For over 150 years, the Waverly Dam has been integral to the city. The Cedar River's value to industrial and economic development led to extensive development on the adjacent floodplain, and the risk of flooding in Waverly increased significantly with the 1915 construction of the new concrete dam and elevated spillway. Memorable floods occurred in 1917, 1933, 1945, 1948, 1961, 1965 twice, and 1993 twice. A 100-year flood hit in 1999 and a 500-year flood struck in 2008. A flood protection study provided by Stanley Consultants in 2000 recommended an inflatable dam to protect the city from future flooding, but funding was not secured until the catastrophic 500-year flood of 2008 brought immense destruction to the town of 10,000. Waverly's new inflatable dam is fully automatic with a gated spillway that maintains a set water level elevation and automatically adjusts to flow rates. Hinged crest gates that control discharge and pool level run the length of the former uncontrolled spillway. Rather than alter the floodplain with levees to contain the river, the project altered the river to fit the floodplain, lowering the river's flood profile, reducing the extent of the floodplain, and removing the floodplain from properties. The new dam now protects 450 homes and businesses from a 100-year flood, preserves hydroelectric generation at the oldest operating facility in Iowa, and enhances recreational opportunities by maintaining the upstream pool elevation.