The Soo Locks facility, operated and maintained by the U.S. Army Corps of Engineers, Detroit District, is the district’s largest project and is located on the St. Marys River at Sault Ste. Marie, Michigan along the Canadian border. Approximately 80 million tons of commercial commodities pass through the Soo Locks every year. The New Lock at the Soo is being built in the footprint of the existing Sabin Lock, the northern most lock of the four on the Soo Locks facility, opened in 1919. The construction program, which includes improvements to the northern approach channel, is occurring in three phases of work.