The Peoria Lock & Dam is the second Lock & Dam structure on the Illinois Waterway when heading upstream from the Mississippi River. Like the LaGrange Lock & Dam, it has a 10 foot head (waterfall), and uses the wicket style of gate. With wickets, the entire dam is built on a hinge. During high water, the wickets are down, and the river traffic uses the main river channel. During low water, the wickets are raised, creating a pool behind the dam, and navigation traffic has to use the lock. The lock is the standard upper river size of 110 feet wide by 600 feet long. A single Tainter gate was installed to make fine control over the pool heights possible.

The US Army Corps of Engineers submitted a permit request in 2003 to add a hydro generator to this project. The generator would consist of 4 tubular shaped turbines that could be lowered in the water to produce electrical power. This would be a run of the river project in that there would be no storage pond behind the dam. The result is that power generation would depend on how much water was available at a given moment.

Unlike the Mississippi River Lock & Dam structures, the Peoria Lock & Dam is closed to the general public since 9/11 due to security concerns.