What is the best way to filter your water? Nadir Surani Mulgrave School Floor Location : J 75 P

The topic of my science project is "What is the best way to filter your water?" The reason I chose this topic was because of the high turbid levels in November 2006. The GVRD recommended against drinking tap water and to filter or boil the water so I wanted to research a way to have safe drinking water for future emergencies. Some people did not have power, so they were unable to boil water or get bottled water. Also, B.C. sits on a major earthquake fault line and is warned of a major earthquake. In the event of an emergency like this, we will know how to filter drinking water without power. My hypothesis was that if the water had been filtered correctly, then the best way to get the water clean is to first strain it, second filter it, and finally add a chlorine solution.

I took three samples of boiled, sliced potatoes and used different types of filtered water on the potatoes to see which one gave me the most growth of mold. My filter was made by lining a large funnel with a coffee filter on the bottom, followed by charcoal briquettes on top and glass pebbles. I used a regular kitchen strainer to strain the water. I used my filter that I prepared to filter the water. Three different types of water that I filtered were "the strained water", "the strained and filtered water", and "the strained, filtered and chlorinated water". I added chlorine to the last type of water to further kill the bacteria.

I took pictures of observations on day 3, 5 and day 7 to show the growth of mold on the three specimens. I concluded that the dirtiest water would result in the most growth of mold. My graph of Quantitative Observations showed that the Strained, Filtered and Chlorinated sample was the cleanest and resulted in the least amount of mold growth on the potato. There were a few plateaus noted on days 1 to 2, 3 to 4, and 5 to 6.

In addition, I contacted the GVRD for further information on our drinking water and turbidity levels in November and December. I plotted this on a graph which shows the unusual spike in November.

For household use, I also researched and found further information that I added to my display board titled "How do I purify water in an emergency." The conclusions of this experiment matched my hypothesis that the cleanest water is achieved by firstly straining it, secondly filtering it and finally, adding a chlorine solution.