2011 Red River Flood, North Dakota, Minnesota, United States

Background
• Geology
The Red River flows from the United States into Lake Winnipeg in Manitoba, Canada. Unlike the vast majority of rivers in the United States, it flows northward, which means melting snow and river ice, as well as runoff from its tributaries, often create ice dams, which cause the river to overflow. The valley is essentially flat, leading to overland flooding, with no high ground on which to take refuge.