A method is proposed to delineate hazard maps for flooding and mud and debris flow events, based on the application of a two-dimensional flood routing model FLO-2D. The method defines hazard levels based on flood event frequency and intensity. The FLO-2D model has been enhanced with pre- and post-processor programs to automate data input and to generate hazard maps in Arc View GIS format. The proposed methodology was tested in twenty three sites in the Caracas and Vargas State region in Venezuela. This paper describes one application of the proposed method to the community of Tanaguarena on the Cerro Grande alluvial fan. The model results compare very well to the maximum flow depths and area of inundation observed during the December 1999 Vargas debris flow disaster. The hazard maps for the region are being used by local agencies to develop emergency plans and new land use policies. The methodology is being expanded to other flood hazard regions in Latin America.
