Solar water disinfection (SODIS) is a water purification method that uses the sun to make biologically contaminated water safe to drink.

What makes clean water harder for communities to access?

  • Pollution and climate change
  • How rural a community is
  • Manufacturing & agricultural contamination
  • Plastic waste
  • Poor handling of human waste
A hand holding a discarded dirty plastic water bottle. In the background is a pile of more plastic water bottles

How to Clean Water using SODIS

  1. Fill a plastic bottle with clear water and close the lid
  2. Shake the water bottle to let air mix in
  3. Place the bottles on a roof or rack depending on the weather
    • Sunny: 6 hours
    • Cloudy 48 hours
  4. The sun has destroyed pathogens and the water is now safe to drink!
SODIS Process. 1. Fill a plastic bottle with clear water and close the lid 2. Shake the water bottle to let air mix in 3. Place the bottles on a roof or rack depending on the weather Sunny: 6 hours Cloudy 48 hours 4. The sun has destroyed pathogens and the water is now safe to drink!

Benefits of SODIS

  • Reduces viruses & bacteria in water
  • Recycles plastic water bottles
  • Water taste is not changed much
  • Simple and accessible treatment method for many people
  • Time saved for women allows them to start their own career

Drawbacks of SODIS

  • Does not remove metals or heavily contaminated water
  • Large supplies of clean bottles needed
  • Worry about chemicals from plastic leaking into the water
  • Limited amount of water can be treated at one time
  • Community beliefs about traditional gender roles

THINK-PAIR-SHARE

Other than SODIS, what other ways do communities make water safe to drink?

Compare and contrast one other water treatment method with what you’ve learned about SODIS so far.