The
Detroit Iron & Steel Co. brought ironmaking to Zug Island (and modern iron
smelting to the state of Michigan, which theretofore had only charcoal furnaces), with the construction of a
blast furnace in 1902. In 1904 the works was purchased by the
M.A. Hanna Company of Cleveland, Ohio, which built a second blast furnace in 1909. At this time the island's two furnaces were reportedly the largest of their kind in the world, producing
pig iron for
foundry companies. The plant expanded and became part of the Great Lakes Steel Corporation in 1931, becoming a key component of a fully integrated steel mill and a division of the larger
National Steel Corporation. A third blast furnace was added in early 1938 while the existing furnaces were rebuilt and enlarged. When National Steel became insolvent in 2003, most steel facilities and the rest of what is now called the Great Lakes Works, were purchased by
United States Steel, which currently operates the mill. The ironmaking facilities include 3 blast furnaces ("A", "B" and "D") and raw materials storage areas (the rest of the mill's facilities, primarily steelmaking and processing, are located at the main plant a few miles south in
Ecorse. Ships supply large ore docks along the north ("1 Dock") and east ("3 Dock") shores and large coal/
coke/ore storage fields along the south and west ("B Area") shores. Number 5 Coke Battery, once an integral part of the mill, is independently owned and operated by EES Coke LLC, a
DTE Energy company.
Delray Connecting Railroad, a subsidiary of Transtar, LLC, operates some rail facilities on the island. A "2-way" vehicle/rail bridge is the main access to the island. Secondary vehicle and rail bridges (the "Swing Bridge") at the southwestern corner of the island also allow mainland access. Iron produced at Zug Island is transported in
bottle cars via rail to steelmaking at the main plant while DTE's coke is shipped via rail to supply consumers, chiefly
ISG/
Mittal, in the merchant metallurgical market. During the industry's peak, thousands of workers were employed on the island with a large percentage of the downriver community supported by the local steel producer. Recently a few hundred people worked on the island with the hourly workers at U.S. Steel represented by
United Steelworkers Local 1299. U.S. Steel announced in December 2019 that it would idle most of its operations in the area, including all of its operations on Zug Island. Primary steelmaking activities shut down in April 2020, and the
hot strip mill shut down in June 2020; however in January 2021 the
Detroit Free Press reported that there remained 500 employees working at the plant, and that "a few operations [were] ongoing — as long as demand will support them". ==Wildlife==