Construction of Lock and Dam 16 was finished in 1937. The movable dam has 15 Tainter gates and four roller gates. The lock has a viewing platform that makes a great way to see the action of a towboat and barges locking through. It also provides a great place to view wildlife on the river, including Bald Eagles in winter and Double-crested Cormorants, Pelicans, and Great Blue Herons during summer. Tours are provided every Sunday at 2pm between Memorial Day and Labor Day weekends.