Mississippi Lock and Dam No. 4
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Lock and Dam No. 4
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Lock and Dam No. 4 and viewing platform
 
Attraction
Description
Located on Mississippi River mile 752.8 in Alma, Wisconsin, Lock and Dam No. 4 was constructed and placed in operation in May, 1935. The dam consists of a concrete structure 367 feet long with six roller gates and 22 tainter gates. The earth embankment 5,400 feet long. The lock is 110 feet wide by 600 feet long. The lock is on the Wisconsin side of the river with an overlook to watch boats locking through. Interpretive signage describes how the navigational locks on the Mississippi work.
 
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