Sustainable development and water

• Finite resources will run out
• Renewable resources do not run out and can be replenished
• Potable water is safe for humans to drink
• Potable water is not pure and contains impurities
• Distillation process


  • Heat sea water until it boils
  • Salt remains in liquid
  • Steam produced is pure water
• Distillation is unsustainable and requires large amounts of energy
• Reverse osmosis process

  • Water put under high pressure
  • Pushed through semi-permeable membrane
  • Salt is trapped leaving pure water
• Reverse osmosis is expensive and unsustainable
• The Haber process enables humans to produce fertilisers that allows for intensive farming
• Waste water treatment processes

  • Screening + grit removal for large particles
  • Sedimentation removes small particles
  • Anaerobic treatment removes sludge
  • Aerobic bacteria kills harmful bacteria
• How can you obtain potable water?

  1. Filtration
  2. Desalination (Distillation and Reverse Osmosis)