New York City
Plus Pool is hell-bent on situating a floating pool in the turbulent waters of the East River
A 320-ton pilot structure arrived in New York city waters this week. The myriad engineering challenges are raising questions over $16 million in public funding.
Plus Pool’s pilot pool was transferred from land to the water at Port Newark Plus Pool
It’s a beautiful vision for a city surrounded by water: On a sweltering day in New York, you emerge from the concrete canyons of Manhattan, reach the vast East River and dive in without a second thought.
What seemed like fantasy took a step toward reality when a massive steel shell arrived from Mississippi in early July. On Wednesday, the 320-ton structure was lifted off of a barge and lowered into the water at Port Newark in New Jersey. All 2000 square feet of it was then towed to the Reicon Group shipyard in Staten Island where it’ll be fitted out with a pool, pumps, filtration systems and other structural elements.
The operation is called Plus Pool, the brainchild of a group of architects and swimming enthusiasts who envision a huge floating pool plopped directly into the East River near the Lower East Side. The idea was first tossed around in 2010, and a kickstarter campaign was born. The nonprofit “+Pool” was then launched in 2015, named for the four joined sections that will form the shape of a plus sign. The vision is to fill it with river water, which will be filtered through the pool structure itself. Next year, the pilot pool will serve as a test platform in the East River. The organization hopes to have the full size plus-shaped pool built and operational by the summer of 2027. Earlier target dates came and went as they worked with state and city agencies to develop protocols for permitting the first-of-its-kind floating river pool. So far, the project has raised $6.5 million in private funds, and it netted $16 million in public funding: $12 million from the governor and another $4 million from City Hall.
Plus Pool is undoubtedly visionary. If it’s successful, it will pioneer new technology and redefine how New Yorkers interact with the river. But situating a massive floating pool in a waterway that has dramatic tidal shifts, sometimes freezes, and can be rocked by nor’easters annually and boat traffic daily comes with massive challenges. With many of the city’s existing pools in dire need of capital funds, the flow of public money into a project with an uncertain future raised some eyebrows.
Some public policy experts aren’t so sure the project is worth the investment. “ It's great to experiment with the technology that can turn saline, dirty river water into clean swimming water,” said former New York City Parks Commissioner Adrian Benepe. But he pointed to the tremendous demand for pools on land, especially in areas that have historically been shortchanged with public amenities. “ There are many neighborhoods in New York City that lack swimming pools, and they're expensive, but it's better to spend the money on year-round pools and not to build pools that have only a two- to three-month lifespan each year,” Benepe said.
“One of the most complex environments”
Despite its name, the East River is actually a tidal straight. The flow changes direction four times a day. It’s notorious for “strong currents and significant tidal swings, sometimes up to six or seven feet,” according to Indigo River CEO Dena Prastos, whose team of architects and civil engineers helped Plus Pool get through the permitting process. Designs also had to take into account the impact of wakes from boat traffic and storm surges that affect how the pool is kept stable. “The East River presents one of the most complex environments for a project like this,” Prastos said.
Plus Pool would be held in place by tall, wide steel pilings driven into the riverbed, similar to how floating ferry landings are anchored in the East River. The pool would slide up and down on the pilings as the tides rise and fall. The state Department of Environmental Conservation has strict regulations governing a fixed object on the surface of a waterway, though, and the potential impact to aquatic ecosystems below. There are questions about how a lack of direct sunlight would affect the area directly below Plus Pool.
“ The pilot is really to test how these concepts perform under real conditions, not only structurally, but environmentally and operationally,” Prastos said.
The changing seasons also pose challenges for the short and long-term operation of a giant floating pool. Ice sheets are not uncommon in the river during harsh winters. Water expands when it freezes and can cause pipes to burst if they’re not drained. Even so, the dreamers behind Plus Pool see winter as an opportunity rather than an obstacle.
“ Maybe we do have it open in the winter for a cold plunge sauna situation,” said Kara Meyer, managing director of Plus Pool. “And that generates some revenue to operate it free during the summer months for the public.”
But the primary challenge for the pool will be the water that fills it.
Recent regulatory changes make it possible for anyone to propose an enclosed swim area in sections of the river and seek permits. But an open swim area, a place where people could walk or jump into the river, would require constant water quality monitoring and frequent closures after rainy days, when untreated waste from sewer runoff causes a rise in harmful bacteria levels.
Some other cities around the world managed to clean up once polluted urban waterways and open them for swimming, including Paris, Copenhagen, Oslo, Rotterdam and Amsterdam. People dive directly into rivers and canals from esplanades and piers. In all of those cities, water quality is closely monitored and an increase in hazardous bacteria levels causes a temporary closure.
The people behind Plus Pool believe they can keep the pool open even when water quality is bad by pumping river water through a filtration system and passing it through ultraviolet light for disinfection. This type of water disinfection is not new. “It's used in drinking water treatment plants a lot,” said Linda Weaver, an expert on water purification who serves as a professor of civil and environmental engineering at Ohio State University. “It's a tried and true technology.”
But filtering the water through a pool structure itself would be new, and it’s an engineering feat. “ Until it's there for a long time and we understand over that duration how it's performing, it's really hard to predict,” Prastos said. The Plus Pool filtration process is designed to also push water through membranes that block debris and even some bacteria from getting through. Those filters would require a lot of maintenance, Weaver said. “ The piece that you need to do is clean them quite regularly.”
In a traditional pool, chlorine addresses sanitary issues that come up when people are in the water for long periods. Instead of using chlorine, Plus Pool’s system is designed to continually flush out old water and bring in fresh water. It’ll be a different experience for swimmers accustomed to chlorinated pools. According to Weaver, the water may have a yellowish hue.
Moving heaven and earth
Total cost for the construction, operation and permitting of the pool is impossible to pin down at this point. The plan’s backers say the price tag is dependent on what they learn from testing, as well as health and environmental requirements yet to be developed by state agencies. Ultimately, the nonprofit hopes to work with one or more partners who would help to launch the pool and support its operations for at least the first five years, while keeping it free to the public in summer months.
"As philanthropy should drive transformation and innovation, Plus Pool is to be commended, particularly its focus on swimming safety,” said Chris Ward, CEO and interim president of the Waterfront Alliance. “But $16 million of public funding when existing city pools are closed or failing raises serious questions about priorities."
Benepe praised Plus Pool for its mission and advances but questioned the long-term viability for the floating pool. “ In a perfect world, you'd have money for everything. But there isn't unlimited funding. So, even if this experiment were successful, it’s a very difficult and expensive model to replicate,” Benepe said.
Gov. Kathy Hochul’s office defended the funding in a written statement, calling Plus Pool “an innovative way to provide families with safe spaces to swim in New York City” and emphasized its place within the broader NY SWIMS program, a $60 million investment in swimming and pools across the state. Mayor Eric Adams’ office said that the city’s $4 million grant was issued in coordination with the governor “to launch +Pool, an innovative facility that will address equity access gaps and allow New Yorkers of all backgrounds to stay cool and have fun.”
The people championing the project succeeded in changing the conversation around public access to New York’s waterways. They’ve also pushed some notoriously recalcitrant public agencies to consider evolving longstanding policies.
Why would you swim in the East River?
Floating river pools were common in the city during the early 20th Century, but pollution forced their closure in 1938. Decades of dumping waste into city waterways made the idea of contact with river water more nauseating than nostalgic. That began to change after the Clean Water Act of 1972. Since then, water quality has improved dramatically. On most days, a swim in the East River wouldn’t leave you sick, as long as it hasn’t rained recently. But officially, swimming has remained off-limits.
“ We wanted to reconnect New Yorkers to their waters,” Meyer said. The nonprofit also supports swim instruction programs and advocates for increasing public swimming opportunities as climate change raises average summer temperatures in the city.
Meyer said the public investment in Plus Pool already paid dividends for New Yorkers in the form of regulatory changes that are opening up waterways for more types of use.
The state Department of Environmental Conservation amended rules around water-quality standards in 2023. Long stretches of waterfront were reclassified, some strict restrictions were removed and more areas were designated safe for swimming. Additional regulatory changes are coming.
“It's really game-changing for New York,” said Meyer. She pointed to new opportunities for waterfront communities to apply for permits to create swimming access. Meyer said the concept is being “ assessed, evaluated, developed and proven here,” and if successful, it could be replicated not just across New York but also in other cities. “ We can't advance this innovation without a partnership because it just requires the city and state.”
There isn’t a well-established regulatory framework for approving a massive floating pool structure anchored next to the Lower East Side. Plus Pool has to navigate a convoluted permitting process involving several city and state agencies including the Department of Health and Mental Hygiene, Small Business Services and the Department of Environmental Protection, as well as the state’s Department of Environmental Conservation and Health Department, the Coast Guard and the Army Corps of Engineers.
For now, the larger, complete Plus Pool design remains aspirational. No additional public funds have been committed to the project. The plan calls for evaluation and assessment of information gathered during the pilot testing in the summer of 2026. Until then, many people will be watching to see whether this pilot sinks, swims, or something in between.