Potable Water

• What is the main focus of this video lesson?

  Difference between potable and pure water
• Why is drinking water essential for human life?

  It is necessary for hydration and bodily functions
• What defines potable water?

  Water safe for drinking
• What are the acceptable levels of dissolved salts in drinking water?

  They must be sufficiently low
• What types of microbes should drinking water not have?

  High levels of bacteria
• What is the difference between potable water and pure water?

  Potable water contains dissolved substances
• What provides most of the UK's potable water?

  Rainwater
• Where does rainwater collect in the UK?

  In aquifers, lakes, rivers, and reservoirs
• What is the first step in producing potable water from fresh water?

  Use a good source of fresh water
• What is the purpose of filter beds in water treatment?

  To remove leaves and suspended particles
• How is water sterilized in the UK?

  Using chlorine
• What alternatives to chlorine are used for sterilization in some parts of the world?

  Ozone or ultraviolet light
• What is a significant source of fresh water in the UK?

  Rivers
• What is the problem with fresh water in many countries?

  It is scarce and may be too salty
• What is seawater characterized by?

  High levels of dissolved minerals
• What process is used to produce potable water from seawater?

  Desalination
• What is one method of desalination mentioned?

  Distillation
• What is another method of desalination mentioned?

  Reverse osmosis
• What is a common drawback of both distillation and reverse osmosis?

  They require large amounts of energy
• What is the impact of the energy requirement for desalination processes?

  It makes them very expensive
• What are the steps to produce potable water from fresh water?

  1. Use a good source of fresh water
  2. Pass water through filter beds
  3. Sterilize the water to kill microbes
• What are the steps to produce potable water from seawater?

  1. Desalination to reduce dissolved minerals
  2. Methods include:

  • Distillation
  • Reverse osmosis