<p>A newly formed Himalayan lake raised fears Friday of another flash flood above a disaster-hit valley in northern India, prompting authorities to conduct helicopter surveys and send a team on a 16-hour climb to investigate.</p>.<p>Thirty-six people died and 168 are still missing after a barrage of water and debris hurtled down the valley in Uttarakhand with terrifying speed and force on Sunday, obliterating roads and bridges and smashing through dams.</p>.<p><strong>Read | <a href="https://www.deccanherald.com/national/uttarakhand-flash-floods-rising-river-waters-delay-rescue-efforts-950140.html">Uttarakhand flash floods: Rising river waters delay rescue efforts</a></strong></p>.<p>The flash flood on the Rishiganga river is thought have been triggered by a chunk of glacier breaking off, or a glacial lake -- formed when a glacier retreats -- bursting its banks.</p>.<p>Glaciers are receding fast in the region due to global warming.</p>.<p>On Thursday, geologists said that a new lake had formed near the same river.</p>.<p><a href="https://www.deccanherald.com/national/uttarakhand-flood-glacier-live-updates-deaths-missing-chamoli-rishikesh-haridwar-alert-trivendra-singh-rawat-alakananda-glacial-burst-ndrf-dhauli-ganga-joshimath-949868.html#1" target="_blank"><strong>Uttarakhand floods live updates on DH</strong></a></p>.<p>Professor YP Sundriyal of Hemwati Nandan Bahuguna Garhwal University released a video shot in the area, in which he pointed out the location of the lake and said, "this means that the Rishiganga will breach again".</p>.<p>Satellite images and a helicopter survey had confirmed the presence of the lake, senior local police official Ashok Kumar told AFP.</p>.<p>He said that teams had been sent to investigate on foot, a trek that would take around 16 hours, with the spot at around 4,200 metres (14,000 feet) above sea level.</p>.<p><strong>Read | <a href="https://www.deccanherald.com/national/north-and-central/uttarakhand-floods-drilling-operation-at-tapovan-tunnel-continues-families-get-impatient-949960.html" target="_blank">Uttarakhand floods: Drilling operation at Tapovan tunnel continues; families get impatient</a></strong></p>.<p>"But there is one important thing to note. For the last few days, there was less water flow in the Rishiganga. But since yesterday, the flow is a lot," Kumar said.</p>.<p>"That means that the lake has given some opening. It would have been dangerous if the water had just been collected and there was no flow."</p>.<p>A desperate and arduous search continued on Friday to reach around 30 people trapped in a tunnel since Sunday's flood, with hopes fading for their survival.</p>.<p><strong>Read | <a href="https://www.deccanherald.com/national/north-and-central/breach-of-sub-glacial-lake-may-have-caused-uttarakhand-floods-949802.html">Breach of sub-glacial lake may have caused Uttarakhand floods</a></strong></p>.<p>"We are trying to go to the smaller tunnel which is 12 metres below the existing one," Kumar said.</p>.<p>"In the small tunnel, we are hoping for the best... If they escaped the slush and the water, they might be safe in one corner."</p>
<p>A newly formed Himalayan lake raised fears Friday of another flash flood above a disaster-hit valley in northern India, prompting authorities to conduct helicopter surveys and send a team on a 16-hour climb to investigate.</p>.<p>Thirty-six people died and 168 are still missing after a barrage of water and debris hurtled down the valley in Uttarakhand with terrifying speed and force on Sunday, obliterating roads and bridges and smashing through dams.</p>.<p><strong>Read | <a href="https://www.deccanherald.com/national/uttarakhand-flash-floods-rising-river-waters-delay-rescue-efforts-950140.html">Uttarakhand flash floods: Rising river waters delay rescue efforts</a></strong></p>.<p>The flash flood on the Rishiganga river is thought have been triggered by a chunk of glacier breaking off, or a glacial lake -- formed when a glacier retreats -- bursting its banks.</p>.<p>Glaciers are receding fast in the region due to global warming.</p>.<p>On Thursday, geologists said that a new lake had formed near the same river.</p>.<p><a href="https://www.deccanherald.com/national/uttarakhand-flood-glacier-live-updates-deaths-missing-chamoli-rishikesh-haridwar-alert-trivendra-singh-rawat-alakananda-glacial-burst-ndrf-dhauli-ganga-joshimath-949868.html#1" target="_blank"><strong>Uttarakhand floods live updates on DH</strong></a></p>.<p>Professor YP Sundriyal of Hemwati Nandan Bahuguna Garhwal University released a video shot in the area, in which he pointed out the location of the lake and said, "this means that the Rishiganga will breach again".</p>.<p>Satellite images and a helicopter survey had confirmed the presence of the lake, senior local police official Ashok Kumar told AFP.</p>.<p>He said that teams had been sent to investigate on foot, a trek that would take around 16 hours, with the spot at around 4,200 metres (14,000 feet) above sea level.</p>.<p><strong>Read | <a href="https://www.deccanherald.com/national/north-and-central/uttarakhand-floods-drilling-operation-at-tapovan-tunnel-continues-families-get-impatient-949960.html" target="_blank">Uttarakhand floods: Drilling operation at Tapovan tunnel continues; families get impatient</a></strong></p>.<p>"But there is one important thing to note. For the last few days, there was less water flow in the Rishiganga. But since yesterday, the flow is a lot," Kumar said.</p>.<p>"That means that the lake has given some opening. It would have been dangerous if the water had just been collected and there was no flow."</p>.<p>A desperate and arduous search continued on Friday to reach around 30 people trapped in a tunnel since Sunday's flood, with hopes fading for their survival.</p>.<p><strong>Read | <a href="https://www.deccanherald.com/national/north-and-central/breach-of-sub-glacial-lake-may-have-caused-uttarakhand-floods-949802.html">Breach of sub-glacial lake may have caused Uttarakhand floods</a></strong></p>.<p>"We are trying to go to the smaller tunnel which is 12 metres below the existing one," Kumar said.</p>.<p>"In the small tunnel, we are hoping for the best... If they escaped the slush and the water, they might be safe in one corner."</p>