Characteristics of Extreme Storms in Montana and Methods for ConstructingSynthetic Storm Hyetographs

摘要

To allow dam-safety and design engineers to better evaluate risk of dam failureand establish a more consistent basis for spillay design, two-phase study was undertaken by the U.S. Geological Survey in Montana, in cooperation with the Dam Safety Section of the Montana Department of Natural Resources and Conservation. The objectives of the second phase of the cooperative study were to (1) analyze the temporal characteristics of large storms in Montana, and (2) develop methods for constructing probabilistic synthetic storm hyetographs that reflect temporal characteristics of observed storms in the study area. The analyses were conducted for three homogeneous regions within which precipitation characteristics were considered to be reasonable uniform and distinct.