"With their quaint barrel-like contours and weathered cedar-plank sides, rooftop water towers are a constant on the New York City skyline. And though they may look like relics of a past age, millions of residents get their drinking water from the tanks every day."
"But inside these rustic-looking vessels, there are often thick layers of muddy sediment. Many have not been cleaned or inspected in years. And regulations governing water tanks are rarely enforced, an examination by The New York Times shows.
Even some that are routinely maintained contain E. coli, a bacterium that is used by public health officials to predict the presence of viruses, bacteria and parasites that can cause disease."