On the Potomac, Swimming in Risk
Saturday, July 14, 2007
Is it safe to swim in the Potomac River? No. Yes. Probably. Usually. Never.
This simplest of summer questions turns out to have a wide variety of answers, depending on who in the Washington area is answering. The District bans swimming. Prince George's County advises against it. But just upstream, Montgomery County says the river is generally safe.
Meanwhile, kayakers, sailors and others spend summer weekends on -- and in -- a river with levels of fecal bacteria that frequently exceed federal standards. Many of them say they've seen few official warnings about the danger.
This week, a proposal to hold a triathlon along the river provided a case study in the murky status of the Potomac's health. District officials approved the plan, but said they might cancel the swim course in the unlikely event that . . . it rains.
"It might not be safe to swim in every day, but it could be safe to swim in any day," said Charles Brodsky, organizer of the Nation's Triathlon, whose competitors will swim 1.5 kilometers -- about nine-tenths of a mile -- in the river Sept. 29.
The Potomac, placid as it looks from downtown Washington, poses a number of threats to swimmers. In some sections, rapids and strong currents can pull them under. The bottom is studded with broken glass, shopping carts and other debris. Less ominous, but sometimes harder to detect, is the threat posed by disease-causing bacteria in the water.
The Potomac is usually thought of as a place where pollution problems were beaten: For decades, it was used as a sink for raw sewage and toxic chemicals, until in 1965, when President Lyndon B. Johnson called the river "a national disgrace." Since then, thanks in part to cleanups at sewage plants, the Potomac's water has become clearer, and wildlife such as largemouth bass and bald eagles are thriving.
But, despite this comeback, the river still has a stubborn problem with fecal bacteria. These microbes are found in both human and animal waste, and they can indicate the presence of pathogens that can cause infections, intestinal distress and other symptoms.
"If you had just flushed your toilet and all of a sudden became 6 inches tall, would you want to swim in . . . that water?" asked Ed Merrifield, an environmental activist whose title is Potomac Riverkeeper.
Some of these bacteria are from livestock farms in the Potomac's rural headwaters. Others come from the suburbs, where droppings from geese and household pets wash down with rainwater. In the District, an outmoded wastewater system -- now at the beginning of a 20-year cleanup plan -- still dumps raw sewage into Potomac tributaries during storms.
This pollution gets worse after a rain and better during dry periods. But in all, last year, 32.5 percent of the tests on a section of the Potomac in Washington found bacteria levels higher than the federal government deems safe for swimming.
To some environmental groups, this evidence closes the case: The Potomac is not a good place to submerge one's body.