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Glacial Lake is born and it will Die (Glacial Outburst) - Ritesh Arya with Dinesh Sati on Hemkunt Lake

  • An example of glaciated lake Gurudwara Hemkunt Sahib (15000 ft) and how it can pose a threat to the Gurudwara Gobind Dham (10000 ft) downstream in case of glacial lake outburst


  • A clear view of Gurudwara Hemkunt Sahib (15000 ft) and Gurudwara Gobind Dham (10000 ft) in a single view. (NBM Photo)
    An example of glaciated lake Gurudwara Hemkunt Sahib (15000 ft) and how it can pose a threat to the Gurudwara Gobind Dham (10000 ft) downstream in case of glacial lake outburst
    Kamana Misra, Ritu Arya Sharma and 40 others
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    • Dinesh Sati I am sorry but the area has no pre-conditions for any glacial lake outburst at the place! I don't know what evidences you collected to making such a comment! I am asking my glaciologist friends from WadiaInstitute specially DP Dobhal and Manish Mehta to clarify if there is any GLOF condition at Hemkund sahib!
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      • Manish Mehta Dinesh Sati you are right sir. It is not a moraine dammed lake nor a lake made of ice. It is a Cirque glacial lake and formed due to scouring or excavation, hard rock by the glacier. The embankment of the lake is formed by hard and compact rock rock. So this lake cannot break until a big earthquake hits. this lake is stronger than Tehri Dam
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    • Manish Mehta Dinesh Sati Sir, you are right sir. It is not a moraine dammed lake nor a lake made of ice. It is a Cirque glacial lake and formed due to scouring or excavation, hard rock by the glacier. The embankment of the lake is formed by hard and compact rock rock. So this lake cannot break until a big earthquake hits. this lake is stronger than Tehri Dam
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    • Ritesh Arya this is a glacier-fed lake hence it is a glacier lake .....and highly prone to landslides ..a major slide can trigger a huge splash which can create a glacial lake outburst... and secondly earthquake can definitely trigger the same that was my point.... This is a general observation applicable to any glacial lake found in the Himalayas ..... Though moraine damn lakes behave slightly different ....but the cirque glacial lakes which form by finding its way through the hard rock ....after some point of time the wall which holds the water in the lake erodes these rocks which become weak and gradually burst unable too withstand the hydrostatic pressure created by the water .... This is the dynamic behavior of these lakes ...
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    • Manish Mehta Now, this is not glacial fed..this is snow and avalanche fed lake... You think right..but I am not agree with you...first the lake formed over the high grade metamorphic, central crystalline rock...not a sedimentary rock...the front where you think the lake could break or erode is almost 500 m wide...it is amphitheater like structure and till date there is no evidence of broken corque lake in the world ... and this is formed over high grade crystalline rock...only moraine dammed lake is dangerous
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    • Parneet Singh Sir .... The lake formed there is of cirque type n it requires extreme seismic activity for the lake outburst to occur.... N secondly the rock type where the lake is ..of highly metamorphosed type so second reason which states that outburst is unlikely…See more
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    • Ritesh Arya What is avalanche fed lake...... I think avalanche is good enough reason to give it an outburst. Outburst is inevitable, its only a matter of geological time if the glacier and glacial melt can form A cirque which is an amphitheater-like valley formed by glacial erosion. So the lake formed by glacial origin it has to be a glacial lake.
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      • Dinesh Sati Dear Ritesh with a very small catchment (indicated by red dotted line on Google earth image) that too without any glacier coming down to the lake, I don't know how you visualize an avalanche that may hit the lake and produce an outburst condition. I fully agree with the points made by Manish and Parneet! As there is insignificant influx of debris the small conical hills on the toe of sub-vertical bedrock (on the rim of the lake) have turned stable because of saturation and therefore I don't see any slope movement!
        No photo description available.
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      • Ritesh Arya Dinesh Sati Manish said it was an avalanch fed lake not me

        And dear Sati ji
        I don't know how you calculate with surity the stability because of saturation and there you conclude no slope movement because I find these eroded weathered hills highly fragile and would not recommend a good site for sustainable habitation
        And if we have to still keep the habitation proper monitoring of these slides should be done because the glaciers are on the verge of extinction here and the debris will have to move down we cannot stop but it is being prolonged। I agree
        No body can predict the timing of movement but nobody can either deny it
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      • Dinesh Sati Ritesh Arya I don't know if you have visited the site and thereafter synthesizing your observations or making general comments based on available topography! I agree with you that habitations should not be settled around zones of known instability as we have witnessed many flashfloods events in This part specially where thickness of debris along drains remained very high. In 2013 during Kedarnath flashflood the lower reaches of this valley also got inundated. But coming up to this location, the site conditions are quite different. You have almost unweathered rock mass projecting on the surface as dictated by rock defects (where did you notice eroded weathered hills, plz specify the locations?). Like many environmentalists, those understand very little about this science, it's un- solicited from a geologist like you to grade the Himalayan rocks into "fragile"! If you have any standard fragility scale where geotechnical number for each rock is given, then plz pass on to me or this discussion group, so that it would be beneficial to the practicing geologists/ geotechnical experts. One must not forget that there are so many major engineering projects/structures have been constructed and upcoming too on the same very "fragile" rocks and till date there is no major mishap reported. Anyways, the bedrock structural and geotechnical parameters do not suggest any possibility of rockslope movement in near future. Secondly, as already conveyed in my comments the thickness, site conditions of the debris/soilslopes is not critical and hence I don't see any possibility of slope movement either.
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      • Ritesh Arya My observations are based on the picture. This picture shows the accumulated debris in the hills above the lake. may look irrelevant or insignificant but they have the potential to create lot of devastation when it moves. I have studied these effects in Leh floods in 2010. where these insignificant deposits at the top of the hills when they move with great velocity can change the entire geomorphology of the entire region within seconds. 7-10 feet of debris accumulation in few seconds between Sabo and Choglamsar
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      • Dinesh Sati Dear Ritesh, that's wrongly plotted there! I am sure that you haven't visited the place and that's why you are confusing with the actual location and the wrong marking done on Google earth. Plz don't jump on conclusions that too of the sensitive nature without actually knowing the facts!!
      • Dinesh Sati Ritesh again, there is no correlation between Leh where monsoon clouds don't even enter with monsoon covered Lesser or Higher Himalayan areas!! There is nothing common!
      • Ritesh Arya I think the location of the lake is clearly marked in the picture and I am not jumping into any conclusion This is a general observation of any lake in the Himalayas that a glacial lake is borne and there will be a death of that lake which we call lake outburst...So the life of the lake and its death is inevitable so this is a general conclusion if you think otherwise ...
      • Ritesh Arya Dinesh Sati I will be happy if you can share a complete picture if you have one with the glacier and its debris at the top..
      • Ritesh Arya Dinesh Sati You have mentioned that there is no major mishap reported till now ...this does not guarantee that the flooding or mishap will not occur in near future... you have also mentioned that the bedrock structural and geotechnical parameters do not suggest any possibility of rock slope movement in near future. and you also said that the thickness, site conditions of the debris/soil slopes are not critical and hence you don't see any possibility of slope movement either.
        As a geologist, I think this statement is a very bold statement and the authorities in Hemkunt sahib should relax and not prepare for any natural calamity in the future.
        ....but that is not the case, your statements are bold but very unrealistic for 2 reasons it does not guarantee the time till this slopes will remain stable secondly if you give no time then there is no meaning in your statement because you mean to say it will never happen or are you saying the slopes are stable now but you don't know when they will become unstable and then what will be the consequences you don't know ..this is not the way geologist is supposed to understand I think we know that the mishap will happen for sure and if we can prepare the concerned authorities with the future impact this debris would cause then the authorities can also take necessary precautions and react accordingly in case of any eventuality and are not taken by surprise as we saw in the Leh and Kedarnath floods. Nobody could ever imagine the Ladakh batholiths granite being so compact and hard would crumble on midnight of 5th August 2010 by unprecedented rains ...The lightening in the sky in Leh still give shocks to the people who survived that night. The event may happen in 10, 100 or 200 years or maybe 500 years but will happen and we at present really don't know when that D day actually is .. But the authorities in Hemkunt should be prepared always and monitor these perpetual threats to avert the dangers associated with it in the near future.
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    • Manish Mehta See the sketch sir
      No photo description available.
    • Ritesh Arya Manish both are glacial fed lakes and both are formed by the action of glacier
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    • Ritesh Arya One we call Cirque and the other moraine lake
    • Ritesh Arya I think if you have seen Lamayuru lake it was mixture of both the processes
    • Ritesh Arya But that too ruptured
    • Manish Mehta Sir you are little confused Lamayuru was not glacial lake this was landslide blockade lake sir..it formed due to huge land slide in both side of bottle neck narrow valley, that's why its breached due to vertical column of water pressure change towards horizontal pressure due to seepage of water....but in hemkund sahib no seepage has been observed only surface flow is there
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      • Manish Ji Lamayuru was a Glacial lake ..... What do you mean by Landslide blockade lake... There was no landslide in Lamayuru ....if you have evidence please show
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      • Ritesh Arya You mean Paleolandslide deposits ....i have worked in Lamayuru for months I was not able to get anyevidence
      • Manish Mehta Ritesh Arya sir, I am not telling..study said
        Lamayuru basin at an altitude of 3600 m in western Ladakh appears to be a possible source of palaeo-climatic information was created by neotectonic instability around 35–40 ka. Developed in the main valley         along the Indus Suture Zone in the Trans Himalaya, the basin consists of fluvio-lacustrine deposits ranging in age from late Pleistocene to Holocene. The palaeolake was formed when the River Lamayuru was dammed by a heavy land-slide (De Terra & Paterson, 1939; Fort, Burbank & Freytet, 1989).
      • Ritesh Arya Manish Mehta the report say possible....they are not sure please don't quote reports who are not sure....
      Manish Mehta Lanslide you will always get assorted deposits of debris consisting of huge boulders pebbles sand, clay but Lamayuyu is very well sorted ....no question of landslide
    • Sumit Sagar Dogra I credible pic👌
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