A real-time debris prediction model (USCDPM) incorporating wildfire and subsequent storm events

Alluvial fans are continuously being developed for residential, industrial, commercial, and agricultural purposes in southern California. Development of these areas must consider the generation of mud and debris flows from burned mountain watersheds. Accurate prediction of debris yield is essential for the design, operation, and maintenance of debris basins. This study develops a model for the prediction of debris yield resulting from a combination of wildfire and subsequent storm events.; The watersheds used in this analysis are located in the San Gabriel Mountains. A multiple regression analysis is first utilized to establish a fundamental mathematical relationship using 46 years of data (1938--1983). Following the multiple regression analysis, a method (USCDPM) for debris yield prediction is developed and calibrated based on 17 years of debris yield, fire, and precipitation data (1984--2000).; A debris routing method is developed to predict the temporal and spatial variations of a debris flow as it moves through watershed channel reaches for the large watershed. The William Fire (September 22, 2002) in the Azusa to Claremont area is used to calibrate the routing method of USCDPM applied to large watersheds. After calibration with debris routing method, this model is applied to provide real-time prediction of the debris yields from the 2001--2003 fire events based on the Radio Telemetry Gage information.; The model results have been found to agree well with the field data. The proposed method for debris yield prediction can be a useful tool for watershed management in the arid Southwest region.