Lock and Dam No. 5 (Upper Mississippi River)

Lock and Dam No. 5 (Upper Mississippi River)
Name	Lock and Dam No. 5
Location	Minnesota–Wisconsin, Upper Mississippi River
Built	1930s–1940s
Architect	United States Army Corps of Engineers
Governing body	United States Army Corps of Engineers

Lock and Dam No. 5 (Upper Mississippi River) is a 20th‑century navigation facility on the Upper Mississippi River between Minnesota and Wisconsin. Constructed under the direction of the United States Army Corps of Engineers as part of a system of locks and dams, it regulates pool levels, supports commercial navigation, and influences regional riverine ecology. Situated near communities such as La Crescent, Minnesota and La Crosse, Wisconsin, the project intersects transportation, flood control, and recreation networks.

History

Planning for the project followed authorization tied to the Rivers and Harbors Act and post‑World War I river improvement programs that involved the United States Army Corps of Engineers and congressional committees from Minnesota and Wisconsin. Construction phases occurred during the 1930s and 1940s, contemporaneous with other projects like Lock and Dam No. 4 (Upper Mississippi River) and Lock and Dam No. 6 (Upper Mississippi River), and were influenced by federal initiatives associated with the New Deal and infrastructure priorities after the Great Depression. Local stakeholders from La Crosse, Wisconsin, Winona, Minnesota, and adjacent counties engaged with state legislators and the United States Congress concerning funding and land acquisition. Over decades, the facility has undergone periodic rehabilitation overseen by the Mississippi Valley Division of the United States Army Corps of Engineers and coordinated with agencies such as the U.S. Fish and Wildlife Service and the Minnesota Department of Natural Resources.

Design and Construction

The design reflects engineering practices employed by the United States Army Corps of Engineers for navigation dams, drawing on precedents set at projects like Keokuk Lock and Dam and designs reviewed by the American Society of Civil Engineers. Primary construction materials included concrete and steel supplied through industrial networks tied to Midwestern United States manufacturing centers. Equipment and techniques from companies serving projects across the Mississippi River corridor—similar to contractors used on the Upper Mississippi River National Wildlife and Fish Refuge projects—were utilized. Construction logistics involved riverine cofferdams, diversion works, and placement of movable gates; workforce mobilization paralleled New Deal era employment patterns that also manifested at infrastructure projects in Illinois and Iowa.

Structure and Operations

The facility comprises a navigational lock chamber and a movable dam section with gates designed to control upstream pool elevations consistent with the 9‑foot navigation channel policy established by federal statutes. Operations are managed by the United States Army Corps of Engineers district office responsible for the Upper Mississippi River; lockage schedules accommodate towboats and barge tows serving inland ports such as St. Louis, Missouri and Minneapolis, Minnesota. Maintenance activities include chamber dredging, mechanical gate repair, and concrete rehabilitation coordinated with agencies like the Environmental Protection Agency when hazardous materials handling is required. The lock’s operating regime is integrated with adjacent projects such as Lock and Dam No. 5A (Upper Mississippi River) and forms part of the navigation system stretching between Minnesota and the Gulf of Mexico shipping network.

Environmental and Ecological Impact

The impoundment created upstream pools altered hydrology and habitat, affecting species and ecosystems monitored by the U.S. Fish and Wildlife Service, the Minnesota Department of Natural Resources, and the Wisconsin Department of Natural Resources. Changes in flow regimes influenced wetlands and floodplain forests in the Upper Mississippi River National Wildlife and Fish Refuge, with implications for migratory birds like species tracked by the Audubon Society and fish communities studied by researchers at institutions such as the University of Minnesota and University of Wisconsin–La Crosse. Mitigation and research programs have involved partnerships with the River Studies Center and federal programs addressing invasive species such as Zebra mussel and Asian carp. Environmental reviews and adaptive management efforts reference statutes including provisions of the Clean Water Act and coordination under interagency frameworks involving the National Marine Fisheries Service.

Navigation and Transportation

Lock and Dam No. 5 supports the nine‑foot channel project that underpins commercial navigation linking inland terminals at La Crosse, Wisconsin and Red Wing, Minnesota with the broader Mississippi River inland waterway system. Traffic includes agricultural commodities originating in Iowa and Minnesota bound for export terminals accessed through St. Louis, Missouri and New Orleans, Louisiana. Coordination with towing companies, barge lines, and port authorities such as the Port of La Crosse informs lockage priorities during peak seasons for grain shipments and aggregate movements. Events affecting navigation—ice, flood stages influenced by the Missouri River or Ohio River systems, and maintenance closures—are managed through notices to mariners issued by the United States Coast Guard and the United States Army Corps of Engineers.

Recreation and Local Economy

The lock and associated pools provide boating, fishing, and birdwatching opportunities that bolster tourism economies in La Crescent, Minnesota, La Crosse, Wisconsin, and nearby river towns. Anglers target species documented by state agencies and academic studies, attracting outfitting services and charter operations similar to those supporting recreation on the Mississippi River corridor. Riverfront parks, marinas, and trails connect to regional attractions such as the Great River Road and support hospitality sectors including inns, restaurants, and outdoor recreation businesses. Economic assessments by regional planning commissions and university extension services evaluate the facility’s role in sustaining jobs in navigation, recreation, and resource management.

Category:Upper Mississippi River locks and dams Category:Buildings and structures in Minnesota Category:Buildings and structures in Wisconsin