What tunnel runs under the Hudson River and has a ventilation system innovated by Ole Knutsen Singstad?
Ole Singstad Ole Knutsen Singstad (June 29, 1882 – December 8, 1969) was a Norwegian-American civil engineer who innovated the ventilation system for the Holland Tunnel (which subsequently became commonly used in other automotive tunnels) and advanced the use of the "Sunk-tube" method of underwater vehicular tunnel building, a system of constructing the tunnels with prefabricated sections.
63rd Street Tunnel The 63rd Street Tunnel carries the 63rd Street Line of the New York City Subway under the East River between the boroughs of Manhattan and Queens. , it is the newest of the East River tunnels, and the newest river crossing in the New York metropolitan area. Construction of the 63rd Street Tunnel began on November 24, 1969, and the tunnel was holed through beneath Roosevelt Island on October 10, 1972. However, completion of the tunnel and its connections was delayed by New York City's fiscal crisis of the 1970s and it was not used in revenue service until 1989.