The Red River valley has seen floods since long before Fargo was established. There was a tradition among the Native Americans of the region overflowed its banks and the whole Red River Valley became a sea in the spring. The tradition has lived on to the dismay of many as the floods continue today. The reasons for the floods are several. Geological factors contribute. For example, the river flows north where ice jams may prevent runoff. The flatness of the land allows rapid spread of rising waters. Climatic factors also contribute, e.g., heavy precipitation in the early spring that combines with melting snow. More information can be found at the excellent NDSU flood web page.