Eat Oysters in New York City to Help Clean Up the City’s Waterways

Help this nonprofit clean up the city's rivers by digging in.

Each week, Pete Malinowski’s team picks up thousands of pounds of discarded oyster shells from more than 70 New York City restaurants, including seafood favorites like Oceana and celebrity chef Jonathan Waxman’s JAMS in the 1 Hotel Central Park. The shells don’t exactly smell nice, and plenty of them still need to be properly cleaned. It’s a dirty job, but it’s all worth it.

Malinowski is determined to rebuild New York Harbor and clean up the city’s rivers, even if it takes one billion oysters.

“We are making progress toward restoring a lost habitat and motivating a generation of New Yorkers to care about and care for the ecosystem around them,” says Malinowski, who founded the aptly named Billion Oyster Project in 2014 to repopulate the city’s oyster reefs. “Just one shell can be the home for up to 20 oysters in our hatchery.”

When Henry Hudson landed in the 1600s in what is modern-day New York City, the waterways around the area were covered in oyster reefs. Fish populations flourished, and the water was so clean that a massive fishing industry exploded. Fast-forward about 10 generations: The reefs have been virtually extinct for more than a century, and the murky waters garner many a comedic jabs from locals. Nitrogen buildup from agricultural pollution and rainwater runoff has caused a lack of oxygen in the waters surrounding the city, thereby killing any animal life, and overharvesting devastated the remaining population. While the harbor remains one of the busiest ports, you’re more likely to see a booze cruise circling Manhattan Island rather than a flotilla of fishing boats. Pose the idea of swimming in the Hudson River, and you’ll be looked at as if you have two heads.

Malinowski recognized this long before launching a nonprofit. Oysters, as well as other shellfish like clams, are superefficient filter feeders. They pump water through their bodies for food, and in the process they remove excess nitrogen from waters by incorporating it into their shells and tissue as they grow. It slowly cleans up the water, allowing for other live organisms to survive on the increased oxygen levels and, over time, hopefully rebuild an ecosystem.

More than 10 years ago, while teaching aquaculture at the New York Harbor School, Malinowski began having his students plant oysters as part of the curriculum. He and then program director Murray Fisher, who is now chairman of the board of the Billion Oyster Project, shared a passion for education through restoration. Not only did they notice how students changed their perspectives toward the environment of their own backyard, but the pair also saw how it made a measurable difference in the waterways. That’s when they decided it was time to launch something bigger, and the Billion Oyster Project was officially born.

The process of rebuilding the oyster population and increasing oxygen levels in polluted waters is not straightforward. Oysters cannot just be dumped into the waters with hopes for the best. Baby oysters spend their first few weeks as free-swimming larvae, but then they look for a hard substrate to which they can attach. That’s where the reefs come in. In order for their idea to succeed, Malinowski would have to add not only live oysters to the harbor but also reefs for them to live on. As it turns out, a discarded oyster shell makes the perfect substrate, rich in calcium carbonate, for baby oysters to make home.

“It’s incredibly difficult to find a bulk source of oyster shell in the Northeast,” explains Madeline Wachtel, deputy director of the Billion Oyster Project. She oversees the shell collection program, which reallocates approximately 385,000 pounds of would-be-discarded restaurant oyster shells from the landfill to the harbor. In fact, the program started after a suggestion from chef Ben Pollinger at Oceana. He offered to save his extra shells for the team if they picked them up; there is no way to utilize them after the plate returns to the kitchen. “Shells are highly valuable to restoration work but are currently treated as waste and shipped to distant landfills,” says Wachtel. “Our restaurant partnerships are now critical to our success.” Participating restaurants run the gamut from neighborhood spots like The East Pole and P.J. Clarke’s to the Michelin-ranked Gramercy Tavern and world-class hospitality brands like the Mandarin Oriental New York.

At JAMS, executive chef Ginger Pierce explained that they blow through about 200 oyster shells a day, which weekly amounts to 1,400 shells. The restaurant focuses on ways to drive down waste, from composting food waste to hosting an annual zero-waste dinner called A Supper That Sustains Us, which donates 100% of its proceeds. Part of that is an organic waste digester that sits in the corner of the kitchen, but oyster shells cannot be processed. It was heartbreaking to see them sent off in the dumpster. By partnering with the Billion Oyster Project, Pierce says, they can keep them out of landfills. It takes work on her end and, possibly more important, space for buckets of oyster shells to sit each week. But the tradeoffs are worth it to her team. “It’s pretty incredible,” she says of the nonprofit. “They are offsetting waste by giving something that would otherwise be discarded a second life. They are helping to make our bays and oceans cleaner through natural filtration. And they are educating young people.”

In its first five years, the nonprofit has restored 28 million oysters across 12 reef sites in New York Harbor. That includes reclaiming 1.3 million pounds of oyster shell to build the reefs, managing a team of nearly 9,000 volunteers, collaborating with local schools, and overseeing a processing facility on Governors Island.

It’s all reducing nitrogen in the local waters in a measurable way—72,500 pounds in total, to be exact. The team regularly tests the waters and has consistently seen that oysters reduce local nitrogen levels around the reefs by 21% in the course of 60 minutes. Water continuously flows in and out, so there is always more nitrogen to be removed. Additionally, they monitor the biodiversity of the reefs and have seen an increase in the number and types of animals—everything from worms and anemones to large fish—present after a reef is installed.

Malinowski is quick to point out that oysters won’t entirely resolve the issues in the harbor but do make steps toward success. “Harbor-wide nitrogen is a much larger issue that will be solved by upstream solutions, like removing the inputs,” says Malinowski. Untreated wastewater from New York City, pollution from rainfall, and, of course, legal restrictions have all posed challenges for the project as well. “Building reefs requires permission from several local, state, and federal agencies,” he adds. “These permits are not only challenging to obtain but require us to reduce the scale of our installations.”

The nonprofit does take its mission beyond its hands-on work on the water. It is currently advocating for a bill in the Ways and Means Committee of the Assembly that would give a tax credit of $0.10 a pound to restaurants and organizations that donate oyster shells. Currently there is no tax incentive for the businesses involved in the shell collection program—it’s all done out of the kindness of their heart and desire to be part of a closed-loop system that benefits the health of their own backyard.

Further, Malinowski continues to educate. He partners with other organizations working in the harbor, including the NYC Parks Department, Bronx River Alliance, and the New York/New Jersey Baykeeper as well as the city’s public schools. “We want learning about the harbor and oyster restoration to be a reality for the 1.1 million public school students in NYC,” he says. “We hope to be working with 200 schools by 2024.”

As for those billion oysters? That’s likely a few decades in the future, but Malinoski remains committed. If, annually, his group can restore 25 million oysters on five acres of reef, plus make improvements to breeding with a state-of-the-art hatchery and restoration facility, he believes they will be capable of reaching that scale. The organization’s goal, after all, states that “by 2035, one billion live oysters will be distributed around 100 acres of reefs, making the harbor once again the most productive waterbody in the North Atlantic.”

Consumers can help too. Simply eat oysters at partner restaurants, and you’ll know those discarded shells are gaining a second life. In the future, Malinowski notes, New York City just may be the oyster capital of the world.

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