Flash Flood Vulnerability in India

Relevance: GS III – Disaster Management

India is more susceptible to flash floods—sudden, severe flooding events that cause extensive damage in a matter of minutes—because of its varied topography and climate zones. Extreme rainfall, cloudbursts, and glacial lake outbursts are the main causes of flash floods, which have increased in frequency as a result of deforestation, unplanned urbanization, and climate change. High-risk areas have been identified in areas like the Western Ghats, the Himalayan belt, and portions of Central India. Building climate resilience and safeguarding vulnerable communities in India requires an understanding of the causes, geographic patterns, disaster management techniques, and the function of early warning systems as the country struggles with the growing threat.

Key Findings

The Brahmaputra, Narmada, Tapi, Mahanadi, Brahmani, and West Coast River basins are sub-basins that are particularly vulnerable to flash floods.

• Additionally, portions of the Godavari, Ganga, Mahi, and Indus River basins exhibit high flash flood risk.

Flash Floods: What Are They?

A flash flood is defined as a short-duration flood with a reasonably high peak discharge when there is less than four to six hours between the observable causal event and the flood (WMO, 2006).

• The number of flash flood episodes rose from 132 to 184 between 2020 and 2022 (Jal Shakti Ministry). Over 5,000 people lose their lives to flash floods each year.

Flash Flood Guidance System (FFGS)

An Instrument for Risk Mitigation and Early Warning. Flash flood dangers are alerted six to twenty-four hours in advance via the real-time early warning system oFFGS.

• As part of a regional initiative for South Asian nations, including Bangladesh, Sri Lanka, Nepal, Bhutan, and India, it has been in operation since 2020. Offers high-resolution forecasts with a spatial coverage of 4 km by 4 km.
• Works at the watershed level, emphasizing urban flash flood zones and the Himalayan region.

Important Causes of Flash Floods

25% Flash floods usually happen six hours after intense rain, which is frequently brought on by cloudbursts. For instance, the Himalayan areas.

• In mountainous areas, steep terrain and narrow river channels promote quick water buildup and downstream surge.
• Sudden release of dams, embankments, or check dams as a result of pressure buildup from upstream rains; Water does not percolate and causes abrupt surface runoff.

Mains: 

Question: Flash floods are a growing concern for India’s disaster resilience framework. Examine the geo-climatic and anthropogenic causes behind their increasing frequency. (250 words)

Note: To take UPSC mains tests on GS Mains Q & A, click the link that is attached.

Mains PYQs: 

Question: Differentiate the causes of landslides in the Himalayan region and Western Ghats. (UPSC IAS 2021)

MCQs:

Note: To take practice tests on Daily current Affairs MCQs, click the link that is attached.

Question: With reference to flash floods in India, consider the following statements:

1. Flash floods usually occur more than 12 hours after heavy rainfall.
2. The Flash Flood Guidance System (FFGS) operates at the watershed level.
3. Flash floods are commonly observed in flat terrain with wide river channels.

Which of the statements given above is/are correct?

1. a) 1 and 2 only
2. b) 2 only
3. c) 1 and 3 only
4. d) 2 and 3 only

Answer: b) 2 only

UPSC Exam 2025 Related Articles

UPSC General Studies Paper Preparation