How construction muck worsens flood damage in Himachal

At around 2 am on July 25, residents of Palchan village in Himachal Pradesh’s Kullu district woke up to a disaster. Water levels of Sarehi nala, a stream that flowed next to the village, had risen dramatically due to a cloudburst upstream.

The overflowing water and debris completely washed away three houses and about 20 sheep, before residents were moved to safer places.

While Himalayan rivers naturally carry sediments and silt, the debris in Sarehi nala had a different source – a muck-dumping site of the 9-km Atal Tunnel, situated on the Manali-Leh highway. An incident report prepared by Manali’s tehsildar and seen by Scroll noted, “huge boulders and debris from the Atal tunnel dumping site were flowing with the water due to which the flow of the Naala was changed and the course diverted towards the Palchan-Solang Naala road”.

Such muck dumping sites are common in the Himalayas. While carrying out construction for roads, tunnels and other development projects, proponents often acquire additional land for sites to dispose of the excavated debris. As a part of their detailed project reports, proponents also have to prepare a muck disposal plan that explains in detail how much muck is expected to be excavated, and the measures proposed to stabilise the debris, such as crates or retaining walls, or trees planted on the site to prevent erosion.

When muck and boulders dumped at sites are not properly stabilised with retaining walls or plantation, heavy rains can cause them to wash away. A report by the National Institute of Disaster Management noted that the mixing of muck in heavy flowing water “aggravates erosion and flooding” because of the “meandering and cutting force” of the boulders and other debris. In fact, the report, while assessing the causes of the catastrophic 2013 Uttarakhand floods found that “the muck dumped by the 330 MW Srinagar hydroelectric project might have intensified the factors responsible for the downstream damage”.

Failure of companies

Such incidents are not uncommon in the mountains. In Sainj, in Kullu district, a landslide last year damaged almost 50 houses. A “post disaster needs assessment” report by the state disaster management authority found that a dumping site about a kilometre upstream of the landslide had made matters worse. “The rise of river water coupled with higher flow velocity eroded the dump material leading to more damages to the civil structures and river bank downstream in the form of attrition and abrasion,” the report found.

Both the Himachal Pradesh Pollution Control Board and the state’s high court have taken note of the problem. Between them, they have fined private and government agencies and issued show-cause notices for illegal dumping in the Bhakra Nangal reservoir, rivulets, and forest areas.

Praveen Bhardwaj, a disaster management specialist at Himachal Pradesh’s disaster management authority told Scroll that often, companies fail to adequately implement measures to stabilise the muck they deposit. “While proponents carry out investigations and follow muck disposal plans that they include in their detailed project reports, they make the dumped material stable only for the time being,” Bhardwaj said. He added that “What is required is to secure it with a retaining wall, which is often missing.”

This year, in Mandi district, debris that collected after a cloudburst blocked two gates of the Pandoh dam. For around two days, the 990-MW hydropower project ceased operations “because there was so much debris and timber that had flowed in”, said Joginder Walia, a resident of Mandi and convenor of the Fourlane Sangharsh Samiti, a campaign of those affected by ongoing lane-widening projects in the state. “While rivers carry natural sedimentation, a lot of the debris is also a result of muck flowing from disposal sites of the projects.”

Walia said that the Samiti had repeatedly raised the issue of muck dumping sites close to the Beas river, which flows through Mandi district. Companies responded by saying that they were throwing the muck at designated points. “But in practical terms, we see that they have thrown it everywhere,” Walia said. In some instances, Walia noted, action had been taken against offenders – in 2017, for instance, the state forest department fined the National Highways Authority of India Rs 5 lakh for dumping muck in forest areas and in the Beas during road widening work.

Challenges of siting

The problem is not merely that proponents dump muck in unassigned sites or fail to stabilise it. It is also the limited availability of sites. “In mountains in general, there is a geographical constraint with landforms and existing land use,” said Manshi Asher, a researcher-activist with the Palampur-based Himdhara Environment Collective. “Which then leaves the riverside or open forest land as the only spaces available for muck generated from all construction activity.”

The Himachal Pradesh High Court and the state’s disaster management authority have both noted concerns about the problem of finding sites for disposal of muck from development projects.

The 2023 state disaster management authority report said that “debris is dumped indiscriminately on the hills. During rains, the debris is washed on the roads causing slush and muck on roads, hindering traffic movement.”

The court also highlighted the problem in 2023, in response to a public interest litigation by a panchayat member in Chamba, who alleged that muck of ongoing road construction was being dumped in catchment areas of a stream, causing damage to the houses, government buildings and agricultural fields. The court found that five of the designated sites were indeed in the catchment areas of the nala, and “such locations could be disastrous”. It observed that “if there is heavy rain, the muck from the designated sites would flow into the catchment areas and block it.”

Asher explained that judicial interventions were important to ensure that regulatory agencies were carrying out safety and environmental compliance monitoring, and subject them to punitive action if they were not. But she explained that “the nature of the problem is wider”, and that “dealing with muck adds to the cost of the construction, and contractors want to cut or externalise these costs”.

The solution, she noted, lies beyond muck management. “There is a need for land-use planning and flood-risk assessment at the watershed level,” she explained. Such measures would help the administration take informed decisions about the nature of development at different sites, after considering geological stability more broadly. This would allow them to evaluate factors such as “disturbance to slope, trees cut, quantity of debris”, Asher added.

Scroll emailed queries about the problem of muck aggravating flood damage to the Border Roads Organisation, which built and manages the Atal Tunnel, the Himachal Pradesh State Pollution Control Board and GVK Energy, the proponent of the Srinagar hydroelectric project. This story will be updated if they respond.