Variable-Height Bulkhead Design Concept for Storm Flood Protection

Wave overtopping and subsequent flooding during coastal storms result in significant damages in many areas. However, balancing engineering design functionality with public and community desire to maintain beach and waterfront views are often a challenge. Here, a variable-height bulkhead design concept is introduced. This bulkhead is designed to rise and fall with floodwaters to achieve design overtopping protection while maintaining views during nonstorm conditions. In this technical note, the functional variable-height bulkhead design is presented and laboratory tested. The design requirement that the bulkhead rise and fall with water levels was validated through this testing. Experimental results indicate that the variable-height bulkhead provides overtopping protection comparable to that of a static vertical wall with the same freeboard, showing that the variable-height bulkhead concept is, in terms of overtopping, a viable alternative for coastal storm protection. Testing has been carried out mainly for low energy conditions occurring, for example, in coastal bays and harbors. Further testing is required to include higher-energy environments such as the open coast. Finally, testing the structural design of the system is of primary importance.