NDMA to monitor 189 high-risk glacial lakes to prevent disasters

Sub: Geo

Sec: Climatology

Context:

The National Disaster Management Authority (NDMA) has identified 189 high-risk glacial lakes in the Himalayas for targeted mitigation efforts.

Details:

Measures include investigating these lakes and implementing “lake-lowering measures” to prevent overflows and mitigate potential downstream damage.
The initiative follows disasters like the South Lhonak Lake overflow in Sikkim, which resulted in significant loss of life and infrastructure damage.
India has approximately 7,500 glacial lakes, some monitored via remote sensing, though full assessments require difficult site visits during limited accessible months (July-September).
The Central Water Commission (CWC) is monitoring 902 glacial lakes and water bodies via satellite.

Ongoing Efforts:

Arunachal Pradesh State Disaster Management Authority has dispatched teams to study six high-risk lakes in the Tawang and Dibang Valley districts.
The program includes technical hazard assessments, installation of Automated Weather and Water Level Monitoring Stations (AWWS), and Early Warning Systems (EWS).
So far, 15 expeditions have been completed across regions like Sikkim, Ladakh, Himachal Pradesh, and Jammu and Kashmir, with seven more expeditions ongoing.

National Glacial Lake Outburst Floods Risk Mitigation Programme (NGRMP):

The Indian government launched a ₹150 crore NGRMP to address the risks associated with glacial lakes in the Himalayan region.
The NGRMP action plan is likely to have four components:
- Component 1 will focus on Glof hazard and risk assessment. 15% of the programme budget will go towards creating and updating a glacial lake inventory and its classification in terms of hazard, vulnerability and risk assessment.
- Component 2 will focus on ‘Glof monitoring and early warning system. 35% of the allocation will go towards remote sensing techniques, advanced seismometers, water level sensors, cameras and trigger lines to monitor risk-prone lakes and the designing of a warning system backed with smartphones and sirens downstream to prevent loss of life and property.
- Component 3 will focus on Glof mitigation measures. It will have a maximum outlay of 40% of the budget and will look at site-specific interventions such as reinforcing unsafe moraine dams at glacial lakes, draining of lake waters through siphoning, controlled blasting, and excavation of artificial drainage channels.
- The fourth component will be dedicated to awareness generation and community-centric capacity building involving multiple stakeholders. The idea will be to prepare contingency plans. This component will also encourage more R&D on the phenomenon of glacial recession and Glof.

Source: TH