When did the Gavins Point Dam get damaged?
Gavins Point Dam:  During the 2011 Missouri River Flood the dam was damaged by debris and a significant portion of rocks were dislodged from its upstream side. 2011 Missouri River Flood: The 2011 Missouri River floods was a flooding event on the Missouri River in the United States. 2011 Missouri River Flood:  All six major dams along the Missouri River released record amounts of water to prevent overflow which led to flooding threatening several towns and cities along the river from Montana to Missouri; in particular Bismarck, North Dakota; Pierre, South Dakota; Dakota Dunes, South Dakota; South Sioux City, Nebraska, Sioux City, Iowa; Omaha, Nebraska; Council Bluffs, Iowa; Kansas City, Missouri; Jefferson City, Missouri, as well as putting many smaller towns at risk.
The 2011 Missouri River floods