Introduced in the early 1800s as a private diversion for the wealthy, by 1870 floating pools were being promoted as public baths to serve the city’s tenement districts. They consisted of pontoon-borne structures permanently moored to the land, with the river rising up through pine slats in the middle. This time around the pool is offering a much cleaner swim, a modern design, and a watery wanderlust.

The project is the brainchild of urban planner Ann Buttenwieser, who in 1999 founded the not-for-profit Neptune Foundation. “Our goal is to develop floating pools for the New York and New Jersey region, to be placed in areas where people are recreationally underserved,” she explains, noting that by making the pools nomadic, the benefits can be spread around. “One month it could be in the Bronx, the next it could be in Brooklyn, so it would be reaching a larger variety of people.”

To design the first facility, she recruited architect Jonathan Kirschenfeld. “I’m interested in the public realm and trying to build things that are part of the bigger city,” says Kirschenfeld, adding that the floating pool has become a personal pet project.

In 2004, they bought a 260-foot-long barge in Morgan City, Louisiana (“For the price of a studio apartment in Manhattan,” quips Kirschenfeld), and hired a shipyard to transform it. Now, the floating pavilion contains a 25-meter-long swimming pool and holds steel changing rooms and shower stations capped by colorful boxy roofs—an aesthetic that’s equal parts Mario Bellini and Super Mario Brothers. The barge made the journey to New York by tugboat last October and will be put through its first test runs this summer. The plan is to hand it over to the city’s parks department by 2008. “This is something for the people of New York,” says Buttenwieser. “It’s really going to be used, and I think it’s going to be wonderful.”