The program area comprises the Upper Mississippi River System, as defined by Congress in the Water Resources Development Act of 1986, which includes the Upper Mississippi River from Minneapolis, Minnesota, to Cairo, Illinois; the Illinois Waterway from Chicago to Grafton, Illinois; and navigable portions of the Minnesota, St. Croix, Black and Kaskaskia Rivers.

This multi-use resource supports an extensive navigation system (made up of 1200 miles of 9 foot channel and 37 lock and dam sites), a diverse ecosystem (2.7 million acres of habitat supporting hundreds of fish and wildlife species), floodplain agriculture, recreation, and tourism. Based on the recommendation of the recently completed UMR-IWW System Navigation Feasibility Study that examined system needs over the next 50 years, the Navigation and Ecosystem Sustainability Program was implemented to achieve the dual purposes of UMRS ecosystem restoration and navigation improvements. The Lock 25 – New 1200 ft. Lock is one of 7 new 1200 ft. Lock Projects being implemented under this program.

Lock and Dam 25: New 1200-ft Lock

Lock and Dam 25 is located in Calhoun County, Illinois, and Lincoln County, Missouri, at approximately Mile 241.4 on the Upper Mississippi River above the mouth of the Ohio River near Winfield, Missouri.   

Proposed project features include construction of new 1200-foot, pile founded, lock located in the auxiliary miter gate bay, and construction of an upstream, ported guard wall totaling 1200 feet, and a 650-foot downstream approach wall. The existing 600-foot lock remains in place and will become auxiliary lock chamber to be used primarily by recreation traffic. The project also includes associated channel work, relocations and site-specific environmental mitigation. 

The majority of the Upper Mississippi River locks were designed and constructed in the 1930’s and the lock chambers are 600-ft. long. The 600-ft. lock chamber cause significant average delays to navigation because of double lockages required for tows larger than 600-ft.The new1200-foot lock will significantly reduce delays and increase safety.

The combination of ecosystem and navigation in a single U.S. Army Corps of Engineers program required many years of coordination with both the navigation and ecosystem partners and it will alter the future of the Upper Mississippi River System to ensure it remains the vital transportation and ecosystem corridor for the next 100 plus years.