The U.S. Army Corps of Engineers (USACE) will conduct critical repairs to Lockport Lock and Dam requiring a scheduled closure of the lock chamber from March 31 through May 19, 2026. The closure’s primary objective is to replace the pintle sockets on the downstream miter gates. In service since 1986 without major repair, these assemblies function as the primary hinges for the 60-foot gates—the tallest on the Illinois Waterway. The replacement is critical as the gates must withstand the immense structural forces generated by Lockport’s 39-foot maximum lift.
The need for this repair was identified during a planned dewatering in 2025 for the installation of new upstream gates. During that project, inspection teams discovered cracks in the pintle sockets. As an interim measure, a carbon fiber-reinforced polymer wrap was engineered and applied to the gate hinges. This structural reinforcement has kept the gates safely operational for the past year while the new, more robust pintle sockets were designed and manufactured.
The upcoming closure will allow crews to install the permanent replacements and perform other key adjustments, including installing new quoin and miter blocks. These blocks are essential for ensuring the load from the water is properly transferred from the gates to the massive concrete lock walls.
“USACE is always aware that closures are not ideal for our navigation partners,” said Operations Manager and Chief of the Waterways Project Office, Michael Walsh. “However, this work is necessary to extend the life of the lock chamber. By scheduling this closure in advance, we’re ensuring our partners have the lead time they need to adjust, rather than forcing them to react to an unexpected outage.”
The repair work will be performed by the Rock Island District’s floating plant crew, utilizing assets and personnel from both the Illinois Waterway and Mississippi River Project Offices.
For over 90 years, the Lockport Lock and Dam has been an essential component of the Illinois Waterway’s 333-mile corridor. By bridging the Great Lakes and the Mississippi River, it enables a larger system that moves 630 million tons of cargo, generates $350 billion in economic output, supports 1 million jobs, and saves shippers an estimated $7 – 9 billion annually in transportation costs compared to moving the same tonnage by rail or truck.
The Chicago District is responsible for water resources development in the Chicago metropolitan area, upper Illinois River watershed, Lake Michigan watershed throughout Wisconsin, Illinois, and Indiana, and the upper Wabash River watershed in Indiana – an area of about 31,500 square miles. The district delivers vital engineering services through flood and coastal storm risk management, navigation, aquatic ecosystem restoration, regulatory, emergency management, recreation, and interagency support services.