In this guide
On the afternoon of 15 January 1934, a massive earthquake struck the Bihar–Nepal region. Towns such as Munger, Darbhanga, Motihari and Sitamarhi were devastated; the ground cracked open, sand and water spouted from fissures, and thousands died. Seventy-four years later, in 2008, the Kosi broke its embankment and drowned large parts of north-east Bihar. Between these events lie countless floods, droughts, heatwaves and lightning strikes. Bihar is one of India's most multi-hazard states.
Hazard profile
| Hazard | Where | Why |
|---|---|---|
| Floods | North Bihar especially (Kosi, Gandak, Bagmati, Kamla, Mahananda basins) | Himalayan rivers, heavy rain in Nepal, flat land, silt, embankments |
| Earthquakes | North Bihar in seismic zones IV and V | Proximity to the Himalayan collision zone |
| Drought | South and south-west Bihar | Lower rainfall, seasonal rivers |
| Heatwaves | Mainly south Bihar (Gaya, Aurangabad, Nawada) | Hot dry winds in May–June |
| Cold waves and fog | Across the plains | Winter |
| Lightning | Statewide, especially in the pre-monsoon and monsoon | Convective storms; many people working in open fields |
| Fire | Villages, especially in the dry season | Thatched houses, strong winds |
| Boat accidents | Rivers during floods and festivals | Overloaded boats |
Floods
- A large share of Bihar's area is flood-prone — commonly cited at about 73 per cent of its geographical area — and north Bihar is among the most flood-affected regions in India.
- Floods occur almost every year; some years (1987, 2004, 2007, 2008, 2017, 2019) have been especially severe.
- Causes: heavy rain in the Nepal catchment, sediment, flat terrain, embankment breaches, poor drainage and encroachment on floodplains.
- The 2008 Kosi breach is the most famous recent disaster — see our guide on the Kosi.
Earthquakes
| Earthquake | Date | Notes |
|---|---|---|
| Bihar–Nepal earthquake | 15 January 1934 | Magnitude about 8; widespread destruction in north Bihar (Munger, Darbhanga, Motihari, Sitamarhi) and Nepal; major liquefaction (sand boils) |
| Bihar–Nepal earthquake | 21 August 1988 | Epicentre in eastern Nepal; damage in Darbhanga, Madhubani and nearby districts |
| Nepal (Gorkha) earthquake | 25 April 2015 | Epicentre in Nepal; deaths and damage in north Bihar |
The 1934 earthquake led to a famous exchange: Gandhi described it as divine punishment for untouchability, and Rabindranath Tagore publicly disagreed, insisting natural disasters have physical, not moral, causes — an exchange sometimes cited in Ethics answers.
Drought
- South and south-west Bihar (Gaya, Aurangabad, Nawada, Jamui, Banka) face frequent drought.
- Even north Bihar can face deficient rainfall in some years — Bihar sometimes faces flood and drought in the same season.
- The traditional ahar–pyne system helped south Bihar manage scarce water.
Heatwaves and cold waves
- In June 2019, a severe heatwave caused many deaths in Gaya, Aurangabad and Nawada; authorities imposed restrictions under Section 144 on outdoor activities.
- Cold waves in December–January affect the elderly, the homeless and crops.
Lightning
- Bihar records among the highest numbers of lightning deaths in India every year.
- Victims are often farmers and labourers in open fields, or people sheltering under trees.
- Measures: early warning (including a state app, Indravajra), SMS alerts, awareness ("30-30 rule": seek shelter if thunder follows lightning within 30 seconds; stay inside for 30 minutes after the last thunder), and lightning arresters on buildings.
Institutions and plans
- Bihar State Disaster Management Authority (BSDMA), chaired by the Chief Minister, under the Disaster Management Act, 2005.
- Disaster Management Department of the state government.
- State Disaster Response Force (SDRF) and NDRF battalion (based at Bihta).
- District Disaster Management Authorities chaired by the District Magistrate.
- Bihar adopted a Disaster Risk Reduction Roadmap (2015–2030), aligned with the Sendai Framework.
- Standard operating procedures for flood preparedness, including pre-positioning boats, food packets and medicines, and community kitchens in relief camps.
Lessons and way forward
| Lesson | Measure |
|---|---|
| Floods cannot be fully controlled | Flood management — early warning, raised platforms, flood-resilient housing, insurance |
| Embankments can fail | Monitoring and maintenance; alternatives to more embankments |
| Earthquake risk is high | Enforce building codes; retrofit schools and hospitals |
| Lightning deaths are preventable | Warnings, awareness, shelters |
| Heatwaves are increasing | Heat action plans |
| Cooperation with Nepal is essential | Data sharing, joint projects |
Practice
Prelims-style:
- When did the great Bihar–Nepal earthquake occur?
- What share of Bihar's area is commonly cited as flood-prone?
- Who chairs the BSDMA?
- Where is the NDRF battalion in Bihar based?
- What is the Indravajra app?
Mains-style:
- "Bihar faces floods and droughts in the same year." Explain and suggest strategies.
- Examine the causes of high lightning deaths in Bihar and suggest remedies.
A note on dates and numbers. Exam patterns, vacancies and schedules change from year to year. Always confirm the current details in the latest notification on the Bihar Public Service Commission website .
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