The Utah landslides, debris flows, and floods of May and June 1983.

Bibliography: p. 87-89

During approximately three months in the spring of 1983, the state of Utah, with a population of about 2 million people, sustained direct damages from landslides, debris flows, mud floods, and flooding in excess of $250 million. Based on hydrologic records of precipitation and on snow surveys, which indicated that snowpacks were from 150 to 400 percent of normal, Utah's public officials and citizens were prepared for above-normal stream flows and some water flooding. However, neither the scientific community nor state emergency agencies foresaw or prepared for the widespread landsliding, devastating debris (and mud) flows, and mud floods that were initiated from mountain landslides. These disastrous events were so widespread and extensive that 22 of the 29 counties in the state were declared national disaster areas