Between 1843, when the first American establishments were opened in New York City, and 1860 at least 27 hydropathic treatment centers opened, two medical schools of hydropathy were established, several water cure journals were published, and over one hundred male and female practitioners provided therapy in the United States.
Image courtesy of Archive.org.
To learn more about the history of medicine and questionable cures, see Discovering Quacks, Utopias, and Cemeteries