Application of a Simplified Dam Failure Analysis on the Susquehanna River Valley

Elaine Langone Center, Terrace Room

A simple, conservative dam failure analysis methodology is applied to the Susquehanna River Valley. This method, the Volume Method, is a screening tool that allows a desktop study (i.e., with spreadsheets and GIS) to produce a conservative dam failure analysis, providing a low-cost alternative to detailed modeling studies for delineating dam failure flood hazards at vital structures. Detailed dam failure analysis can be very costly for large watersheds that contain numerous dams. While this level of detailed analysis is necessary for evaluating the safety of some structures, a simplified, conservative screening method could reduce engineering costs for some sites by eliminating the need for costly detailed analysis. The Volume Method compares the total volume of water storage contained in upstream dams (i.e., the volume of water impounded if all upstream reservoirs were full) to the volume of storage in the watershed upstream of a site / structure. The volume of storage in upstream dams is obtained from databases such as the National Inventory of Dams, which provides comprehensive information for most dams in the United States. The volume of storage available upstream of the site / structure is determined using topographic data for the watershed and GIS tools. A case study of this method will be presented, demonstrating the safety of an important structure.