WR Partnership Monitors
E. coli in the Watershed
By Sandy Vondrasek Cooch

Want to know the levels of E. coli bacteria in local streams and rivers before going in for a swim? The White River Partnership’s weekly monitoring reports are available to the public.

"Because the White River watershed is a popular destination for swimming, paddling, fishing, and tubing," said the Partnership’s executive director, Mary Russ, "we have been keeping a close eye on E. coli levels in an effort to understand and combat potential sources of pathogens.

"And because of its close relationship to public health, we make the E. coli results available to the public each Thursday, via email, mail and our website," she said. "If you would like to receive the weekly results directly, please email us at matt@whiteriver
partnership.org or call 767-4600."

Interest in swimming hole waters heightened late last month, after two young central Vermont girls contracted E. coli infections that progressed into a very serious and rare complication that attacks kidneys and red blood cells. The two girls, one of them from Randolph, remained hospitalized in Boston hospitals this week.

E. coli bacteria live in the intestines of all warm-blooded animals. There are hundreds of strains of E. coli, and only some pose a health hazard to humans. There are also many ways to contract an E. coli infection—including from undercooked meat, contaminated fresh foods such as lettuce, unpasteurized drinks, via person-to-person contact, and from swimming in contaminated water.

Girls Infected

Preliminary testing indicates that the two girls who fell ill in June were infected by different strains of the O157:H7 strain of the E. coli bacterium, according to the state epidemiologist. The source of either of the girls’ infections has not been determined, but the fact that the strains are different makes it likely they picked up the infection from different sources, state officials indicated.

One of the girls, from Barre Town, contracted her infection a few days after swimming in the North Branch of the Winooski River in Montpelier, but it is not clear that river bacteria were source of her infection.

This week, Mary Russ explained that E. coli colonies in open waters show that fecal material from somewhere—leaking septic systems, waterfowl, livestock, wild animals, or pets—is entering the water. When E. coli are detected in waters, "there is a potential for the water to contain pathogens that could make people sick," she explained.

For the past six years, 22 dedicated volunteers have kept tabs on 26 sites throughout the White River watershed, measuring water temperature, clarity, and electrical conductivity (a measure of dissolved salts), and also collecting water samples that are tested for E. coli at the WRP’s Rochester office, Russ said.

Numbers of E. coli colonies reliably peak after heavy rains, which can send polluted run-off into local waters. Bacteria numbers typically subside back to "base numbers" within 24 hours, Russ indicated.

Standards Exceeded

For example, E. coli counts for the Third Branch in Randolph, at 125 and 148 (colonies per 100 millileters of water) for the first two Wednesdays in June, soared to 755 on June 20, one day after a heavy rain.

According to Russ, since WRP began monitoring in 2001, almost half of the sites routinely have had E. coli counts over the state’s accepted safe swimming standard of 77 organisms per 100 ml of water.

However, because Vermont’s standard is the strictest in the nation, the WRP also uses the Environmental Protection Agency’s national standard of 235 organisms per 100 ml sample. Only one monitoring site on the Middle Branch regularly exceeded this federal standard in 2006, using counts averaged over the course of the summer.

That is an improvement over prior years, she said, when multiple sites had averages over the federal standard.

Russ said that Central Vermonters "are lucky to have waters that are fishable and swimmable a majority of the time."

However, it’s important to use discretion, she indicated: "As a middle-aged, healthy adult, I would think twice about entering the water if it exceeded (the federal standard) all the time. If I had kids, I might hesitate to put them in the river after a rain storm."

Russ said that the Partnership is investigating ways to do more public education, possibly to include posting counts and information at popular swimming and fishing sites.

The White River Partnership is a community-based non-profit organization committed to bringing together people and local communities to improve the long-term health of the White River and its watershed. For more information about the WRP and it water-quality monitoring program, visit www.whiteriverpartnership.org or call 767-4600.

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