China has seen frequent barrier lake breach hazards since 2000. Several cases have monitored with complete breach flood hydrographs that enabled the improvement to the existing dam breach analysis methods by merging hydraulics and soil mechanics expertise. Highlights of this paper include the improved hyperbolic soil erosion and lateral enlargement models, and a numerical algorithm that allows straightforward calculation of the breach flood hydrograph. The calculated peak flows using this improved method are in general agreement with field measurements and are less sensitive to input parameters. The research outcomes have been incorporated into the spreadsheet DB-IWHR and can be used to perform dam breach flood calculations. It is particularly useful in emergencies when a quick and easy evaluation of the breach flood is required.

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