How Can Your Faucet Save Water?

Objective

In this experiment you will test several water saving products to measure how much they reduce the flow of water through the faucet.

Introduction

How much water does your family use? Trying to use less water is important because water is a limited resource. Learning about water conservation issues and water saving tips can help you use less water. Many water saving tips focus on your habits and actions, like not letting the water run while you brush your teeth. But there are also many things that can be done to save water that have to do with how a structure is built.

The plumbing fixtures in your house can be water wasters or savers, depending upon the products being used. One simple way to reduce water use in your home is to install low-flow faucets or aerators in your kitchen and bathroom sinks. These products save water by reducing the water flow and adding air to the water stream so that less water comes out of the tap over the time you have it on. These products are usually simple to install and can be bought at the hardware store.

In this experiment you can test several water saving products to see which ones do the best job saving water. You will do this by measuring the flow of water in gallons per minute (GPM).

Terms, Concepts and Questions to Start Background Research

To do this type of experiment you should know what the following terms mean. Have an adult help you search the internet, or take you to your local library to find out more!

water use and conservation
flow rate
gallons per minute (GPM)
low-flow faucet
aerator

Questions

How much water can a low-flow faucet or aerator save?
Which type of product works best?
Can you estimate the potential savings for a home, school, or large office building?

Bibliography

Learn all about water conservation from this website developed by the City of Tampa, Florida. Learn about the issues, become a "Water Ambassador", or read award winning projects. They even offer a special "Drinking Water Award" to the best water conservation project each year! Check it out:
City of Tampa, 2006. "Water Education and Conservation," Tampa, FL. [accessed June 23, 2006] http://www.tampagov.net/dept_Water/conservation_education/
AWWA, 2006. "Water Wiser," Denver, CO: American Water Works Association (AWWA). [accessed June 23, 2006] http://www.awwa.org/waterwiser/
This site has a java applet you can use to make printable, color graphs of your data:
NCES, 2006. "Create a Graph," National Center for Education Statistics (NCES) U.S. Dept. of Education. [accessed March 3, 2006] http://nces.ed.gov/nceskids/createagraph/

Materials and Equipment

several faucet aerator attachments from different manufacturers
kitchen or bathroom sink
large collection bowl (not too big to fit in the sink though!)
a large measuring cup
stopwatch
masking tape
tools (a wrench and pliers)

Experimental Procedure

Shop for low-flow faucet aerators from the hardware store. Choose at least 4 different water saving products.
Read the instructions and have an adult available to help you install the hardware on a kitchen or bathroom faucet.
Install the first faucet product by following the manufacturer's instructions. After installing each aerator you will test it for water use before installing the next product. You should do at least three separate tests for each product and then average your results to get better data.
Test each faucet product after installing it by running water for 10 seconds from the faucet into a collection bowl. To keep the flow of water constant, mark where you turn the faucet with a piece of masking tape so that you turn it to the same place each time. To keep the time constant, set a stop watch to 10 seconds and turn off the water when it beeps.
Pour the water from the collection bowl into a large measuring cup and record the amount of water in a data table:
Product Volume Time Gallons per Minute (GPM)
Ounces Gallons Seconds Minutes
You collected water for 10 seconds, but usually the amount of water flow is given in gallons per minute. So you will need to do some calculations to convert your measurements.
First, convert the volume measurement. Since you measured in ounces, and there are 128 ounces in a gallon, then divide your answer by 128 to get your measurement in gallons.
Now convert the time from seconds to minutes. Since there are 60 seconds in a minute, if you divide your answer by sixty it will be in minutes.
To calculate the rate of flow in gallons per minute (GPM) divide the measurement of volume in gallons by the measurement of time in minutes.
After you have all of the products measured in gallons per minute, make a graph of your data. You can make your graph by hand, or use a site like Create A Graph to make your graph on the computer.
Compare the results using your graph. Which products worked the best?

Variations

Calculate the weekly, monthly, and yearly savings of using a faucet aerator. Ask your parent for a water bill and find out how much they spend on each gallon of water. Then use your results to calculate the potential savings. Do the potential savings fall short of, meet, or exceed the initial cost? How long does it take to recover the initial cost with savings?
Should you shower or take a bath? Try a similar experiment to see if a shower or bath will use more water. You can also find low-flow shower heads to test with a similar experiment. What is the best way to bathe and conserve water?
To flush or not to flush, that is the question! Test these water saving household toilet tips. How much water does your toilet use for each flush? How much water could you save by flushing every other time? Can sinking a brick in your tank help reduce the water used?

Credits

Sara Agee, Ph.D., Science Buddies