How to Test Water for Bacteria

Public water systems are required by the Environmental Protection Agency (EPA) to monitor and test public drinking water and to provide their customers with an annual report, called the Consumer Confidence Report. However, if your drinking water comes from a dug private well, an older water system, or a spring-fed or cistern-type system, then they are very vulnerable to bacterial contamination, especially if they are not sealed properly. If your drinking water comes from a source other than a public system, then you alone are responsible for testing your water regularly for pathogenic bacteria.

Things You'll Need

• Confidential drinking water bacterial purity test kit from a state certified water testing laboratory

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Instructions

Testing Your Water Supply

• 1

  Contact your city, county or state department of health and human services for a list of approved, state-certified water testing laboratories. You can also call the Safe Drinking Water hotline at [phone] to find the one closest to you, or online at epa.gov/safewater/labs.

• 2

  Pick up a confidential drinking water bacterial purity test kit from the lab of your choice, or have them mail one to you.

• 3

  Follow the test kit's detailed instructions exactly on how to properly collect the water sample and avoid cross contamination.

• 4

  Fill out the information form accurately and completely with the date and time of collection and your return address. The lab must receive your sample within 30 hours (or however long the lab determines) after it's collected. If there is no time and date listed, the lab will assume it's more than 30 hours old, and will not test it. For this reason, it's best to hand-carry your sample immediately to the lab instead of mailing it. If you don't list your return address, the results won't be mailed to you. Make sure your return address is listed and is accurate.

• 5

  Buy bottled water or boil your water vigorously for one minute before drinking it or cooking with it if the lab test confirms the presence of significant amounts of bacteria or other contaminants. Boil it vigorously for three minutes if you live in an altitude more than 6,562 feet above sea level.

• 6

  Follow the site or situation-specific instructions and recommendations of your local public health department officials on what to do to eliminate the source of your water's contamination and how to disinfect your water supply.