Lok Sabha Question No. 2765 (UNSTARRED), answered on 2024-08-08
Subject: Impact of Glacial Lake Outburst Floods
Ministry: JAL SHAKTI
Asked by: Shri Shafi Parambil, Dr. Indra Hang Subba, Shri Sukhdeo Bhagat

2765.

## GOVERNMENT OF INDIA

## MINISTRY OF JAL SHAKTI DEPARTMENT OF WATER RESOURCES, RIVER DEVELOPMENT & GANGA REJUVENATION

## LOK SABHA

## UNSTARRED QUESTION NO.2765

ANSWERED ON 08.08.2024

## IMPACT OF GLACIAL LAKE OUTBURST FLOODS

SHRI SHAFI PARAMBIL SHRI SUKHDEO BHAGAT DR. INDRA HANG SUBBA

Will the Minister of JAL SHAKTI be pleased to state:

(a)  whether any studies have been commissioned to assess the impact of Glacial Lake Outburst Floods (GLOFs)  on  existing  and  proposed  Himalayan  infrastructure,  particularly  in  light  of  the  Teesta-III hydroelectric dam collapse in North Sikkim in October 2023, if so, the details thereof;

(b)  the  details  of  policy  changes  being  considered  to  strengthen  and  mitigate  the  risks  of  GLOFs  on infrastructure in vulnerable regions like Sikkim;

(c) whether there are plans to enhance monitoring and early warning systems for GLOFs in the Himalayan region and if so, the timeline for their implementation;

(d) whether the Ministry proposes to allocate funds for study and mitigation of risk posed by glacial lakes and if so, the details along with the current status of the National GLOF Mission; and

(e) the details of projects on study of glacial lakes and the risk posed by them supported by the Ministry till date?

## ANSWER

## THE MINISTER OF STATE FOR JAL SHAKTI

## ( SHRI RAJ BHUSHAN CHOUDHARY )

(a)  &  (b) Subsequent  to  Teesta-III  Hydroelectric  dam  collapse  in  October,  2023,  Central  Water Commission  has  decided  to  review  the  design  flood  of  all  the  existing  and  under  construction  dams vulnerable  to  Glacial  Lake  Outburst  Floods  (GLOFs)  to  ensure  their  adequate  spillway  capacity  for  a combination of Probable Maximum Flood/Standard Probable Flood and GLOF. Further, GLOF Studies has been made mandatory for all new dams planned having Glacial Lakes in their catchments.

(c) & (d) CWC monitors 902 Glacial Lakes and Water Bodies (including 477 Glacial Lakes & Water Bodies, having water spread area greater than 50 ha and 425 Glacial Lakes having size 10 ha to 50 ha) during the period from June to October every year. This enables the detection of relative change in water spread  area  of  Glacial  Lakes  &  Water  Bodies,  as  well  as  identifying  the  one's  which  have  expanded substantially during the monitoring month, from disaster perspective. The monthly monitoring reports can be accessed at https://cwc.gov.in/glacial-lakeswater-bodies-himalayan-region.

A Committee on Disaster Risk Reduction (CoDRR) under NDMA involving representatives from six Himalayan States/UTs and other stakeholders, has identified a set of high risk glacial lakes for sending expeditions  to  directly  assess  these  lakes  and  prepare  comprehensive  mitigation  strategies  in  terms  of setting up early warning system/other structural and non-structural measures.

A High Level Committee Chaired by Union Home Minister has approved a GLOF risk mitigation project for Rs 150 crores for the States of Himachal Pradesh, Uttarakhand, Sikkim and Arunachal Pradesh to support the efforts of State Governments to take up various mitigation measures related to GLOF.

(e) As per the information compiled by NDSA, 47 dams (38 Commissioned and 9 under construction dams) have been identified by Central Electricity Authority under Ministry of Power, which are likely to be affected by Glacial Lake Outburst Flood (GLOF) from the Glacial lakes in the Indian territory. GLOF studies have been completed for 31 projects.

The Ministry of Earth Science through its autonomous institute, the National Centre of Polar and Ocean Research (NCPOR), has been monitoring and carrying out scientific research on two pro-glacial lakes in the Chandra Basin, since 2013.

In a National Mission on Himalayan Studies (NMHS) sponsored study entitled "Snow and Glacier Contribution and Impact of Climate Change in Teesta River Basin, Eastern Himalaya", status of glacial lakes in Sikkim Himalayas has been prepared by National Institute of Hydrology, Roorkee.

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