Water Filter Project

Through the natural water cycle, the earth has recycled and reused water for millions of years. Water recycling, generally refers to projects that use technology to speed up these natural processes.

There are a lot of benefits to recycling water. One benefit is that clean fresh water is hard to come by. Recycling affords many more people clean water. Singapore uses a lot of recycled water. Another benefit is that when you recycle water it decreases the pollution that would be poured into the sea. Dirty water if not recycled would simply be put in the sea causing serious damage to the ecology of the region.

This project will show you how different materials filter different things out of the water. You will not be cleaning the water on a microbiotic level so you may want to hold off on using this as a method to clean your drinking water.

What you need:

• 2-liter soda bottle cut in half (by an adult)
• gravel, sand, wood charcoal and cotton balls for your filter
• dirty water – you can make it by adding cooking oil, coffee grounds, tea leaves pieces of paper, and tiny pieces of styrofoam to water

What to do:

1. Put the top half of the soda bottle upside-down (like a funnel) inside the bottom half. The top half will be where you build your filter; the bottom half will hold the filtered water.
2. Put the material for the filter into the top half of the bottle, one layer at a time. Think about what each material might remove from the dirty water and in what order you should layer the materials.
3. Pour the dirty water through the filter.
4. Watch as the dirty water runs through the materials. Can you see what is happening?
5. Take the filter apart and look at the different materials. Is it easy to see what each layer filters? Are they different materials?
6. Clean the bottle and do the experiment again or have several bottles ready so that you can see if the order of the filter material makes a difference.
7. What other materials do you think would work for filtering water?

Something to think about is the economy of the filter. Is it expensive or inexpensive to make. Can people who have very little money afford to buy this filter so that they can have clean water? Are there more affordable materials that could be used?

Interesting facts about WATER:

• Water moves around the earth in a water cycle. The water cycle has five parts: evaporation, condensation, precipitation, infiltration and surface run-off.

• There is the same amount of water on earth as there was when the earth was formed. This means that the overall amount of water on our planet has remained the same for two billion years.

• The water that came from your faucet could contain molecules that Neanderthals drank.

• There are two kinds of water – salt water and freshwater. Salt water contains great amounts of salt, whereas freshwater has a dissolved salt concentration of less than 1%. Only freshwater can be applied as drinking water.

• If all the world’s water were fit into a gallon jug, the fresh water available for us to use would equal only about one tablespoon.

• Over 90% of the world’s supply of fresh water is located in Antarctica.