Public Health Alerts

Weekend swimming: Don't drink the water

By Candace Page
Free Press Staff Writer

June 30, 2006
Wayne Gross offers two theories about rain and pollution at swimming beaches around Vermont this holiday weekend. Take your pick.

Theory 1: Heavy rain washes animal feces from the land into the water. Result: A potentially unsafe level of illness-causing bacteria could occur along some shores.

Theory 2: After the incessant rains of May and June, the land around Lake Champlain already has been scrubbed clean and the likelihood of contamination has dropped.

Gross, Burlington's director of parks and recreation, leans toward Theory 2.

"Historically, the worst problems come with a big rain after a long dry spell. With all the rain we've had, I doubt that there will be a problem. There's been a continual cleansing of the watershed," he said.

Across Vermont, communities including Burlington, Colchester, Shelburne and Williston have begun weekly or twice weekly bacteria testing. The Vermont state park system takes weekly samples at 32 swimming areas on 17 bodies of water.

The good news: Beach water quality problems are increasingly rare, thanks to sewer system improvements, and generally do not last long when they occur.

The bad news: Water testing isn't very helpful to swimmers if the contamination is from a transient source -- storm-carried runoff, for example -- because by the time the test results are posted, the problem is most likely over.

So what's a swimmer to do?

Neil Boyden, public works director in Williston and the man in charge of testing at the public beach on Lake Iroquois, has a practical suggestion.

"Don't swallow the water," he said this week. "It's only a problem if you ingest the water -- and it's never a good idea to ingest lake water."

Cautious with children

Tests at Burlington beaches on June 23 found levels of the illness-causing bacteria E. coli above the state standard at the south end of North Beach and the north end of Leddy Beach. Other spots along those beaches and at Oakledge Park cove showed much lower levels. The beaches were to be retested Thursday and the results posted on the Parks and Recreation Web site today.

E. coli are bacteria found in the feces of warm-blooded animals, including humans, and are an indicator that the water could make people sick if they swallow it.

Vermont's safe swimming standard is no more than 77 E. coli colonies per 100 milliliters of water, which is about a third of a 12-ounce soda can. When tests exceed that level, "no swimming" signs go up until daily tests show the bacteria have dropped to safe levels.

High levels were found June 20 in the Huntington River, site of popular swimming holes. Bacteria levels were above the state swimming standard at all 17 sites in Huntington and Richmond. From Huntington Gorge downstream to the Winooski River, readings ranged from 193 to 411 colonies per 100 milliliters.

Aaron Worthley, who leads the volunteer testing program in Huntington, pointed out that Vermont's swimming standard is the most stringent in the country -- well below the U.S. Environmental Protection Agency standard of 235.

Worthley said the advice he gives swimmers, based on guidance from environmental regulators, "is to use the EPA's 235 as a safe cut-off, but in that range between 77 and 235 be careful not to swallow the water and be cautious about young children." No swimming at Blanchard

One spot that won't be open for swimming this weekend is Blanchard Beach in Burlington's South End, although water quality there has improved dramatically.

The beach lies near the mouth of Englesby Brook, a rivulet that carries city stormwater and has been a source of continuous contamination. A year ago, then-Mayor Peter Clavelle inaugurated another in a series of stormwater control and cleanup projects along the brook.

"Next year at this time, we'll be swimming there," Clavelle said then.

Clavelle was both right and wrong. Weekly water tests at Blanchard Beach last summer found only one bacteria reading that would have justified closing the beach, if it had been open.

Nevertheless, the beach remains closed. Stormwater improvements were not completed until late fall. City officials want to see another summer's worth of results before they reopen the beach.

"I think the mayor was being a little optimistic," Gross said. Contact Candace Page at 660-1865 or cpage@bfp.burlingtonfreepress.com