Latest news with #WadiaInstituteofHimalayanGeology
The Print
a day ago
- General
- The Print
Dharali disaster not isolated incident, need to study settlements present on river banks: Experts
Dr. Sushil Kumar, former senior scientist at the Dehradun-based Wadia Institute of Himalayan Geology, said, 'Now the time has come to study all those areas where large settlements have come up on the headlands of rivers and streams.' Headlands are the plains situated on the banks of the river which are covered by floods from time to time. These plains are usually made up of soil, silt, sand and gravel deposited by the river. The experts say that the Dharali disaster should not be seen as an isolated case. Dehradun, Aug 8 (PTI) Four days after raging waters buried half of Dharali village in Uttarkashi, experts have stressed the need to study the existing settlements located on the river banks or in the flood plains. Due to the high amount of nutrients, this land is fertile, which makes it very useful for agriculture and because of this, villages and settlements are also established in these areas, but they are often at risk of floods. Many scientists including Dr. Kumar say that the debris-laden water stream that hit Dharali was on its original path and destroyed all the hotels, homestays, restaurants and houses that came in its way. In view of the boom in tourism in the last few years, dozens of hotels, restaurants and homestays have mushroomed in Dharali and most of the buildings destroyed in the disaster were built in violation of environmental rules on the banks of the Khirgad seasonal river, they said. This disaster, which struck on August 5, turned a beautiful stop on the way to Gangotri Dham into a high pile of rubble in the blink of an eye. Locals say the government also turns a blind eye to violation of norms in environmentally sensitive areas, including a ban on new construction along the Bhagirathi riverbank. In 2023, a large building of a training academy collapsed like a pack of cards amid heavy floods in the Song River in Maldevta area of Dehradun. Experts say that the building was constructed on the river bank in gross violation of environmental norms. Environmentalist Anoop Nautiyal said that the most glaring example of violation of environmental norms in construction is present in Dehradun where the Uttarakhand Assembly building has been built right on the banks of the Rispana river. In the last few years, dozens of colonies including Bhagat Singh Colony have been built by encroaching on the banks of the Rispana and Bindal rivers in Dehradun. The locals have alleged that in most cases, government officials are in collusion with land mafia and buildings are constructed on the vacant land. Many petitions have been filed in the Uttarakhand High Court regarding the damage to the environment due to illegal construction in Dehradun, Rishikesh and other areas. The High Court has also directed the state government to remove encroachment from the land along the banks of Rispana and Bindal rivers. PTI DPT NB This report is auto-generated from PTI news service. ThePrint holds no responsibility for its content.
The Hindu
2 days ago
- Climate
- The Hindu
Uncertainty prevails over the cause of Uttarkashi flash floods
Days after heavy rains triggered a flash flood and an avalanche of debris that deluged Dharali in Uttarkashi, Uttarakhand, uncertainty prevails over what caused the disaster. As of Thursday (August 7, 2025), rescue and relief operations in Uttarkashi to extract those stranded, and accounting for those missing, has meant that scientific investigations into the cause of the disaster have not yet begun. Follow Uttarkashi flash floods rescue operation LIVE updates 'We are planning a reconnaissance but, currently, accessing the sites is difficult. Rainfall data that we have from the India Meteorological Department (IMD) suggests that this was not a cloudburst,' Vineet Kumar Gahalaut, Director, Wadia Institute of Himalayan Geology, Dehradun, said. 'It is possible that there is a glacier lake overflow or heavy rain triggering a landslide of accumulated silt and debris,' he said. The IMD too has characterised 'extremely heavy rainfall' from August 3-5 as a probable cause, but not a cloudburst. A 'cloudburst' is a more extreme form of rainfall, defined by the IMD as exceeding 10 cm in an hour over a 10 sq. km. grid, and it results from a build-up of moisture forming large cumulonimbus clouds that suddenly release all their water. These causes matter as rising instances of Himalayan disaster precipitated by extreme rainfall and changing climate help better understand potential causes, and design warning systems. While cloudbursts aren't unexpected given the prevailing monsoon conditions, they are challenging to forecast, and confirming them requires specific instruments, including the Doppler Weather Radar (DWR) that can image them, as well as Automatic Weather Stations (AWS) that can provide hourly data on the rainfall, temperature, wind, and humidity. There are three DWR (DWRs) in Uttarakhand but even between them, they leave vast stretches of the Upper Himalayas unmapped. Data from the AWSs is not publicly shared. Rainfall data from the IMD that is publicly shared only indicates eight-hourly or 24-hour rainfall data. On August 5, the day of the Uttarkashi deluge, rainfall data for Uttarakhand showed, for instance, that Haridwar (Haridwar district) reported 30 cm of rain over the previous 24 hours; Narendranagar (Garhwal Tehri district) reported 17 cm; Rishikesh (Dehradun district) 14 cm; Jolly Grant (Dehradun district) 13 cm; and Kotdwara (Garhwal Pauri district) 12 cm. While this is significant rain, it isn't known whether this was concentrated over a short duration or averaged over a day. 'While the data we have so far does not indicate a cloudburst, I cannot entirely rule it out,' M. Mohapatra, Director-General, IMD, said. 'It is theoretically possible there was a cloudburst in the upper reaches [of the Himalayas] where we do not have instruments. Satellite imagery and other remote sensing could provide some answers, and I believe that the National Disaster Management Agency is coordinating some investigation on it.' Noida-based satellite imagery company Suhora Technologies said that a 'cloudburst' was probably a cause as their analysis showed there were no glacier-fed lakes or large water bodies that had spilled over. 'We have used synthetic aperture radar (SAR) imaging from the ICEYE satellite and checked upstream of Dharali village. There is no glacier lake or water body. We have a fairly extensive database of existing glacier lakes in the Himalayas. It does look like rainfall was a trigger,' Subhajit Bera of Suhora Technologies said, adding, 'However, we don't yet have images from the upper stretches and so don't know the exact causes yet.' 'The steep terrain around Dharali village, where the tragedy occurred, acted like a chute, accelerating mud and debris into a deadly rush downhill. Just like the 2024 monsoon tragedy in Wayanad in Kerala's Western Ghats, the Himalayas too are becoming monsoon graveyards. Climate change is intensifying these extremes, since monsoon storms are now forming in a warmer atmosphere that holds and dumps far more moisture in short bursts, causing flash floods and landslides. What's worse is that many of these regions lack real-time weather surveillance and effective early warning systems,' Akshay Deoras, research scientist at the University of Reading, said in a statement. In February 2021, an ice-rock avalanche north of Joshimath in Uttarakhand, claimed 72 lives, with hundreds missing, and two hydropower projects destroyed or damaged. A glacier lake burst in north Sikkim in October 2023 damaged the Teesta-3 hydropower project in the State, claiming at least 40 lives.
The Hindu
3 days ago
- Climate
- The Hindu
Uttarkashi flash floods: Cause of disaster still unclear with sites difficult to access
Days after heavy rains triggered a flash flood and an avalanche of debris that deluged Dharali in Uttarkashi, Uttarakhand, uncertainty prevails over what caused the disaster. As of Thursday (August 7, 2025), rescue and relief operations in Uttarkashi to extract those stranded, and accounting for those missing, has meant that scientific investigations into the cause of the disaster have not yet begun. Follow Uttarkashi flash floods rescue operation LIVE updates 'We are planning a reconnaissance but, currently, accessing the sites is difficult. Rainfall data that we have from the India Meteorological Department (IMD) suggests that this was not a cloudburst,' Vineet Kumar Gahalaut, Director, Wadia Institute of Himalayan Geology, Dehradun, said. 'It is possible that there is a glacier lake overflow or heavy rain triggering a landslide of accumulated silt and debris,' he said. The IMD too has characterised 'extremely heavy rainfall' from August 3-5 as a probable cause, but not a cloudburst. A 'cloudburst' is a more extreme form of rainfall, defined by the IMD as exceeding 10 cm in an hour over a 10 sq. km. grid, and it results from a build-up of moisture forming large cumulonimbus clouds that suddenly release all their water. These causes matter as rising instances of Himalayan disaster precipitated by extreme rainfall and changing climate help better understand potential causes, and design warning systems. While cloudbursts aren't unexpected given the prevailing monsoon conditions, they are challenging to forecast, and confirming them requires specific instruments, including the Doppler Weather Radar (DWR) that can image them, as well as Automatic Weather Stations (AWS) that can provide hourly data on the rainfall, temperature, wind, and humidity. There are three DWR (DWRs) in Uttarakhand but even between them, they leave vast stretches of the Upper Himalayas unmapped. Data from the AWSs is not publicly shared. Rainfall data from the IMD that is publicly shared only indicates eight-hourly or 24-hour rainfall data. On August 5, the day of the Uttarkashi deluge, rainfall data for Uttarakhand showed, for instance, that Haridwar (Haridwar district) reported 30 cm of rain over the previous 24 hours; Narendranagar (Garhwal Tehri district) reported 17 cm; Rishikesh (Dehradun district) 14 cm; Jolly Grant (Dehradun district) 13 cm; and Kotdwara (Garhwal Pauri district) 12 cm. While this is significant rain, it isn't known whether this was concentrated over a short duration or averaged over a day. 'While the data we have so far does not indicate a cloudburst, I cannot entirely rule it out,' M. Mohapatra, Director-General, IMD, said. 'It is theoretically possible there was a cloudburst in the upper reaches [of the Himalayas] where we do not have instruments. Satellite imagery and other remote sensing could provide some answers, and I believe that the National Disaster Management Agency is coordinating some investigation on it.' Noida-based satellite imagery company Suhora Technologies said that a 'cloudburst' was probably a cause as their analysis showed there were no glacier-fed lakes or large water bodies that had spilled over. 'We have used synthetic aperture radar (SAR) imaging from the ICEYE satellite and checked upstream of Dharali village. There is no glacier lake or water body. We have a fairly extensive database of existing glacier lakes in the Himalayas. It does look like rainfall was a trigger,' Subhajit Bera of Suhora Technologies said, adding, 'However, we don't yet have images from the upper stretches and so don't know the exact causes yet.' 'The steep terrain around Dharali village, where the tragedy occurred, acted like a chute, accelerating mud and debris into a deadly rush downhill. Just like the 2024 monsoon tragedy in Wayanad in Kerala's Western Ghats, the Himalayas too are becoming monsoon graveyards. Climate change is intensifying these extremes, since monsoon storms are now forming in a warmer atmosphere that holds and dumps far more moisture in short bursts, causing flash floods and landslides. What's worse is that many of these regions lack real-time weather surveillance and effective early warning systems,' Akshay Deoras, research scientist at the University of Reading, said in a statement. In February 2021, an ice-rock avalanche north of Joshimath in Uttarakhand, claimed 72 lives, with hundreds missing, and two hydropower projects destroyed or damaged. A glacier lake burst in north Sikkim in October 2023 damaged the Teesta-3 hydropower project in the State, claiming at least 40 lives.
News18
4 days ago
- Climate
- News18
Disaster After Disaster: Why Uttarakhand Gets Caught Off-Guard Again And Again
Last Updated: Repeated disasters expose grim pattern of reckless construction, ignored warnings, and race for tourism infra that continues to cost hundreds of lives each year, say scientists On February 7, 2021, residents of a few villages in Chamoli heard loud sounds and witnessed huge amounts of mass consisting of rocks, mud, water, and ice blocks roaring down the Dhauli Ganga river, destroying parts of two hydropower plants in its path. More than 204 people lost their lives, while hundreds went missing. Two years later, over 700 houses across the holy town of Joshimath developed cracks, with water oozing out of walls and roads, exposing massive land subsidence. On Tuesday, a massive flash flood devastated Dharali village in Uttarkashi, sweeping away everything in its path, with over a hundred still missing. Just days earlier, on July 31, the state's disaster management confirmed 17 deaths from severe overnight rains, and landslides all through monsoon. Each year, the state repeats the same mistakes—cutting down forests, exposing fragile slopes, narrowing river channels and expanding construction deep into the ecologically-sensitive catchment areas. 'Uttarakhand Himalayas are extremely fragile. Rainfall is almost always the trigger. But even when rainfall is not intense, it can still cause slope failure and landslides, especially because the mountain rocks have been weathered, and weakened by repeated freezing and thawing caused by extreme temperature fluctuations. Temperatures in upper altitudes are rising more than in the plains," said Dr Kalachain Sain, former director of Wadia Institute of Himalayan Geology (WIHG), Dehradun. With rampant construction of hydropower projects, hotels, roads, and highways—all driven by a booming tourism industry—trees are being felled mercilessly, destabilising the the hills. Geologists explain how the persistent rains tend to percolate into the subsurface layers, saturating the soil and weathering rock mass. 'In areas where forest cover has been removed, there is little to hold the soil in place. The infiltrated water adds weight to the slope material, making it heavier, which gives in to even a slight disturbance and causes a massive landslide. We all know how dangerous it is during monsoons, when prolonged rainfall, even if moderate, mixes with soil and debris to cause these destructive flash floods," he added. Despite ecological concerns, large-scale tree felling, and the fragile, disaster-prone terrain of Uttarakhand, construction activities have continued unabated. A total of 2,969 kms of National Highways have been developed between 2014-15 and June 2025, Union transport minister Nitin Gadkari told Parliament this July. A centre piece of this is the Union government's Char Dham National Highway Connectivity Programme to improve road access to four pilgrimage sites of Yamunotri, Gangotri, Kedarnath and Badrinath. Dr Anand Sharma, former Additional Director-General at IMD, known for predicting the intense rains spell leading up to the Kedarnath floods in 2013, highlighted the failure to ensure early warnings. 'Cloudbursts are challenging to predict. But in Uttarakhand, even 6-7 cms of rainfall can cause water to mix with rock, sediment, soil and come crashing down the slopes. Radars should be able to detect such cloud formations, and that warning be disseminated immediately. These disasters unfold within seconds, so the response time must be immediate. Additionally, why has the construction been allowed in the close catchment areas? Most of these houses in Dharali which got washed away were so close to the stream, and recently built." Uttarakhand now has three Doppler weather radars—located in Mukteshwar, Surkanda Devi and Lansdowne—commissioned last year, which can provide data for numerical weather prediction models, particularly for nowcasting (forecast for a few hours). These were also expected to improve rainfall estimation, especially heavy rains. 'What is lacking is a coordinated response during disasters," remarked Dr M Rajeevan, former secretary of the ministry of earth sciences. 'Even if radar coverage is available, we still need adequate algorithms to predict such extreme events. Technology has advanced, and there must be automated systems to issue real-time Nowcast warnings to alert people. We can no longer afford delays between data analysis and dissemination of information. The major problem is that currently, warnings for rainfall, landslides, flash floods are fragmented – handled by multiple agencies without a unified command, which hampers timely action to save lives." view comments First Published: August 06, 2025, 15:25 IST News india Disaster After Disaster: Why Uttarakhand Gets Caught Off-Guard Again And Again Disclaimer: Comments reflect users' views, not News18's. Please keep discussions respectful and constructive. Abusive, defamatory, or illegal comments will be removed. News18 may disable any comment at its discretion. By posting, you agree to our Terms of Use and Privacy Policy.
Time of India
18-07-2025
- Science
- Time of India
Himalayas may be 40 million yrs older than thought: New study
Dehradun: Scientists at the Wadia Institute of Himalayan Geology (WIHG) have found that parts of Arunachal Pradesh in the eastern Himalayas saw intense geological activity millions of years before the Indian and Eurasian tectonic plates collided: an event long believed to have led to formation of the Himalayas around 50 million years ago. The study, funded by the ministry of earth sciences and published in the Journal of the Geological Society, revealed that a prolonged phase of volcanic and magmatic activity occurred in the Lohit and Dibang valleys around 40 million years before the plate collision. Focusing on the Lohit Plutonic Complex (LPC), a belt of underground igneous rocks, researchers used geochemical analysis and zircon U–Pb dating (determining the age of rocks by analysing the radioactive decay of uranium to lead in zircon crystals) to conclude that the activity was likely triggered by the subduction (where one tectonic plate slides beneath another) of the Neo-Tethys Ocean lithosphere beneath the Eurasian plate. The rocks in this zone were found to be chemically consistent with subduction-driven magmatic activity. "This region largely remained a blind spot in Himalayan geology," said WIHG scientist and project lead Vikas Adlakha. "Our study shows that the eastern Himalayas underwent complex geological changes much earlier than previously thought." The team also found the first definitive evidence of migmatisation in the area—partial melting of crustal rocks caused by intense heat and pressure—between 88 and 69 million years ago. by Taboola by Taboola Sponsored Links Sponsored Links Promoted Links Promoted Links You May Like Providers are furious: Internet access without a subscription! Techno Mag Learn More Undo Researchers documented characteristic light and dark bands in the LPC rocks, hallmark features of migmatites, along with other signs of deformation and deep crustal shifts that predate the tectonic plate collision. "Our zircon dating shows that the melting and subduction-related activity occurred around the same time," said Adlakha. "This suggests a major thermal anomaly in the Earth's crust, likely due to long-term subduction and crust thickening." The study links the LPC to the broader Trans-Himalayan arc system, which includes the Kohistan–Ladakh and Gangdese regions in the western Himalayas and Tibet. "This study connects the geological dots from the western to the eastern Himalayas," said Adlakha. "It confirms that subduction-related processes were not confined to Ladakh or Tibet but extended all the way to Arunachal Pradesh." The findings have broader implications, not just for understanding how the crust evolved in this region, but also for mineral exploration and seismic risk assessment in the northeast region, which remains one of India's most earthquake-prone areas. "This is just the beginning," said lead author Kunal Mukherjee. "There is much more to learn from the rocks of Arunachal and many more secrets waiting beneath the surface."
