The California Department of Water Resources sought to characterize flows and inundation areas resulting from the hypothetical failure of 8 dams throughout the state. To provide this information, we developed computer models to simulate dambreak failures and determine dambreak hydrographs, and simulate the overland progression of the dambreak floodwaves. Inundation maps were developed using ArcGIS to depict graphically the computed inundation results.

Our tasks included:

  • Obtaining and reviewing prior dambreak and inundation mapping studies.
  • Identifying and collecting data for developing the dambreak and inundation models.
  • Preparing, building, and running dambreak models following Federal Energy Regulatory Commission (FERC) guidelines to compute dambreak hydrographs.
  • Developing dambreak inundation models (FLO-2D and/or HEC-RAS models).
  • Executing the dambreak inundation models with the dam failure hydrographs.
  • Constructing maps using ArcGIS and graphs and tables to present inundation modeling results.
  • Preparing technical memoranda describing the dambreak analysis alternatives and justification for the selected alternative for this study, failure analysis assumptions, model inputs, and results.
  • Conducting a technology transfer workshop.
  • Developing a final study report for each dam.

The results of these efforts will be used to evaluate the effects on downstream critical infrastructure. The inundation maps will help emergency managers develop emergency response plans to address potential dam failures.