Rivers, Floods and Management. Case study 1 - Asia

HideShow resource information
View mindmap
  • South Asia, 2007.
    • When?
      • Usually late summer
        • Particularly bad in July and August 2007.
    • Where?
      • South Asia floods most years.
        • Bangladesh
        • India
    • Why?
      • Monsoon climate
        • 80% of rain falls in just four months.
        • Came suddenly after a very dry, early summer.
      • South Asia is low-lying land.
        • Bangladesh
          • Relief
            • 90% of land is less than 10 meters above sea level.
      • Himalayas
        • Melting snow and ice
          • Later summer
          • Increases the Brahmaputra rivers discharge
      • Physical Factors
        • Heavy rainfall
          • a record of 169.5mm in 24 hours on 22nd of July.
          • 900mm total rainfall in July.
        • Monsoon climate
          • 80% of rain falls in just four months.
          • Came suddenly after a very dry, early summer.
        • Saturated soil
          • Long duration of heavy rainfall.
            • Heavy rainfall
              • a record of 169.5mm in 24 hours on 22nd of July.
              • 900mm total rainfall in July.
            • Increases surface runoff
              • Increases river discharge.
      • Human Activities
        • Deforestation
          • Nepal
            • Himalayas.
          • Less rain was intercepted
            • Increasing river discharge
        • Growth of urban areas
          • Due to migration
          • Impermeable land
            • Increases surface runoff
              • Increasing river discharge
        • Collapse of old earth dams
          • In Madhya  Pradesh,  India.
          • Led to rapid release of high volumes of water
            • Causes further flooding
    • Social impacts
      • Over 2000 deaths
        • Reluctancy to evacuate
          • Leaving live stock and crops
        • Children drowned as they couldn't swim
        • Poor transport links
          • Slow evacuation
      • Water-borne diseases.
        • sewage mixed with wells.
          • Reduced amount of clean drinking water
            • Over 100,000 people caught diseases.
              • Dysentery
              • Diarrhoea
      • 25 million made homeless
        • 112,000 houses destroyed in India.
          • Mud bricks became saturated by rainfall/floodwater
      • Education
        • 4000 schools were affected
        • 44 schools totally destroyed
    • Economic impacts
      • cost of flood
        • $1 billion USD
        • Factories closed around Dhaka
      • Widespread loss of livestock
        • Cattle
        • Sheep
        • Lamb
      • 550,000 hectares of land destroyed
        • Land couldn't be used to plant rice crops at rice crop peak time
      • 10000km of road destroyed.
        • Accessibility
      • Debt increased
        • Individually (farmers etc...)
        • Nationally (government)
    • Environmental impacts
      • Deposition of fertile silt on the flood plains
      • Water pollution
        • Rivers polluted
        • Sewage contamination
          • Rivers polluted

Comments

mattbrennan

can't read it

Similar Geography resources:

See all Geography resources »See all Case studies resources »