Print Edition - 2017-06-24 | News
Landslides ‘are common’ but can they be prevented?
- Travel woes along muglin-narayangadh road
- Measures taken to stop road disaster do not seem to be sufficient
Jun 24, 2017-
Two accidents along the Muglin-Narayangadh road section due to landslides once again have brought to the fore the vulnerability of vehicles plying the stretch, which is undergoing expansion.
Every monsoon, the busiest highway connecting Kathmandu to Tarai districts, sees a rise in number of accidents due to landslides that kill scores of people.
Though landslides are more common during monsoon, the region through which the highway passes also sees dry landslides.
In April, two persons were killed and as many injured when rocks fell from the hillside burying four vehicles at Ghumaune area along the road section.
Experts say geological structure, frequent movements of vehicles and vibrations emanating from equipment used for road construction have made the area more vulnerable to landslides. It is also believed that the earthquake two years ago could have loosened the soil in the area.
A study jointly conducted by Bhupati Neupane and Danda Pani Adhikari for the Department of Geology of Tri-Chandra College in 2011 had described geology and geological structures of the area as the main causes of landslides in the area.
Analysis of clay mineral contents, according to the study, showed that landslides with soil containing illite as the dominant component were more active than the landslides with little or no illite content in combination with chlorite and kaolinite. “Presence of high swelling clay mineral illite along with the low swelling clay minerals chlorite and kaolinite had played an important role in the occurrence and recurrence of landslides in the section,” the study said. “Rainfall, slope undercutting, land use changes (a process by which human activities transform the landscape and other human activities also trigger landslides.”
Chandra Narayan Yadav, project manager at the Muglin-Narayangadh Road Widening Project, said such landslides are very common in sloped terrain. “Adequate measures, which were recommended during the Initial Environment Examination (IEE), are being taken to minimise such landslide occurrences,” said Yadav. “We are adopting bioengineering techniques like plantation on slopes. Rock bolting is also being done. We are constructing breast walls along the slopes and removing loose soils to prevent landslides,” added Yadav. “However, three-four metre-high walls aren’t enough to stop debris falling from hillside, so stones and rocks have to be removed manually.” Many argue that the ongoing road widening project also has contributed to landslides.
The project to widen 36-kilometre started in 2015 and is in its 25th month. It was expected to be completed in two years, but now the deadline has been extended to December-end.
Published: 24-06-2017 07:27