"New York Waterfall" installation under the Brooklyn Bridge by artist Olafur Eliasson in 2008.
New York City Waterfalls was a public art project by artist Olafur Eliasson, in collaboration with the Public Art Fund, consisting of four man-made waterfalls placed around New York City along the East River. At $15.5 million, it was the most expensive public arts project since Christo and Jeanne-Claude’s installation of The Gates in Central Park. The waterfalls officially began flowing on June 26, 2008 and they ran from 7 am to 10 pm (under illumination after sunset), until October 13, 2008. (wiki)