83 spots to get cover ahead of monsoon: NHAI opts for green mesh cover to curb landslides on Kalka-Shimla highway

Indian Express

2 days ago

Giant drilling machines piercing the hills, iron rods driven 12 to 15 metres deep, and green mesh nets spread like carpets over slopes — these are now familiar sights along the Kalka-Shimla highway, part of the 120-km-long Chandigarh-Shimla Expressway.
To preserve the natural beauty of the hills and reduce landslide risks ahead of the monsoon season, the National Highways Authority of India (NHAI) has launched slope protection works using green mesh netting, standard drilling, and anchoring at 83 vulnerable sites along a 60-km stretch between Parwanoo (Solan) and Kathlighat (Shimla) for the first time. Of these, 81 sites are on hill slopes, and two—Chakki Mod and Datyar—are on valley sides. The work, estimated at Rs 200 crore, is scheduled to be completed by March 2026.
This marks a shift from the earlier shotcrete technique, in which concrete was sprayed onto slopes, leaving behind barren cemented walls—especially visible along the Solan bypass.
'Shotcrete did help reduce landslide risks, but it wasn't nature friendly and didn't suit the biodiversity of these hills,' said Akshaya Acharya, geologist consultant to NHAI, adding, 'We used it between Sanwara and Kasauli and extensively on the Solan bypass. While technically effective, it hindered vegetation.
In contrast, the current method allows greenery to return without soil erosion.'
At the highly landslide-prone sites of Chakki Mod and Datyar, slope protection also includes the construction of reinforced soil walls. 'Unlike shotcrete, which needs no maintenance, the mesh netting technique requires regular watering to keep soil moist and promote vegetation,' Acharya said, adding, 'We will also install pedometer sensors with accelerometers at Chakki Mod and Datyar to detect underground vibrations and issue early landslide warnings.'
Sources said that the project was initially meant for only 21 sites in the Parwanoo-Solan stretch but was later expanded to 83 across two sections: Parwanoo to Solan, and Solan to Kathlighat.
NHAI Project Director (Kalka-Shimla) Anand Dahiya said, 'Around two dozen of the 83 sites are highly vulnerable. We are prioritising these ahead of the monsoon, which will naturally support vegetation growth under the mesh nets.' He added that shotcrete is also more expensive than the current mesh-and-anchor method.
The Kalka-Shimla highway has seen frequent landslides during monsoons, particularly in 2019 and 2023. Over 128 landslides were recorded—78 in 2019 and 50 in 2023—causing prolonged road blockages.
Shimla resident Raghuvir Chandel said, 'Shotcrete kills the beauty of the hills. You drive through greenery and suddenly see barren concrete walls — it's jarring. Even net meshing involves drilling and cement-filling, but it's still better than turning the entire hill into concrete.'