Debris-Flow Hazard Assessment of the Area Burned by the 2013 Beaver Creek Fire
In August 2013, the Beaver Creek wildfire burned more than 100,000 acres of public and private land northwest of Hailey, Idaho. According to the U.S. Forest Service, about 57 percent of the area is considered moderately burned, and the risk of post-fire soil erosion is high on more than 8,400 acres.
In cooperation with Blaine County, we have developed a model to estimate the probability of occurrence, volume, and combined hazard ranking of debris flows in the burned area. This model uses topographic, soil, burn severity, and storm (rainfall) intensity variables to estimate the probability and volume of debris flows. The probability and volume estimates are ranked and combined to estimate a relative hazard ranking for debris flows. The models evaluate three storms scenarios:
- 2-year-recurrence, 1-hour duration rainfall of 13 millimeters (mm), referred to as a 2-year storm (a 50-percent chance of occurrence in any given year)
- 10-year-recurrence, 1-hour-duration rainfall of 19 mm, referred to as a 10-year storm (a 10-percent chance of occurrence in any given year)
- 25-year-recurrence, 1-hour-duration rainfall of 22 mm, referred to as a 25-year storm (a 4-percent chance of occurrence in any given year)
Below are partners associated with this project.
In August 2013, the Beaver Creek wildfire burned more than 100,000 acres of public and private land northwest of Hailey, Idaho. According to the U.S. Forest Service, about 57 percent of the area is considered moderately burned, and the risk of post-fire soil erosion is high on more than 8,400 acres.
In cooperation with Blaine County, we have developed a model to estimate the probability of occurrence, volume, and combined hazard ranking of debris flows in the burned area. This model uses topographic, soil, burn severity, and storm (rainfall) intensity variables to estimate the probability and volume of debris flows. The probability and volume estimates are ranked and combined to estimate a relative hazard ranking for debris flows. The models evaluate three storms scenarios:
- 2-year-recurrence, 1-hour duration rainfall of 13 millimeters (mm), referred to as a 2-year storm (a 50-percent chance of occurrence in any given year)
- 10-year-recurrence, 1-hour-duration rainfall of 19 mm, referred to as a 10-year storm (a 10-percent chance of occurrence in any given year)
- 25-year-recurrence, 1-hour-duration rainfall of 22 mm, referred to as a 25-year storm (a 4-percent chance of occurrence in any given year)
Below are partners associated with this project.