New York City open water swimmers circumnavigated Manhattan in an eight-hour, 29-mile relay swim, highlighting decades of water quality improvements in local waterways despite ongoing warnings from municipal health officials regarding urban swimming safety.
Manhattan Circumnavigation Highlights Improving Harbor Conditions
The open water swim began at Pier 25 when four swimmers boarded the motor boat Melissa Marie under cloudy skies, according to participant Derek Yach. Yach, a cancer survivor who initiated the swim as a fundraiser for cancer treatment equipment in Kenya, stated that seeing the sights of Manhattan from the water was spectacular. Just over eight hours later, the relay team crossed the finish line at a tall wooden piling near Battery Park. Deanne Draeger, cofounder of URBANSWIM, an organization that coordinated swims for nearly 200 people in the harbor, stated that the waterways belong to all of us and that the water should not be just a view. According to data cited by the city’s Department of Environmental Protection, bacteria in water samples across the Hudson and East rivers test well within state standards for swimming, driven by river revitalization efforts ongoing since the 1970s.
Health Officials Urge Caution Despite Cleaner Waterways
City health officials maintain reservations about entering heavily trafficked urban waters. A spokesperson for the city’s Department of Health and Mental Hygiene recommended that New Yorkers celebrate improving water quality but swim at ocean beaches instead. Andrew Juhl, a biological oceanographer at Columbia University’s Lamont-Doherty Earth Observatory, explained that fecal indicator bacteria—found naturally in the guts of warm-blooded animals—indicate sewage contamination when present in open water. According to Juhl, major rainstorms trigger street runoff that overflows the city’s sewage system, sending untreated mixtures directly into the river at hundreds of discharge points. Juhl stated that swimming in sewage-contaminated water can cause nausea, diarrhea, ear infections, or rashes. While Juhl noted that water samples tested safe for swimming roughly 80% of the time during his 15 years working with Riverkeeper through 2022, Riverkeeper data showed pass rates dropping to about 60% between May 2025 and August.
Did you know? The Clean Water Act of 1972 established a regulatory framework for public waterways with the goal of making all waters clean enough to swim and fish in by 1983, a benchmark environmentalists argue should remain the standard for New York Harbor.
Historical Context of New York Harbor Clean-Up
New York Harbor is currently the cleanest it has been in more than a century, according to city data. John Waldman, a biology professor at Queens College who researches New York Harbor, recalled that 100 years ago the city sent raw, untreated sewage straight into riverways, creating 10-foot-deep patches of steaming sewage near outfalls. Waldman noted that he remembered driving down the FDR Drive in the 1970s and seeing turds in the water that would be a rarity today. This transformation was propelled by the Clean Water Act of 1972. However, environmental protections face ongoing policy shifts; earlier this month, the Trump administration moved to narrow the definition of “waters of the United States” to strip protections from natural water-filtering wetlands.
Logistical Safety Measures for Urban Open Water Swimmers
Swimming in New York Harbor requires strict safety protocols due to strong currents and commercial traffic. According to Riverkeeper, there are no public swimming access points in New York City, meaning jumps into the Hudson River require extensive logistical coordination. Draeger explained that URBANSWIM coordinates with the Coast Guard and the NYPD, deploys a trailing motor boat, assigns paddlers in neon kayaks to guide swimmers, requires neon swim caps for visibility, and stations safety coordinators to watch the river ahead. Draeger described this setup as a cocoon keeping the swimmer safe, warning that strong currents and tides can prove dangerous without proper understanding. Despite encountering occasional urban debris—including dead rats in the Harlem River, condoms locally known as “Coney Island whitefish,” and police investigations of dead bodies near Pier 25, as recalled by organizers—none of the participants in URBANSWIM events have reported falling ill.
Return of Marine Life to the Hudson River
Improving water health has coincided with a resurgence of marine life across the harbor. The return of animals demonstrates that investments in water treatment and management have increased the health of the marine ecosystem, according to a statement from the Department of Environmental Protection. Acoustic monitoring technology used by Whales of New York recorded two whale sightings in the area this month alone, and sightings of sea turtles, dolphins, and stingrays are possible. However, Juhl noted that marine life is less of a concern than human-powered water vehicles. URBANSWIM scheduled its final open water swim event of the season, featuring 30 participants swimming between the tip of Manhattan and the Statue of Liberty in remembrance of September 11.
Frequently Asked Questions
Is it legal to swim in the Hudson River in New York City?
While swimming is technically permitted in most parts of the Hudson River, there are no designated public swimming access points maintained by the city, according to Riverkeeper. Organized swims require extensive coordination with the Coast Guard and NYPD.
What causes high bacteria levels in New York Harbor?
According to Andrew Juhl of Columbia University, major rainstorms cause street runoff that overwhelms the city’s sewage system, resulting in sewage overflows directly into the rivers at hundreds of discharge points.
Have swimmers gotten sick during organized harbor swims?
Deanne Draeger of URBANSWIM and interviewed relay participants stated that none of the thousands of participants in the organization’s open water swims have reported falling ill.
How has the water quality changed over the decades?
According to city data and researchers like John Waldman, the harbor is the cleanest it has been in over a century, a major improvement from decades past when raw sewage was routinely dumped into the waterways prior to the Clean Water Act of 1972.
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