The Peoria Lock and Dam, a historic lock and dam complex on the Illinois River at Creve Coeur, was built in 1938 and 1939 as part of an effort to make the river navigable and establish a route for barges between Chicago and the Mississippi River.
After the Supreme Court’s 1930 decree limiting the diversion of water from Lake Michigan, a new navigation plan was developed calling for the removal of four old locks and dams at Henry, Copperas Creek, LaGrange and Kampsville; new locks at Peoria and LaGrange; and a dam on the Mississippi River at Alton, Missouri. The lock is used only during low and moderate river flows when the wicket dams are raised to maintain the nine-foot navigation depth. During high flows, the wickets are lowered and open river conditions prevail.
Peoria is one of only two wicket dams on the Illinois Waterway. It was added to the National Register of Historic Places in 2004, along with the seven other lock and dam sites on the Illinois Waterway. iBi
Source: U.S. Army Corps of Engineers