T.J. O'Brien Lock

Chicago District
Published Jan. 9, 2024

Additional details can be found at

Additional details can be found at

Project Description and Background

The T.J. O’Brien Lock and Controlling Works is located at the entrance to Lake Michigan (River Mile 326.0), Calumet River, in Chicago, Illinois. The facility is a unit of the Inland Waterway Navigation System and is one of nine such facilities between Chicago and Versailles, Illinois.

O'Brien Lock is a low lift sector gate lock. It provides a maximum lift of 5.0 feet for traffic passing from Lake Michigan to the Little Calumet River. The lock chamber is 1,000 feet long by 110 feet wide. The adjacent dam is 257 feet in length and comprised of two sections. The fixed section is 204 feet of steel sheet pile cellular construction.

T.J. O'Brien Lock and Controlling Works were placed into operation in 1960. After more than 60 years of service, reliability of operations is a recurring challenge posing significant risks to navigation users of the Illinois Waterway. A Major Rehabilitation Evaluation Report was approved in 2005. The Bipartisan Infrastructure Law (BIL) provided funding for major rehab (FY22 CG) and major maintenance (FY23 O&M) activities.

Current Status

Site investigations are underway by an A-E contractor.  Results of the investigations will inform future activities, including a design charrette and value engineering meeting in Winter 2023 to determine the best course of action for the TJO Lock Rehab.

Scour protection design efforts are underway, with a contract award scheduled for 2QFY24.

Project Authorization

Rivers and Harbors Acts of 1927 & 1930