Swim Water Testing

Do you know the quality of the water at your favorite swimming place?

Rivers, ponds, lakes, and streams may contain disease-causing microorganisms. Swimming in these waters may result in health effects such as minor skin rashes, sore throats, diarrhea, or more serious problems .

Children tend to spend more time in the water than adults. They are also more likely to swallow water when swimming and for this reason, they are more likely than adults to get sick. However, infants, the elderly, and people with weakened immune systems have the greatest chance of becoming seriously ill.

How often should swimming water be tested?

The Health Department recommends that swimming water at town beaches and other publicly used recreational areas be tested at least once a week from Memorial Day to Labor Day. Additional testing may be warranted after periods of heavy rain when swimming areas are more likely to be flooded by runoff.

People who have a pond or private swimming area on their property should test for water quality periodically throughout the summer months.

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What is swimming water tested for?

Water in ponds, lakes and rivers is tested for Escherichia coli, commonly known as E. coli., to determine whether it is suitable for swimming. E. coli is a bacterium that is almost always associated with human or animal feces. Its presence in water means that other disease-causing microorganisms may be present as well.
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When should water samples be taken?

Water samples should be taken at times and locations of greatest swimmer use. Once the sample is taken, deliver or mail it to the laboratory as soon as possible. If you mail the sample, it should be sent either first class or overnight delivery because testing is recommended within 6-24 hours of sample collection.

Testing early in the week leaves time to take follow-up samples in the same week if initial results fail (swim water unsuitable). Normally, at the Vermont Department of Health Laboratory, the results of samples submitted on a Friday will not be available until the following Monday unless special arrangements are made. (Details on test kits, prices, lab schedules)

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Where should water samples be taken?

Water samples should be taken in an area where the water is at least 2 feet deep. Tthe person taking the samples must wade out to a point where the water is between knee and waist deep, and then dip the sampling container into the water. Follow the instructions that are included with the test kit.

What does the E. coli test result mean?

E. coli in water is measured as the number of bacteria found in 100 milliliters (mls) of water. In Vermont, when the test result at a public swimming area is 77 E. coli /100 mls or less, it means that the water is considered suitable for swimming. A result greater than 77 E.coli /100 mls means that the water is not suitable for swimming.
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When should the swimming area be closed?

If the test result is greater than 77 E.coli /100 mls (unsuitable) , the Health Department recommends that the swimming area be closed and posted immediately. The beach area should remain closed, and not re-open, until a follow-up test result confirms that the E. coli level has decreased to 77 E.coli/100 mls or below (suitable).

Follow-up samples should be taken at the same location as the original sample.

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How can I order test kits or get additional information?

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