Lock and Dam 25, located in Winfield, Missouri, is a 1,296-foot long dam structure equipped with a single 600-foot lock chamber, three submersible roller gates (near the center of the structure, see image at right) and 14 submersible tainter gates. At the time of construction, the submersible gates represented a marked advance in gate design and were seen as an improvement over non-submersible gates because they allowed for the almost unobstructed flow of floodwaters, ice and debris. This lock opened on May 18, 1939.

Lock 25 is preparing for major construction that will include a new 1200-foot, pile founded lock located in the auxiliary miter gate bay, and construction of an upstream, ported guide wall totaling 1200 feet, and a 650-foot downstream approach wall.