Lock and Dam No. 3 is a lock and dam located near Red Wing, Minnesota on the Upper Mississippi River around river mile 796.9. It was constructed and placed in operation July 1938. The site underwent major rehabilitation from 1988 through 1991. The dam is 365 feet (111.3 m) long with 4 roller gates. More than 2,000 feet (609.6 m) of earth embankment with a series of upstream spot dikes completes the structure to create Pool 3. The lock chamber is 110 feet (33.5 m) wide by 600 feet (182.9 m) long. The lock and dam is owned and operated by the St. Paul District of the United States Army Corps of Engineers-Mississippi Valley Division.