Construction of dam at Newburgh. According to the U.S. Army Corps of Engineers, construction on this dam began in June 1970 and was completed in 1975. The locks were built first, beginning in June 1966 and placed into operation in December 1969. Statistics on the dam: Type: Concrete fixed weir with tainter gate; Length: 2,275'; Upper pool: 358'; Lower pool: 342'; Number of gates: 9; Height of gates: 32'; Width of gates: 110'