How to Test for Fecal Matter in Water

You expect clean, potable water free of contaminants and pollutants. Therefore, it is important to make sure your water supply is free of fecal matter. Fecal matter contains fecal coliform bacteria, organisms that indicate the possible presence of pathogens such as Escherichia coli that can cause illness and disease. Water tests are used to determine if your water is contaminated with coliform bacteria. You can test and make sure your drinking water is safe by collecting a water sample from your house and having it analyzed.

Things You'll Need

• Anti-bacterial soap
• Water test kit
• Clear tape
• Envelope
• Box

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Instructions

• 1

  Contact your city or state health department for a water-testing kit from its laboratories or for a list of approved, state-certified water-testing laboratories. Most labs will mail you a testing kit if you choose its services.

• 2

  Wash your hands thoroughly with anti-bacterial soap and water to prevent cross contamination. Place the petri dish provided in the test kit on a level surface with the lid side up. Make sure you do not touch the inside of the petri dish or open it until you are ready to perform the test.

• 3

  Turn on the water from your chosen sampling location and collect a sample with the pipette provided in the kit. Place the sample into the petri dish and place the bacteria medium into the dish bottom. Quickly replace the lid and swirl the dish until the bottom is covered with the sample and medium. Set for 1 hour to harden.

• 4

  Incubate the dish at room temperature for 48 hours. Count the colonies of bacteria that form on the petri dish. Refer to the chart provided with the test kit to determine your sampling results. Check the dish again after 72 hours to view any slow-growing bacteria that was possibly overlooked.

• 5

  Seal the edges of the petri dish with clear tape. Fill out the information form provided with the test kit. Place the water sample and the completed information form in a padded envelope or box and send it back to the professional laboratory for analysis.