A Numerical Study of Historical Dam Failures Using DSS-WISE Lite Web-Based System

In the context of dam safety, understanding past dam failures through numerical modeling holds significant importance. This not only helps unravel the complexities and consequences of historical incidents but also plays a crucial role in enhancing our preparedness for potential future events. This study used the Decision Support System for Water Infrastructural Security Lite (DSS-WISE™ Lite) web-based system to investigate two historical dam breach incidents: the 2005 Taum Sauk Upper Dam failure and the 2020 Edenville Dam and Sanford Dam failure. The numerical simulations were conducted using two-dimensional modeling techniques, considering distinct scenarios for each incident. For the Taum Sauk Upper Dam failure case, simulations were performed for a sunny-day scenario, focusing on the breach of only the upstream dam in a two-dam series. The results showed a high level of agreement between the simulated and observed inundation extents, with an overall F statistic value of 84.1%. In the case of the Edenville Dam and Sanford Dam failure, simulations were executed for a wet-day scenario involving cascading failures of two dams. The cascading characteristic is currently not supported by the DSS-WISE Lite web-based version due to its restriction to breaching only one structure per simulation. To address this limitation, two approaches were employed to study the 2020 Edenville Dam and Sanford Dam cascading failure case. The first approach used the DSS-WISE Lite web-based version in conjunction with a combined hydrograph technique. The second method involved using the full version of the DSS-WISE solver, which permits multiple breaches but is not publicly accessible. For this case, the results showed varying degrees of agreement between the simulated and observed extents, with certain areas demonstrating good agreement. The full version of the DSS-WISE model slightly outperformed the combined hydrograph approach in replicating observed extents.