SWMM56

Flushing the Toilet Has Never Been Riskier Some of today’s sewers were built before bathrooms as we know them existed. It’s time to upgrade. MARY ANNA EVANS   Sep 17, 2015 Amit Dave / REUTERS Flushing toilets enable most Americans to make their own waste disappear as if by magic, but most would be hard-pressed to answer this simple question: When you flush, where does it go? Septic tank owners, about  20 percent of Americans , are most likely to be able to give an accurate answer, because they’re responsible for the maintenance of their own sewage-disposal systems. A flush from one of their toilets sends wastewater to a tank buried on their property, where the waste products separate into solid and liquid layers and partially decompose. The liquid layer flows out of the tank and into a drainfield that disperses it into the soil, where naturally occurring microbes remove harmful bacteria, viruses, and nutrients . The solid layer stays behind in the form of sludge that must be p...