Your Berkey water filter has been shown to effectively purify even untreated water. But unfortunately, your water filter can’t protect you from water contamination if you swim in it.

Water Quality State and county authorities issued 24,091 beach closing and advisory days in 2010 due to pollution, primarily from sewage and animal waste, which could expose swimmers to a host of waterborne illnesses.

Sewage Contamination From Cities and Farms

According to the Natural Resources Defense Council (NRDC), the advocacy organization that calculated the beach-closing statistic, pollution from leaky sewer pipes or overflows during heavy rains are a primary source of human sewage pollution in waterways.

In many urban areas, rain runoff from roofs and roads is directed into the same pipes that carry household sewage to the local water treatment plant. During very heavy storms, the system can be overwhelmed and rainwater and untreated sewage simply overflows into local waterways. In more rural areas, poorly contained animal agriculture operations allow rain to wash waste into waterways.

Surfers and Swimmers Get Sick from Contaminated Beach Water

The latest issue of Surfer magazine reports: “Most official county advisories warn to avoid contact with the water for 72 hours after a heavy rain, a three-day buffer to allow the collective runoff to thin to healthy levels.”

Many surfers don’t wait that long, either because they don’t realize they should or they think they tougher than the bacteria in the water. “Surfers sometimes believe that they are immune to ocean-related illness, because they have been surfing that same spot for years, or that the water quality is not as bad as it is hyped up to be,” explains Paloma Aguirre, spokesperson for the San Diego-based environmental organization WiLDCOAST.

Even Sandcastles Can Harbor Beach Bacteria

According to NRDC, it’s not just surfers who are at risk. Swimmers and other beach-goers, especially pregnant women, children, the elderly and those with a weakened immune system need to heed warnings and stay out of the water when bacteria levels rise. Not only that, minimizing exposure to beach sand after an advisory is issued may be just as important.

“Bacteria concentrate in sand as water rises and recedes with the tides, leaving both the wet sand and the dry sand just beyond it more heavily contaminated than the water. Because of this, it is most important to keep beach sand out of the mouths of toddlers. Keeping your hands out of it or washing them after playing in the sand is also a good idea,” explains the NRDC website.

Pollution Illnesses on The Rise

Pollution at U.S. beaches exposes swimmers to a range of waterborne illnesses and may cause stomach flu, skin rashes, pinkeye, ear, nose and throat problems, dysentery, hepatitis, respiratory ailments, neurological disorders and other serious health problems.

It is hard to determine the number of gastroenteritis cases or other diseases caused by swimming in polluted water. There is no national reporting system in the United States to help epidemiologists track national trends, but the Centers for Disease Control estimate that illness from contaminated beach water is on the rise. One study conducted by the agency concluded that 10 percent of Great Lakes beachgoers get sick after swimming.

Fixing Sewers and Protecting the Public from Pollution

RDC and other public health advocates are calling for a variety of reforms that include increased funding for sewer treatment plant upgrades and sewage system repair. The public could also be better protected by improving water quality testing speed, accuracy, and public notification systems.