Science Fair Project on Testing Drinking Water

You are intelligent enough to know that the purpose of most science fair projects is to teach students how to use scientific methods to solve problems on their own. A science fair project can allow students, parents, and teachers to make new discoveries together. One of those discoveries might be how clean your drinking water is.

Students may expect faucet water to be clean, but is it? A science fair project on testing drinking water can help them learn what is in the water they use. This outline will help them and you conduct a drinking water test.

State Your Hypothesis

A good example might be, “If I test drinking water from different sources, which will I find to be the best for my health?” A poor example would be, “If I drink tap water, what happens?”

Background Research

Learn all that you can about what water may contain. Research the effects of various contaminants, minerals, etc.

Develop a Drinking Water Test

What kind of drinking water test will you use? What kinds of drinking water will you test? Will you buy a kit, or simply order appropriate test materials? How will you collect the water to be sure you do not change its content?

What You Need for Drinking Water Tests

Students will need Colorimetric test strips for many drinking water tests. Kits are available from science fair websites. Water Safe Drinking Water Test is an EPA standardized, laboratory certified simple kit that identifies harmful levels of 8 different common contaminants in water: bacteria, chlorine, lead, nitrates, nitrites, pesticides, pH, and water hardness.

Predict Results

Write out a prediction of what you expect. Will your city tap water be the best water for your health? Should your family pay money to drink only bottled water? What do you predict your drinking water test will reveal?

Conduct Your Drinking Water Test

Students may choose from many drinking water tests. Here are a few possible tests. Younger students may want to use only one. Older students may combine a series of drinking water tests.

1. Basic: A basic drinking water test might allow students to test water for alkalinity, chlorine (both free and total), nitrate and nitrite, pH, and water hardness. What is the basic make-up of your water?

2. Bacteria: Along with a basic drinking water test, you might test for bacteria in the water. Water from a drinking fountain may show bacteria that collect on the bubbler and wash into the water.

3. City Water: What is in municipal drinking water? You can use the basic drinking water tests above, but check, too, for metals and sediment. Are corroding pipes contaminating the water?

4. Well Water: Since the government does not test private wells, there may be contaminants in the water taken from them. What might you find? Would you expect more sediment or less? Would your drinking water test be likely to find pesticides if the well is near a farm or garden where they are used?

5. Bottled Water: Is bottled water really pure? Is it better than tap water or worse? Run a drinking water test on it and see what you find.

6. Water Cooler: If your water cooler is typical, a large five-gallon bottle is turned upside down into the drinking water crock. Might there be germs on the bottle top? Will a drinking water test show up these germs?

7. Pet Water Bowl: Pet drinking water tests will show you what your pet’s water contains. The pet bowl should not be cleaned right before the test. Allowing your pet to drink from it will show whether or not the water is still pure enough for humans.

Repeat Your Drinking Water Test

A good scientist repeats tests to be sure the results are the same. You will not have accurate results if you run your drinking water test only once.


Analyze the results of your tests. Which water is purer? Which one tastes better, looks better, and smells better? From your analysis, do you think your prediction will hold up?

Arrive at Conclusions

Draw conclusions from your drinking water test. Look at all the evidence and decide what it means in regard to healthy drinking water.

1. Which water contains the fewest contaminants?

2. Which water contains the fewest bacteria?

3. Which water is best for your health?

Prepare Your Display

Decide early how the display will look and leave plenty of time to complete it. Will you have photographs? Will you have clear glasses containing water samples? How will you display used test strips?

Most science fair projects require a display board to communicate your work to others. A three-panel display board that is 36″ tall by 48″ wide when unfolded is standard. On your board, include these elements.

1. Title: Make it catchy – and big enough to read from across a room.

2. Hypothesis and research: Organize your information from top to bottom, left to right, as though you were planning a newspaper page. Put Hypothesis and research information on the left side of your board.

3. Materials and procedures: Place this information just under your title in the middle of the board.

4. Data / Charts / Photos: These go at the bottom of the center part of your board.

5. Results and conclusions: The right side of your board holds the final information about your drinking water test.

A science fair project on testing drinking water can be interesting and exciting, appropriate for any age student. The results may surprise everyone.