Located on Mississippi River mile 714.1 at Trempealeau, Wis. Constructed and placed in operation in June 1936. Last major rehabilitation from 1989-1999 Dam consists of 893 feet long concrete structure with five roller gates and 10 tainter gates. Earth embankment 2,600 feet long. Concrete overflow spillway 1,000 feet long. Lock is 110 feet wide by 600 feet long.