Colombo Floods, Sri Lanka 2016 (Case Study)

• Causes

  Seven regions of the South Asian island nation, including the capital Colombo, experienced torrential rainfall of over 400mm over the weekend, twice the amount of rain that falls in a month.
• Social impacts

  Short term

  • 73 people died
  • Hundreds of thousands forced to evacuate
  • 243,000 in temporary shelters
  • Cyclone Roanu killed 6 and forced the evacuation of 500,000

  Long term

  • Huge landslides buried victims in 15m of mud
  • Swallowed 3 villages
  • 21 confirmed dead
  • 123 missing
  • Rural-urban migration
• Economic impacts

  Short term

  • Over 200,000 homes were damaged or destroyed, with immediate repair and rebuilding costs estimated at around $1 billion.
  • Thousands of businesses were affected, leading to an estimated loss of approximately $200 million in income and productivity.

  Long term

  • Damage to roads, bridges, and public buildings was substantial, with repair costs estimated at around $500 million.
  • GDP growth reduction of around 0.5% for the year, translating to a potential loss of about $750 million in economic output.
• Environmental impacts

  Short term

  • 2,343 square kilometres underwater
  • Habitats degraded for cherry barb fish
  • Soil and river bank erosion
  • More landslides due to saturated land

  Long term

  • Fish used flood for breeding
  • Increased abandoned land
  • Poisonous contaminants from dying plants