NYC’s waterways are the cleanest they’ve been in 100 years

New York’s waterways have acquired a bad rap for being dirty, disgusting cesspools. But, really, just how nasty are the city’s waters? According to Melissa Rex, director of education at the River Project, the Hudson River is the cleanest it has been in 100 years and home to a booming ecosystem. “The biodiversity of the Hudson is actually pretty great,” says Rex. “There are more than 250 different fish species and a countless number of invertebrates living in the Hudson River estuary’s ecosystem.”

But the rivers that surround Manhattan still contain trace amounts of chemicals, like polychlorinated biphenyl (PCB), which the River Project and other organizations are working to eliminate through various dredging projects. One of the biggest issues concerns the 20 billion gallons of fecal water that, every year, flows into New York’s rivers due to outdated sewer infrastructure. The so-called combined sewer overflow (CSO) system routes excess sewage into the city’s waterways during rainstorms or rapid snowmelt.

But, overall, the water is becoming a lot less shitty. For instance, improvements are moving in the right direction at one of the city’s most notoriously polluted waterways, the Gowanus Canal. After decades of companies dumping their industrial waste into the 1.8-mile stretch, the channel is lined with 10 feet of toxic sludge. In 2010, the U.S. Environmental Protection Agency designated the area a Superfund site and began to dredge up the gooey grossness (often described as “black mayonnaise”). This spring, the Fourth Street Basin was the first portion of the canal to be declared clean in more than 100 years.

Photograph: Courtesy CC/Flickr/Lukas Schlagenhauf

Perhaps the most inspiring example of this environmental progress comes from the Billion Oyster Project. It’s estimated that, in the 1700s, New York Harbor contained 350 square miles of oyster reefs, accounting for roughly half of the world’s oyster population at that time. While the reefs are now all but absent from NYC’s waters, the initiative hopes to bring back the bivalve to filter the water and increase aquatic plant life.

However, the biggest sign of progress that Rex cites also happens to be one of the—physically, at least—smallest. “We began catching seahorses about 20 years ago, which we never had before,” she says. “They’re a good marker of cleanliness because they’re extremely sensitive to pollution. Since then, we’ve been collecting them in increasing numbers every year.”