1 in 10 U.S. Beaches Fails Bacteria Test: Survey
Storm-water runoff, including sewage, continues to threaten swimmers' health
"Children are also more likely to dunk their heads under the water or swallow water when swimming, both of which increase risk," he added.
Under the federal Beaches Environmental Assessment and Coastal Health (BEACH) Act, states must test beach water for bacteria. When bacteria levels are too high -- such as after a heavy rain -- beaches may be closed or people might be advised not to swim.
More than 10 trillion gallons of untreated storm water, including billions of gallons of untreated sewage, find their way into America's waterways each year, the EPA said. Historically, this is the largest known source of beach water pollution.
The best way to prevent beach water pollution, said the defense council, is to invest in "smarter, greener infrastructure on land, like porous pavement, green roofs, parks, roadside plantings and rain barrels."
Such improvements enable rain to evaporate or filter into the ground instead of being carried from dirty streets to beaches.