5 Nov 2025

Physical Modeling of Filling and Emptying (F&E) Systems of Proposed 1,200 ft Chambers at Locks 22 and 25: Hydraulic Model Investigation

Abstract: The US Army Corps of Engineers (USACE) is considering navigation improvements for several projects to meet predicted increases in tow traffic at the Lock and Dam 22 and Lock and Dam 25 sites in the Mississippi river. Some of these improvements include the addition or replacement of the navigation lock at the site. The following document contains the laboratory model investigations of the lock filling and emptying (F&E) system for additions at the sites. This report provides the results of research testing under the Navigation and Ecosystem Sustainability Program (NESP). The design guidance includes culvert geometry, port size, location, and spacing. Guidance for the lock chamber performance, based on acceptable filling and emptying operations is also included. The results show that the original design is a feasible design based on the hydraulic performance of the system as a result of the experimental tests. Further discussions with the St. Louis District (CEMVS) arrived at a new culvert to port transition design that was more in line with the existing geometry at Lock and Dam 25. The new design and port spacing configuration were agreed by CEMVS and ERDC to not have significant impact on hawser forces or the overall chamber performance.