Growing oyster population shows a promising future for the polluted Hudson River

The solution to New York City's heavily contaminated waters may already be located beneath the water's surface: oysters.

According to the New York Public Library, the Hudson River had a flourishing oyster population more than 100 years ago, but over farming and pollution from the city nearly wiped it out. Now, with the help of organizations across New York City, the oyster population is beginning to make a comeback, which could have a positive impact on the waters.

"The great thing about oysters is that they are filter feeders. As they grow they naturally cleanse," said Owen Foote, the treasurer of the Gowanus Dredgers. Along with The River Project, the Gowanus Dredgers are working toward the restoration of these oyster reefs to ensure that New York can have clean water for years to come.

One adult oyster can clean up to 50 gallons of water each day, according to the Chesapeake Bay Foundation. Leaders of the organizations hope that by bringing back the oyster population, they'll also bring back the clean waters of a pre-industrial era.

"We found the biggest oyster that's been seen in the New York Harbor in 100 years," said Cathy Drew, the executive director of The River Project. On average, a single oyster is around three inches long. The oyster found in the Hudson River was eight inches long.

"That's a sign to us that the old remnant population of wild oysters is, to some extent, making a comeback," Drew said.

But the Hudson River still faces major challenges with unclean water. According to a 2018 report released by the New York State Department of Environmental Conservation, 6.25 billion gallons of sewage entered waterways in New York between 2017 and 2018. "The Hudson River received the highest reported overflow volume at over 2 billion gallons," the report said.

The primary cause of sewage pollution, the report found, is the runoff caused by rain and snow that bypasses the preventative measures in treatment plants and manholes.

Despite this, in the past two decades oysters have begun to reappear due to actions being taken by organizations like The River Project and with the help from the community.

On Brooklyn's troubled Gowanus Canal, the oyster restoration project has found less success.

The Gowanus Canal is contaminated with sewage, heavy metals, and pesticides, along with many other pollutants. It is also a Superfund site, which qualifies it for a government-funded cleanup of pollutants and hazardous waste.

But keeping up with the pollution is difficult. Each time it rains, contaminants that flow into the canal would be more than the oysters could keep up with and filter.

To help educate the public, the Gowanus Dredgers are hosting canoe trips and inviting people in the community to come and see the oysters living in the canal. The more the city sees people using the canal, the more likely it may be to fund the oyster program, Foote said.

For the Gowanus, bringing back the oysters restores the hope that other species would thrive there too.

"The true beauty of the oyster is that it's the base habitat for a lot of other aquatic life," Foote said. Trout, herring, and bass could flourish once the oyster population is restored.

Diversity within an ecosystem makes it more sustainable, with each species playing a role that other species depend on for survival. Each species in an ecosystem has a role to carry out, which makes other organisms dependent on the roles that these species achieve.

"It's not too late to reverse (the harm) and bring the old population of oysters back," Drew said.

This article was produced in collaboration with the two-week Institute for Environmental Journalism Summer program, through which high school students explore the nation's most pressing environmental concerns in NYC's urban neighborhoods or Maine's rugged outdoors.

Ruby Germack, 15, is an iGeneration Youth reporter living in Brooklyn, N.Y. See more stories at