Nature Disaster: Coping with Floods, Droughts, and Landslides

Floods, droughts, and landslides are natural disasters that profoundly impact landscapes and communities. Floods occur when water exceeds normal levels, inundating areas,droughts signify prolonged water scarcity, affecting agriculture and ecosystems, and landslides involve the downward movement of rock and soil, posing threats to settlements. These events, driven by various environmental factors, demand comprehensive strategies for mitigation and management.

Watery Onslaught: Understanding and Tackling Floods

• Definition: A flood is a natural disaster, an overflow of water that submerges land which is usually meant to be dry. 
  • While it may occur along river banks, lakes and sea coasts, river flooding is the most common natural disaster of all around the world.
  • Inundation of land and human settlements by the rise of water in the channels and its spill-over presents the condition of flooding. 
• Floods are relatively slow in occurrence and often occur in well-identified regions and within the expected time in a year.

Causes of Floods: Nature Disaster and Human Impact

• Diverse Causes: Floods, as a natural disaster, can result from various factors, including storm surges in coastal regions, prolonged high-intensity rainfall, ice and snowmelt, 
  • Reduced infiltration rates, and the presence of eroded materials in water due to increased soil erosion.
• Amplifying Factors of Floods: Indiscriminate deforestation, unscientific agricultural practices, disturbances along natural disaster drainage channels, and 
  • The colonization of floodplains and riverbeds collectively increase the intensity, magnitude, and gravity of floods.

Flood Hazard Zones

Distributional Pattern of Floods in India: Regional Vulnerabilities

• Rashtriya Barh Ayog:  (National Flood Commission), a natural disaster authority,  identified 40 million hectares of land as flood-prone in India. 
• Most flood-affected states: Assam, West Bengal and Bihar, face the recurring challenge of this natural disaster.
• Vulnerable to Occasional natural disasters: Most of the rivers in the northern states like Punjab and Uttar Pradesh. 
• Sometimes, Tamil Nadu experiences flooding during November-January due to the retreating monsoon, adding to the complex dynamics of this natural disaster. 

Flood Fallout: Agriculture, Infrastructure, and Human Toll

• Agricultural Devastation: Floods destroy valuable crops every year.
• Loss of Infrastructure: It damages physical infrastructure such as roads, rails, bridges and human settlements.
• Human Displacement and Livestock Loss: Millions of people are rendered homeless and are also washed down along with their cattle in the floods. 
• Health Hazards:  It also spreads diseases like cholera, gastro-enteritis, hepatitis and other waterborne diseases.

Positive Consequences of Floods: Fertile Silt and Agricultural Gains  

•  Fertile Silt Deposition: 
  • Every year, floods deposit fertile silt over agricultural fields which is good for the crops. 
  • Majuli (Assam), the largest riverine island in the world, is the best example of good paddy crops after the annual floods in Brahmaputra. 
• However, these benefits are minor compared to the significant losses incurred.

 Flood Mitigation: Strategies for Safer Communities

• Construction of flood protection embankments in flood-prone areas. 
• Construction of dams, afforestation.
• Discouraging major construction activities in the upper reaches of most of the flood-creating rivers.
• Removal of human encroachment from the river channels and depopulating the flood plains. 
  • This is particularly true in western and northern parts of the country which experience flash floods.
• Cyclone centres may provide relief in coastal areas which are hit by a storm surge.