Illinois Waterway, Thomas J. O'Brien Lock and Control Works, East 130th Street, Chicago, Cook County, IL

Significance: The Thomas J. O'Brien Lock and Control Works is significant as a component of the Illinois Waterway, a navigable route linking Lake Michigan with the Mississippi River and beyond. The lock and control works are located on the Calumet-Sag Channel, an artificial channel that connects the Little Calumet River with the Chicago Sanitary and Ship Canal. The Army Corps designed the Thomas J. O'Brien lock (in operation in 1965) to accommodate the longer barge tow configurations in use on the waterway. The lock is significant for its use of sector gates as the Army Corps experimented with a new gate type to reduce construction costs and accommodate the particular conditions at the site.
Survey number: HAER IL-164-I
Building/structure dates: 1957-1960 Initial Construction