The Red River had a history of seasonal flooding, aggravated by the broad ancient lake bed that formed the Red River Valley. The 1997 Red River flood caused extensive damage in the city. Fargo was upstream from the bulk of the flood waters that season, and Winnipeg had built an extensive system of flood control structures in the 1960s. In 1997, Grand Forks suffered the most damage of any major city in the Red River Valley. During the height of the flooding, a major fire destroyed 11 buildings in the downtown area. The government began developing a new levee system to protect the city, which was completed 10 years later. It required the relocation of numerous residents, as some neighborhoods were emptied for this construction.