CASTOR: Simplified Dam-Break Wave Model

Abstract

The five computation steps of CASTOR—a simplified dam-break, flood-wave model—are described. The first step uses a simple relation to determine peak discharge at the dam. Second, a dimensionless graph gives peak discharge at the distance x from the dam. Afterwards the uniform-flow equation is used to compute peak water elevation, peak velocity, and wave arrival time. The validation of these last three steps is obtained on a set of 15 dams and 440 channel cross sections by comparison to the results of the model RUBAR 3, which solves Saint Venant equations. The deviation is less than 30% for peak water depth and 50% for other results in more than 90% of the cross sections. Such statistically justified results might be used independently from CASTOR. The example of the Lawn Lake Dam failure is treated by CASTOR; except for a point where the topography changed during the flood, peak water depth shows a deviation less than 20%.