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Velocities and sand concentrations measured along 20 transects at the Field Research Facility (FRF) at Duck, North Carolina during October 16-23, 1997 are analyzed to examine the cross-shore and longshore suspended sand transport in the FRF pier depression. The suspended sand volume [V.sub.s] per unit bottom area remains large outside the surf zone in the depression. The depth-integrated offshore and longshore suspended sand transport rates are shown to be estimated as a, [bar.U] [V.sub.s] and [bar.V] [V.sub.s], respectively, where the empirical parameter a is in the range of 0.1-0.4 in the depression, [bar.U] is the cross-shore current and [bar.V] is the longshore current. The offshore suspended sand transport rate at the end of the pier is estimated to be as large as 3.5 [m.sup.3]/h/m at the peak of a storm with an offshore significant wave height of 3.5 m. The sand transported offshore appears to have been supplied by the longshore sand transport toward the pier depression. CE Database subject headings: Littoral currents; Waves; Sand; Suspended sediment; Sediment transport; Beaches; Piers.

The prediction of berm and dune erosion during a storm is essential for storm damage assessment. Simple and transparent formulas for the cross-shore and longshore transport rates of suspended sediment and bed load on beaches are proposed and incorporated into a combined wave and current model to predict the berm and dune erosion under normally and obliquely incident irregular waves. Two small-scale experiments for two different berm profiles were conducted for the calibration of the developed numerical model. The calibrated numerical model is shown to predict the measured berm and dune erosion in these experiments as well as dune erosion measured in three large-scale tests with errors less than a factor of two. The numerical model is used to examine the effects of the wave period and incident wave angle on the berm and dune erosion. These effects are computed to be within a factor of two. DOI: 10.1061/(ASCE)0733-950X(2009)135:1(1) CE Database subject headings: Berms; Dunes; Sand; Erosion; Beaches; Sediment transport; Bed loads; Storms; Surf zone.