Under the Flood Control Act of 1944, the United States Congress authorized construction of a dam on the Genesee River to protect the lower Genesee River Valley and Rochester metropolitan area from flooding. To build Mount Morris Dam, five contractors from across the country joined together as the Mount Morris Dam Builders: Arundel Corporation of Baltimore, Maryland; Hunkin-Conkey Construction Co. of Cleveland, Ohio; J.C. Maguire of Los Angeles, California; L.E. Dixon Co. of San Gabriel, California; and Shofner, Gordon and Hinman of Los Angeles, California. Work began in March 1948 and was completed four years later in May 1952, with typically more than 400 people on the site at one time, including surveyors, operating engineers, laborers, carpenters, iron workers, electricians, masons, inspectors, and office workers. The dam stands as the product of the perseverance and dedication of the men and women who worked long, arduous hours to complete it, and after 50 years it still remained the tallest concrete gravity dry dam east of the Mississippi River. In its first 50 years, Mount Morris Dam prevented almost $1 billion in flood damage.
