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Thomas J. O'Brien Lock and Controlling Works, Illinois Waterway, Illinois (Major Rehabilitation/Major Maintenance)

Published March 11, 2020

Entrance to Lake Michigan (River Mile 326.0), in Chicago, Illinois

The T.J. O’Brien Lock and Controlling Works is an aging structure which is at an increasing risk of failure. A component failure of the aging lock structure, mechanical equipment or electrical distribution system would result in an unscheduled lock closure causing significant navigation traffic delays on the waterway for traffic entering and exiting Lake Michigan. The project 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, Illinois, 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 1000 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. The controlling segment, a reinforced concrete structure with four slide gate sections, is 53 feet in length. Significant features of the work include rehabilitation of the sector gate electric system, the lock electrical distribution system and injection grouting of the lock land & river walls cells.

The existing lock mechanical and electrical systems are original equipment installed in the 1960s. An electrical component failure of the lock electrical distribution system or the sector gate electrical system could result in lock failure, which could cause delays to navigation traffic. The sheet piling for the lock land wall and river walls have also been in service since the original construction of the lock. 

T. J. O’Brien Lock and Controlling Works were placed into operation in 1960. After over 50 years of service reliability and operation, problems are a recurring challenge and have significant impacts to the navigation users. T. J. O’Brien Lock and Controlling Works is the only commercial access from the Illinois Waterway to Lake Michigan.
The completed Rehabilitation Evaluation Report was approved in 2005. The project is currently awaiting a new start and funding.

Additional Information

Congressional Interest

Senators: Richard Durbin (IL), Tammy Duckworth (IL)

Representative: IL-11 (Bill Foster), IL-2 (Robin Kelly), IL-3 (Dan Lipinski)

CG - Construction General
River and Harbor Act of 1930

Summarized Project Costs

Estimated Federal Cost    $55,700,000
Estimated Non-Federal Cost  $26.500.000 
Estimated Total Project Cost  $82,200,000 
Allocations Prior to FY 2020  $0
FY 2020 Allocation   $0
FY 2020 Total Capability   $2,000,000


Major Work Item Current Year
FY 2020: Work is on hold awaiting funding.  If funded, plans and specification for Major Rehabilitation / Major Maintenance of the facility would be initiated