"In 2010, a tornado hit Brooklyn, sending rain barreling down for several hours. Someone in Gowanus began recording video of a tide of brown water creeping up the Gowanus Canal. The greenish hue of the pre-storm water is overcome, bit by bit, by the dark, ruddy wave. The videographer gets closer, and someone gags loudly in the background. The water stinks.
“Oh, this is bad. Look at that, a used condom.” The gagging person dry-heaves twice.
When it rains in New York City, raw sewage bypasses treatment plants and flows directly into city waterways. Even a relatively small amount of storm water—one-twentieth of an inch of rainfall—can overwhelm New York’s aging sewer system and trigger the Combined Sewer Overflow (CSO) system, which discharges the rainwater and raw sewage into the many CSO outfalls dotting the edges of the city. CSOs, due to their contribution of fecal coliform, are the single largest source of pathogens to the New York Harbor system, according to the New York Department of Environmental Protection."