Overwash induced by storms is one of the factors that threaten coastlines, causing erosion and sediment transport, especially in areas of low dune elevation. Laboratory experiments provide mechanisms for eliminating many of the varied environmental conditions that typically exist in the field. For instance, it is difficult to observe conditions before and after the landfall of a storm; however, such observations are much simpler in a laboratory setting. The experiments conducted in this study focused on the volume of eroded and transported sediment by overwash of the berm and dune at different slopes, the wave heights, and the periods of regular and irregular waves. Experiments were conducted under both short-term (327 s) and longer-term conditions (30, 60, and 180 min). The newly developed zero-point method that calculates the offshore and onshore sediment transport was used for analysis and was verified with field measurements. The empirical equations were developed using robust regression after selecting dominant factors in a sensitivity analysis. The regression equations compared favorably with the laboratory and field data. The empirical equation for irregular waves proved to be a simple and quick way to estimate the landward sediment transport rate by overwash.