Bihar Flood

• •Syllabus: Natural disaster & Floods*

Source: TH

Context: Bihar, India, is severely affected by annual floods, with millions displaced and livelihoods disrupted. The region’s geographic vulnerability, coupled with ineffective flood control measures, continues to exacerbate the problem.

Geographic Conditions Contributing to Flooding in Bihar:

• Proximity to the Himalayas: North Bihar is located downstream from Nepal, with rivers originating from the Himalayas flowing into Bihar.

• These rivers, including Kosi, Gandak, and Bagmati, carry large amounts of sediment, making the state flood-prone.

• River sedimentation: The young Himalayan rivers are sediment-heavy due to loose soil, causing them to overflow when rainwater increases the volume.

• Flat terrain: Bihar’s flat plains make it difficult for floodwaters to drain quickly, leading to prolonged waterlogging, especially during the monsoon.

• Permanent waterlogged areas: Low-lying areas, known as Chaurs, further complicate drainage, causing long-term waterlogging in certain regions.

• Impact of embankments: Embankments built along rivers like the Kosi have narrowed their channels, leading to sediment buildup and shallower riverbeds, increasing the risk of overflow.

Causes of Flooding in Bihar:

• Heavy rainfall in Nepal: Flash floods are often triggered by heavy rainfall in the Himalayan regions of Nepal, which drains into Bihar’s rivers.

• Overflowing rivers: During monsoons, snow-fed and rain-fed rivers breach their banks, flooding large areas.

• Embankment failures: Structural issues with embankments have led to breaches, worsening flood damage.

• Waterlogging from small rivers: Encroachment on drainage channels and silted rivers cause further water stagnation.

• Release of water from barrages: The release of water from Nepal’s barrages, such as the Kosi barrage, contributes to increased water levels.

Way ahead to handle floods:

• Integrated Flood Management: Building additional barrages, dams, and improving embankments must be accompanied by policies for early warnings and quick responses.

• Collaboration with Nepal: The long-pending proposal to build a dam on the Kosi requires diplomatic collaboration with Nepal to address upstream water management.

• Strengthening embankments: Regular maintenance and modernization of embankments, along with widening river channels to manage sediment, can mitigate flood impacts.

• Non-structural solutions: Improved flood forecasting, risk reduction policies, disaster management training, and community awareness programs are essential for flood preparedness.

• Rehabilitation of affected populations: Providing sustainable resettlement options for communities trapped within flood-prone embankments can prevent annual displacement.

Best Practice:

• Chennai: Stormwater Drainage System Chennai has enhanced its stormwater drainage system post-2015 floods by redesigning and expanding it. The city increased the number of stormwater drains and connected them to natural water bodies for efficient water flow and drainage during heavy rainfall.

• Surat: Flood Early Warning System (FEWS) Surat, a flood-prone city, uses a Flood Early Warning System (FEWS) to predict and monitor floods, especially in the Tapi River basin. This system allows for timely evacuations and preparation, minimizing flood damage.

Insta Links:

• Flood-Management-in-India

• Climate change and Flood

1. 1.The interlinking of rivers can provide viable solutions to the multi-dimensional inter-related problems of droughts, floods, and interrupted navigation. Critically examine. (UPSC – 2020)

1. 1.Account for the huge flooding of million cities in India including the smart ones like Hyderabad and Pune. Suggest lasting remedial measures. (UPSC – 2020)