On 3 September 2026 the Union Home Secretary, Shri Govind Mohan, reviewed the preparedness of the Himalayan States and Union Territories against Glacial Lake Outburst Floods and snow avalanches. Present were the Chief Secretaries and State Disaster Management Authorities of Uttarakhand, Himachal Pradesh, Sikkim, Arunachal Pradesh and Jammu & Kashmir, with the NDMA, the Central Water Commission, the India Meteorological Department and the Defence Geoinformatics Research Establishment.
The direction given was that preparedness must move beyond response towards risk-informed planning, preventive mitigation and community-level preparedness, and that States should expedite the GLOF mitigation project sanctioned by the Centre in 2024.
The meeting is routine. The hazard is not, and its mechanism is the part an examiner will test.
What a GLOF is, mechanically
As a glacier retreats, meltwater collects in the hollow it leaves behind, dammed by the ridge of rock debris the glacier pushed up — a moraine — or by residual ice. The result is a glacial lake: a body of water held back by a wall that was never engineered.
A Glacial Lake Outburst Flood occurs when that dam fails, releasing the lake in hours or minutes. The triggers are few and worth listing:
- A rock or ice avalanche falling into the lake, sending a wave over the dam — the commonest trigger.
- Piping — seepage through a moraine that gradually erodes an internal channel until the dam collapses.
- Earthquake shaking a loosely consolidated moraine.
- Rapid melt or heavy rain raising the lake above the dam crest.
The defining feature, and the reason the hazard is so lethal, is speed against distance. A monsoon flood rises over days; a GLOF arrives as a wall of water and debris that can travel tens of kilometres downstream faster than a warning can propagate by conventional means. That is why the meeting's vocabulary was flow path, early warning, last-mile dissemination — the whole problem is the interval between dam failure and the first village.
The precedent every answer should cite
On 4 October 2023, the South Lhonak Lake in North Sikkim breached. The flood ran down the Teesta, destroyed the Teesta-III (Chungthang) hydroelectric dam, and killed people well downstream. It is the reference case for three reasons: the lake had been identified as high-risk for years; the trigger was consistent with a slope failure into the lake; and the damage fell heavily on infrastructure built in the flow path.
The earlier reference is Kedarnath, June 2013, where the Chorabari lake above the shrine breached after extreme rainfall — a GLOF compounding a cloudburst. Together the two cases explain why hydropower siting and pilgrimage infrastructure recur in any discussion of Himalayan risk.
Snow avalanches are a related but distinct hazard. The Chamoli disaster of February 2021 began as a rock-and-ice avalanche off a high peak into the Rishiganga valley, which then behaved like a flood — a useful reminder that in the Himalaya, the categories bleed into each other.
Who does what
The institutional map is a standard match-the-pairs, and the meeting's attendance list is that map.
| Body | Role | Parent |
|---|---|---|
| NDMA | Apex disaster-management policy body; chaired by the Prime Minister | Statutory under the Disaster Management Act, 2005 |
| SDMA / DDMA | State and district authorities; chaired by the Chief Minister and the District Collector respectively | Same Act |
| NDRF | Specialist response force | Under the NDMA's general superintendence |
| CWC | Hydrological monitoring, flood forecasting, dam safety | Ministry of Jal Shakti |
| IMD | Weather forecasting and warnings | Ministry of Earth Sciences |
| DGRE | Avalanche forecasting and snow-hazard research; formerly the Snow and Avalanche Study Establishment (SASE) | DRDO |
Two points from the table repay attention. The Ministry of Home Affairs is the nodal ministry for disaster management, which is why the Home Secretary convened the review — but it does not chair the NDMA; the Prime Minister does. And the avalanche specialist is a defence laboratory, because the Army has spent decades on snow-bound frontiers and built the expertise there; DGRE's warnings serve civil authorities too.
The 2005 Act was amended in 2025, among other things to provide for Urban Disaster Management Authorities in State capitals and large cities and to give statutory backing to State Disaster Response Forces — the same shift toward pre-positioned, local capacity that the review demanded.
What "risk-informed" means in practice
The instruction to move from response to risk-informed planning has concrete content, and it is worth being able to spell it out.
Mapping. Under the National Glacial Lake Outburst Flood Risk Mitigation Programme sanctioned in 2024, close to two hundred glacial lakes across the four Himalayan States were identified as high-risk. Mapping converts a diffuse hazard into a list.
Monitoring. Satellite imagery tracks lake area over time; a lake that is growing is a lake to watch. Automatic weather stations and water-level sensors at the lake give the earliest signal.
Mitigation. The proven engineering intervention is controlled lowering of the lake — siphoning or cutting a channel to reduce the volume behind the dam so that, if it fails, less water is released. Sikkim has done this at some lakes; Nepal did it at Tsho Rolpa decades ago.
Warning and evacuation. Sensors upstream, sirens downstream, and pre-agreed evacuation routes — with the flow path modelled in advance so that everyone knows which villages are in it.
The intellectual shift is from "how fast can we reach the survivors" to "how do we ensure there are no people in the flow path when it fails." Stated that way, it is the entire difference between disaster response and disaster risk reduction, and it is the sentence to use in an answer.
🔑 Revision block
- 3 September 2026: Home Secretary Govind Mohan reviewed GLOF and avalanche preparedness with Uttarakhand, Himachal Pradesh, Sikkim, Arunachal Pradesh, J&K, plus NDMA, CWC, IMD, DGRE.
- GLOF = failure of a moraine or ice dam holding a glacial lake; triggers — avalanche into the lake, piping, earthquake, rapid melt/rain.
- Precedents: South Lhonak Lake, Sikkim, 4 October 2023 (Teesta-III dam destroyed); Kedarnath, June 2013 (Chorabari lake); Chamoli, February 2021 (rock-ice avalanche).
- NDMA chaired by the Prime Minister; SDMA by the CM; DDMA by the Collector — all under the Disaster Management Act, 2005, amended 2025 (Urban DMAs, statutory SDRFs).
- MHA is the nodal ministry but does not chair the NDMA.
- CWC → Jal Shakti; IMD → Earth Sciences; DGRE → DRDO (formerly SASE).
- National GLOF Risk Mitigation Programme, 2024: close to 200 high-risk lakes in four States.
- Mitigation = map, monitor, lower the lake, warn along the flow path. Risk reduction means no one in the flow path, not faster rescue.
🎯 Practice MCQs
Q1. A glacial lake outburst flood results from the failure of a: (a) concrete dam (b) moraine or ice dam (c) river embankment (d) canal head-works → (b).
Q2. The South Lhonak Lake GLOF of October 2023 occurred in: (a) Uttarakhand (b) Himachal Pradesh (c) Sikkim (d) Arunachal Pradesh → (c), on the Teesta.
Q3. The National Disaster Management Authority is chaired by the: (a) Union Home Minister (b) Prime Minister (c) Cabinet Secretary (d) President → (b).
Q4. DGRE, which forecasts avalanches, functions under: (a) IMD (b) NDMA (c) DRDO (d) the Ministry of Home Affairs → (c) — formerly SASE.
Q5. The Central Water Commission is attached to the: (a) Ministry of Earth Sciences (b) Ministry of Jal Shakti (c) Ministry of Home Affairs (d) NITI Aayog → (b).
Q6. Which of the following did not attend the 3 September 2026 review, per the release? (a) Sikkim (b) Uttarakhand (c) Ladakh (d) Arunachal Pradesh → (c).
Q7. The commonest trigger of a GLOF is: (a) drought (b) an avalanche or slope failure into the lake (c) dam construction (d) river capture → (b).
Q8. The Kedarnath disaster of 2013 involved the breach of: (a) Gaumukh (b) Chorabari lake (c) Roopkund (d) Satopanth → (b).
Q9. The Disaster Management Act was enacted in: (a) 2001 (b) 2004 (c) 2005 (d) 2008 → (c).
Q10. The proven engineering mitigation for a dangerous glacial lake is: (a) building a concrete dam across it (b) controlled lowering of the lake level (c) diverting the glacier (d) afforesting the moraine → (b).
Q11. Consider the following: 1. The Ministry of Home Affairs is the nodal ministry for disaster management. 2. The Union Home Minister chairs the NDMA. (a) 1 only (b) 2 only (c) Both (d) Neither → (a).
Q12. The Chamoli disaster of February 2021 began as a: (a) cloudburst (b) earthquake (c) rock-and-ice avalanche (d) dam breach → (c), into the Rishiganga valley.
📋 How this gets asked (PYQ pattern)
Disaster-management questions run in four shapes. The chair item — who heads the NDMA, SDMA and DDMA, with the Home Minister as the standard wrong option. The agency item — matching CWC, IMD, DGRE and NDRF to their parent ministries. The mechanism item — what a GLOF, a cloudburst or an avalanche actually is, asked as a definition. The case item — the year and State of a named disaster.
The fresh 2026 hook is the five-State review and the 2024 mitigation programme, likeliest to appear as a which-State or which-agency identification. A statement pair on the NDMA's chair and the nodal ministry is the most probable two-statement item, with the chair half planted false. As always, we describe the recurring pattern, not any exact past question.
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✍️ Written by Aditya Tiwari — Geography & governance faculty at The Cavalier. Reviewed by the Cavalier Faculty Desk. The Cavalier, founded by ex-Army officers, has trained NDA/CDS/SSB aspirants since 2001 (Facebook · YouTube).
Source: PIB / Ministry of Home Affairs, 3 September 2026. Hazard mechanics and institutional details cross-verified with independent sources.