The environmental organization Urban Divers boat tour of the polluted inland waterway, the Gowanus Canal. The Urban divers is a non-profit organization that monitors the NY/NJ Harbor Estuary and offers programs to raise the public awareness of New York's waterways. The Gowanus Canal, which was completed in the late 1860's to facilitate industry along it's banks, became increasingly polluted until a pumping station was constructed at one end in the early 20th century to 'flush' out the canal. In