In 2005, Hurricane Katrina breached a 2 km wide channel in Dauphin Island, Alabama, forming what became known as the Katrina Cut. A rubble mound structure was built in 2011 to close the breach channel. Following the closure, significant beach recovery was observed seaward of the structure, with dry beach width increasing over 105 m between 2011 and 2023 and decreasing up to 39 m on the neighboring beach. The numerical model CSHORE and available data during 2015–2023 were used to investigate the recovery of the eroded beach seaward of the closed Katrina Cut. The computed onshore sand transport rate was sufficient for the observed beach recovery. The computed longshore sand transport rate was on the order of 105 m3/year and smaller on the recovering beach with larger water depth. During Hurricane Nate (2017), the recovering beach significantly reduced wave energy reaching the structure by decreasing depth-limited breaking wave height, thereby mitigating wave-induced damage. The temporary rubble mound structure played a dual role by initiating beach recovery and, in turn, gaining long-term structural resilience as the accreting beach progressively reduced its exposure to wave forces.