Syllabus: GS –III & V: Disaster Management, Environment & Ecology

Why in the News?

Upper Assam, particularly Sivasagar, Charaideo and neighbouring districts, recently witnessed one of the most severe floods in recent decades. Record water levels in the Disang, Dikhow and Jhanji rivers exposed the growing impact of climate variability, environmental degradation and inadequate disaster preparedness.

Why Did the Flood Become So Severe?

The disaster resulted from the combined effect of natural and human-made factors.

• Heavy Rainfall in the Upper Catchment: Heavy rainfall in Mon and Mokokchung districts of Nagaland saturated the entire catchment.
  • The Disang, Dikhow and Jhanji rivers originate in the hills of Nagaland and Arunachal Pradesh before entering Assam.
  • Since the soil was already saturated, almost the entire rainfall became surface runoff, rapidly raising river levels.
• Environmental Degradation: Large-scale legal and illegal mining in the Naga Hills accelerated soil erosion.
  • Deforestation reduced the hills’ ability to absorb rainwater.
  • Sediments from mining and erosion accumulated in riverbeds, reducing their carrying capacity.
• Unplanned Infrastructure Development: Roads and highways were constructed without adequate hydrological assessments.
  • Poorly designed culverts and drainage systems blocked the natural flow of floodwater, creating artificial waterlogging in nearby settlements.
  • Wetlands and traditional water bodies were encroached upon for urban expansion and brick kilns, reducing natural flood storage capacity.

Major Challenges During the Flood

The disaster exposed several gaps in flood management.

• Relief distribution remained uneven, with remote villages receiving delayed assistance.
• Limited availability of boats and rescue equipment slowed evacuation efforts.
• Stagnant water, dead livestock and poor sanitation increased the risk of water-borne and vector-borne diseases such as diarrhoea, malaria, dengue and Japanese Encephalitis.
• The absence of a real-time coordination platform reduced the efficiency of government agencies and voluntary organisations.

Why is Assam Highly Vulnerable to Floods?

Several geographical factors increase flood risk.

• The Brahmaputra basin receives one of the highest rainfalls in the world.
• Young Himalayan rivers carry enormous quantities of sediment, causing riverbeds to rise over time.
• Frequent earthquakes alter river courses and increase erosion.
• Climate change is increasing the frequency of extreme rainfall events.
• Rapid urbanisation, deforestation and wetland loss further aggravate flooding.

What Needs to be Done?

• Adopt River Basin Management: Flood management should be planned for the entire river basin rather than individual districts.
  • Assam, Nagaland and Arunachal Pradesh should establish a Joint River Basin Management Authority for coordinated planning.
• Strengthen Scientific Flood Monitoring: Use satellite imagery, drones and Geographic Information Systems for real-time flood mapping.
  • Develop integrated digital dashboards for better coordination among disaster management agencies.
• Restore Natural Ecosystems: Protect and restore wetlands (beels), floodplains and forests that naturally absorb floodwater.
  • Strictly regulate mining and promote afforestation in upstream catchments.
• Improve Infrastructure: Construct scientifically designed bridges, culverts and drainage systems based on hydrological studies.
  • Increase the capacity of river channels through selective desiltation where scientifically justified.
• Enhance Disaster Preparedness: Pre-position rescue boats, amphibious vehicles and emergency medical supplies in vulnerable districts.
  • Strengthen village-level disaster volunteers through the Aapda Mitra Scheme for community-based disaster response.

Government Initiatives

• National Disaster Management Act, 2005
• National Disaster Management Authority (NDMA)
• State Disaster Management Authority (SDMA)
• District Disaster Management Authority (DDMA)
• Aapda Mitra Scheme for training community disaster response volunteers.
• National Cyclone Risk Mitigation Project (best practices in disaster preparedness).
• National Mission for Sustainable Agriculture and Green India Mission, which indirectly support watershed conservation and ecosystem restoration.

Important Terms Explained

River Basin

A river basin is the entire geographical area from which all rainfall drains into a particular river and its tributaries.

Catchment Area

The catchment area is the land area that collects rainfall and channels it into rivers, streams and lakes.

Surface Runoff

Surface runoff is rainwater that flows over the ground instead of being absorbed into the soil.

Hydrological Study

A hydrological study examines rainfall, river flow, drainage and groundwater to design safe infrastructure and manage floods.

Biosecurity

Biosecurity refers to measures that protect people, ecosystems and livelihoods from biological and environmental hazards, including disease outbreaks following floods.

Nature-based Solutions

These are measures such as restoring wetlands, forests and floodplains to naturally reduce flood risks while conserving biodiversity.

Way Forward

Assam’s flood problem cannot be solved by embankments alone. Sustainable flood management requires scientific river basin planning, interstate cooperation, ecosystem restoration, climate-resilient infrastructure and community participation. A shift from reactive relief measures to proactive risk reduction will make Assam more resilient to future floods while protecting lives, livelihoods and the environment.

Exam Hook

Key Takeaways

• The recent Upper Assam floods were caused by a combination of intense rainfall, upstream environmental degradation and inadequate drainage infrastructure.
• The Disang, Dikhow and Jhanji rivers originate in Nagaland and Arunachal Pradesh, highlighting the need for interstate river basin management.
• Wetland conservation, afforestation and scientific infrastructure planning are essential for long-term flood mitigation.
• Technology such as drones, satellite mapping and Geographic Information Systems can improve disaster preparedness and response.
• Community participation through the Aapda Mitra Scheme is crucial for building local disaster resilience.

Question

“Recurring floods in Assam are increasingly becoming a consequence of both natural processes and human interventions.” Discuss the causes of recent floods in Upper Assam and suggest a sustainable river basin management strategy. (250 words)

One-line Wrap

The recent Upper Assam floods demonstrate that lasting flood resilience can only be achieved through integrated river basin management, ecological conservation, scientific planning and active community participation.