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Conservation House
Fast Facts
     What is H2O?
     Be a Scientist
     Clean Water
     Leak Seeker
     Water in Food
     Salt vs. Fresh Water


Clean the Water
Water in lakes, rivers and swamps often contains impurities that make it look and smell bad. The water also may contain bacteria and other organisms that can cause disease. How can we get this water clean enough to drink?


Water Treatment Interactive

See how water is pulled from Lake Mead and treated at the water treatment facilities.

treatment plants clean water using some
or all of the following processes:
  1. Aeration
  2. Chlorination
  3. Ozonation
  4. Filtration
  5. Disinfection with ultra violet light

It's your turn to clean dirty water. Follow the experiment below.

You will need:
  • A homemade filter (sock, cotton, paper towels, coffee filter, sponge, sand)
  • Cooking oil
  • Clean water
  • 2 empty plastic bottles - (1-liter soda bottles are okay but one bottle should be clear) 
  • Dirt & grass
  • Dish soap
Begin the experiment:
  1. Fill one of your bottles half-way with water from the faucet.
  2. Put cooking oil, dish soap and some dirt and grass into the bottle of water.
  3. Shake the bottle to mix the dirt around.
  4. Take the unused bottle and cut it in half. Rest the top half in the bottom half (see diagram below).
  5. Grab your filter and stuff it in the "neck" of the bottle you just cut.
  6. Pour the dirty water from the first bottle through the filter on the second bottle.
  7. Does the water poured through the filter look cleaner? It's not clean enough to drink, so don't try it!
Making discoveries:
  1. Compare the water you filtered to the dirty water. How are they different?
  2. Can you get dirty water cleaner? How?
  3. How hard is it to clean dirty water?
  4. Share what you learned with your friends and family.