Blogs > Water Quality > Event swimming returns to the Hudson

Event swimming returns to the Hudson

The Hudson River and its swimmers are back – reminding us of the need to improve water quality.

Research, including projects supported by Riverkeeper, has largely dispelled early concerns that SARS-CoV-2 might put swimmers at risk from exposure to sewage-contaminated water. More significantly, swim organizers are responding to the taming of the pandemic by vaccination, and the relative safety of outdoor activities. Several events are returning to the water, including the Great Hudson River Swim between Newburgh and Beacon. Several others, like the Hudson Crossing Triathlon, have been again postponed. And others are running at reduced capacity, including the 8 Bridges Hudson River Swim. [UPDATE:] Most recently, the New York City Triathlon had to cancel the swim portion of the July 11 event, due to high bacteria levels caused by sewage overflows.

Swimmers leap into the Hudson as part of the 8 Bridges Swim. (Photo courtesy Greg Porteus/Launch 5)

In all, event swimmers will be in the waters on 46 days between June 16 and October 11, 2021. Activities will take place across about 115 miles of water, from the Lower Bay of New York-New Jersey Harbor to the Rip Van Winkle Bridge, which spans the river between the City of Hudson and the Village of Catskill. These swimmers demonstrate the need to protect good water quality all the time, and along the entire length of the river.

Open water swimming became an Olympic event in 2008, influencing an international interest in the sport. The 28.5-mile marathon swim around Manhattan is part of the Triple Crown of Open Water Swimming, and the 8 Bridges Hudson River Swim is the longest open water swim event in the world. Both events draw international tourists to the region to take part, as does the New York City Triathlon.

Thus, it is not surprising that there is increasing interest in the use of the Hudson River and New York Harbor for open water swimming events. Data in the last decade suggests high popularity of swim events in these waters, with an average of 6,100 people participating in 25 events annually in the decade between 2010 and 2019, with a high of over 10,000 participants and 37 events.

There has been significant year-to-year variation in the number of events and number of participants overall. In 2020, the pandemic prevented virtually all event swimming. About 7 events facilitated 26 swimmers. The factors affecting this variation in other years is most strongly influenced by the choices made by event organizers, with some groups and events having started or ceased annual events in the last decade.

The other forces affecting this variation are related to weather, climate and water quality — key factors that are at the heart of Riverkeeper’s work. In 2019, for instance, the New York City Triathlon — typically the largest open water swim event each year, accounting for roughly half of all participants — was canceled due to extreme heat that put athletes at risk. In 2017 the Lady Liberty Sharkfest Swim was canceled due to rain-related water quality concerns, given the prodigious overflows of sewage that occur from New York City and several other river cities with combined sewer systems that are designed to overflow with street water and raw sewage.

These facts suggest that, while public bathing should be expected to increase as high temperatures prompt more people to seek out nearby waters to cool off, some event swimming may in fact be threatened by higher temperatures that put athletes at risk. For any swimming, the increases in extreme precipitation, coupled with aging and antiquated sewers, will mean that more swimmers are more likely to encounter water that is unfit for recreation — unless significant investments in fixing pipes and other infrastructure continues and grows.

Find the latest water quality data from Riverkeeper and our partners, showing whether the water at hundreds of locations in the Hudson River and its tributaries met EPA safe swimming criteria. Read water quality reports to make sense of our growing datasets, and take action on the most pressing issues affecting water quality, habitat and communities in the Hudson River watershed.

Hudson River Estuary swim events anticipated this year





Rip Van Winkle Bridge to Verrazzano Narrows Bridge

8 Bridges Hudson River Swim




Sleepy Hollow Sprint Triathlon and Relay



Around Manhattan

20 Bridges, 40 Bridges


June- October


Great Newburgh to Beacon Hudson River Swim




NYC Triathlon



Manhattan to Staten Island

Rose Pitonof Swim



Staten Island

Staten Island Triathlon



Statue of Liberty to Freedom Tower

Liberty to Freedom Swim



Coney Island

Triple Dip




Blog Posts in this Series:
Do people swim in the Hudson River? >
Climate extremes and beach closures on the Hudson >
Hudson River kayaking, SUPs and more on the rise >

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