the earliest. He said the depth of the gorges is increasing at the rate of four metres each year, making the city prone to natural calamities like sinkholes, flood and earthquake.

KC suggested forming a committee comprising all the stakeholders to regulate sand and stone mining and said Pokhara Sub-metropolis and the District Development Committee (DDC) should take initiatives to save the city.

Meanwhile, the haphazard development of the city over the past three decades and the lack of proper regulations and building code violation have added to the existent threat.

Soil erosion caused by unmanaged mining of sand and gravel has already started destroyed houses alongside the river banks in Hemja, displacing local people.

Even millions of rupees invested in constructing the embankment at Ramghat has been wasted after its foundation crumbled owing to loose land beneath.

Although a geological survey conducted in 1998 had stated that areas within 100 metres of both sides of the river were at risk, illegal sand and stone mining in the same areas has gone unchecked for years owing to the negligence of the concerned authorities. “Settlements near the river are at risk as soil erosion triggered by rampant excavation of sand and gravel and the only way of protecting the areas is to construct a dam from Kotre in Tanahun,” said Shiva Shankar Shah, an overseer at the Soil Conservation Office in Pokhara.

One can observe hundreds of people working alongside the river banks throughout the year. More than 500 labourers can be seen excavating sand each day at Ramghat alone. But the authorities concerned have remained mute spectators.

Sitaram Gharti of Sindhuli, an excavation labourer who started the profession four years ago, said he and his men excavated 16 trucks of sand and gravel in a month.

Admitting that they had failed to control the rampant mining of sand and gravel, the DDC’s Information Officer Nishan Raj Gautam said they are working to regulate such activities.

Currently, mining of sand and gravel is under way as many as 35 sites and almost all of them are operated by so-called dons who get the tender in their names by any means necessary.

The DDC has been collecting millions of rupees in revenue each year from the contractors. The DDC collected approximately Rs 30 million in revenue in this fiscal year alone and aims to collect Rs 50 million next year.