Water is everywhere. Nearly three-fourths of the earth’s surface is covered by water. However, less than one percent of that water is drinkable. With such a small percentage available for consumption, water quality is very important. All plants, animals, and humans depend on water to live. Humans can live weeks without food, but can only survive a few days without water. We can get our water from a variety of sources. If you live in the middle of the city, you drink city water. If you live out in the country, your water probably comes from a well. Some people even buy purified bottled water. No matter where you get your water, it is essential for human life. But do you really know what is in your drinking water?
Here in the city of Dublin, Georgia, our water comes from the Oconee River. It goes through a plant where they put fluoride in it and send it to our homes. The people who have wells get their water differently. When it rains, the water seeps into the ground and fills an aquifer. The water is then pulled up by a pump into the well. You may think that bottled water is better, but it is really just city water. All these kinds of water have one thing in common–bacteria. Bacteria are tiny, living microscopic creatures. They breed in large groups called colonies. Because there is more air in freshwater, bacteria thrive in it more than salt water. Bacteria may originate from decaying plants, sewage, and animal scat. Bacteria in water have no color, smell, or taste. Consuming water that contains bacteria beyond the acceptable levels may cause a person to develop a fever, diarrhea, abdominal cramps and even hepatitis. The only way to find out if your water has bacteria in it is to test it.
Most cities test their water each year and publish results of their findings. These reports not only show the amount of bacteria in the water supply, they also indicates the amount of bacteria that is allowable. Bottled water is tested periodically by the bottler to monitor its bacteria levels. Those who rely on a well for their drinking water are responsible for testing their own water.
An experiment you can do with water and microbiology is water quality testing. You can take water from different sources and study each one to determine how much, if any, bacteria are initially present. Additionally, you can test the same water over time to determine if the bacteria are multiplying. These results may prove interesting or shocking, depending on the results. You could also use various water treatment chemicals to determine their effectiveness on treating bacteria filled water.
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